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University of Massachusetts Amherst

2019

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Phrasal And Clausal Exceptive-Additive Constructions Crosslinguistically, Ekaterina Vostrikova Oct 2019

Phrasal And Clausal Exceptive-Additive Constructions Crosslinguistically, Ekaterina Vostrikova

Doctoral Dissertations

This work focuses on the syntax and semantics of exceptive and exceptive-additive constructions across different languages. Exceptive-additive constructions are constructions that can be interpreted as ‘except for’ and ‘in addition to’ depending on the context they are used in. The meaning an exceptive-additive construction gets depends on the other functional elements in a sentence. Those constructions get the exceptive meaning when they are put together with universal quantifiers and they get the additive meaning with existentials, wh-words and focus associates. In each context only one of the meanings is available. This work is the first systematic study of the …

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Extracting And Representing Entities, Types, And Relations, Patrick Verga Oct 2019

Extracting And Representing Entities, Types, And Relations, Patrick Verga

Doctoral Dissertations

Making complex decisions in areas like science, government policy, finance, and clinical treatments all require integrating and reasoning over disparate data sources. While some decisions can be made from a single source of information, others require considering multiple pieces of evidence and how they relate to one another. Knowledge graphs (KGs) provide a natural approach for addressing this type of problem: they can serve as long-term stores of abstracted knowledge organized around concepts and their relationships, and can be populated from heterogeneous sources including databases and text. KGs can facilitate higher level reasoning, influence the interpretation of new data, and …

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Residual Stress Models For Large Eddy Simulation Of Stratified Turbulent Flows, Felipe Augusto Ventura De Bragança Alves Oct 2019

Residual Stress Models For Large Eddy Simulation Of Stratified Turbulent Flows, Felipe Augusto Ventura De Bragança Alves

Doctoral Dissertations

The residual stresses and scalar fluxes are required to close the momentum and scalar transport equations in simulations of turbulence that are not fully resolved in space. In stratified turbulence, the stress and fluxes are statistically anisotropic unless the smallest resolved length scale is smaller than the Ozmidov scale and the buoyancy Reynolds number is sufficiently high for there to exist a range of scales that is statistically isotropic. In this work, a tensorial basis set is derived analytically that potentially contains sufficient information about the anisotropic interaction between resolved and residual scales. The residual stress tensor is evaluated by …

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Service Competition And Data-Centric Protocols For Internet Access, Thiago Teixeira Oct 2019

Service Competition And Data-Centric Protocols For Internet Access, Thiago Teixeira

Doctoral Dissertations

The Internet evolved in many aspects, from the application to the physical layers. However, the evolution of the Internet access technologies, most visible in dense urban scenarios, is not easily noticeable in sparsely populated and rural areas. In the United States, for example, the FCC identified that 50% of the census blocks have access to up to two broadband providers; however, these providers do not necessarily compete. Additionally, due to the methodology of the study, there is evidence that the number of actual customers without broadband access is higher since the FCC considers the entire block to have broadband if …

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Efficient Self-Supervised Deep Sensorimotor Learning In Robotics, Takeshi Takahashi Oct 2019

Efficient Self-Supervised Deep Sensorimotor Learning In Robotics, Takeshi Takahashi

Doctoral Dissertations

Deep learning has been successful in a variety of applications, such as object recognition, video games, and machine translation. Deep neural networks can automatically learn important features given large training datasets. However, the success of deep learning in robotic systems in the real world is still limited mainly because obtaining large datasets and labeling are costly. As a result, much of the successful work in deep learning has been limited to domains where large datasets are readily available or easily collected. To address this issue, I propose a framework for acquiring re-usable skills efficiently combining intrinsic motivation and the control …

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Understanding China’S Discourse On South-South Cooperation And China-Africa Higher Education Exchange: A Field Research Study At Zhejiang Normal University’S China-Africa International Business School, Yi Sun Oct 2019

Understanding China’S Discourse On South-South Cooperation And China-Africa Higher Education Exchange: A Field Research Study At Zhejiang Normal University’S China-Africa International Business School, Yi Sun

Doctoral Dissertations

This dissertation research attempts to distinguish China’s model from that of the traditional North-South relationship, with a focus on how China’s philosophy articulates its foreign policy and the nation’s higher education engagement with African countries. It examines the China-Africa higher education partnership in response to China’s discourse on South-South Cooperation (SSC), Africa’s human resource flows, and the benefits and constraints of current China-Africa cooperation. In order to achieve these goals, the dissertation uses one of the China-Africa partnership universities in China, Zhejiang Normal University (ZJNU) as a site for its field research. The fieldwork looks at both a student level …

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Machine Learning Models For Efficient And Robust Natural Language Processing, Emma Strubell Oct 2019

Machine Learning Models For Efficient And Robust Natural Language Processing, Emma Strubell

Doctoral Dissertations

Natural language processing (NLP) has come of age. For example, semantic role labeling (SRL), which automatically annotates sentences with a labeled graph representing who did what to whom, has in the past ten years seen nearly 40% reduction in error, bringing it to useful accuracy. As a result, a myriad of practitioners now want to deploy NLP systems on billions of documents across many domains. However, state-of-the-art NLP systems are typically not optimized for cross-domain robustness nor computational efficiency. In this dissertation I develop machine learning methods to facilitate fast and robust inference across many common NLP tasks. First, …

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Metabolic Cost Of Asymmetrical Walking: Preferred Step Time Asymmetry Optimizes Metabolic Cost Of Walking, Jan Stenum Oct 2019

Metabolic Cost Of Asymmetrical Walking: Preferred Step Time Asymmetry Optimizes Metabolic Cost Of Walking, Jan Stenum

Doctoral Dissertations

Hemiparetic and amputee walking often has asymmetrical step lengths and step times, and it is metabolically costlier than symmetrical able-bodied walking. Consequently, asymmetry has been suggested to account for the greater energy expenditure, but the metabolic cost of asymmetrical walking is poorly understood. Conversely, even though symmetry is metabolically optimal in able-bodied walking, it is also possible that asymmetrical gait parameters may be selected if they are optimal under imposed constraints. First, to understand the metabolic cost of asymmetry, we performed experiment 1 in which we recruited 10 able-bodied subjects to walk with a range of different combinations of asymmetrical …

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The Solution Is The Problem: An Immanent Critique Of Capitalism's Crisis, 2008-2018, Michael Stein Oct 2019

The Solution Is The Problem: An Immanent Critique Of Capitalism's Crisis, 2008-2018, Michael Stein

Doctoral Dissertations

This dissertation examines the way that capitalism responded to the financial crisis of 2008 by presenting itself as the solution to problems of its own making. Guiding my criticism, is the concept of immanent critique and these chapters represent works of critical theory that endeavor to think through the contradictions of contemporary capitalism. The chapters of this dissertation examine capitalism’s response to it’s own crisis in four domains: political consumerism, the 2010 Haitian earthquake, philanthropy, and the prosperity gospel. Each of these responses seeks to overcome one or more of the fundamental problems of capitalism – inequality, poverty, environmental degradation, …

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“You Can Be A Good Romanian, But Not A Romanian”: A Critical Discourse Analysis Of The Romanian History Textbook Narrative, Razvan Sibii Oct 2019

“You Can Be A Good Romanian, But Not A Romanian”: A Critical Discourse Analysis Of The Romanian History Textbook Narrative, Razvan Sibii

Doctoral Dissertations

Employing a version of the Critical Discourse Analysis methodology that privileges close textual readings, I examine in this dissertation the manner in which contemporary Romanian history textbooks put forward an essentialist view of ethnonational identity by tracing through history the development of a putatively homogenous “proto-Romanian” entity. I seek to show how the “Getae-Dacian” and “Daco-Roman” identity categories acquired their thing-ness and their boundaries as a result of deliberate rhetorical work performed by Romanian historiographers with the help of such heuristics as “Romanization,” “ethnogenesis” and the nation-as-family metaphor. I also scrutinize how the textbooks treat the two ancient texts that …

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The Influence Of Wind Power On Rural Areas Economic, Demographic, And Community Services Impacts, Eman Shoeib Oct 2019

The Influence Of Wind Power On Rural Areas Economic, Demographic, And Community Services Impacts, Eman Shoeib

Doctoral Dissertations

Wind power development has rapidly expanded in the United States. Much of this growth occurred in rural areas because of the availability of land and wind resources required to power turbines. The economic promise of wind power projects is particularly appealing for rural areas whose traditional economic base (typically agricultural) no longer supports as many households as it once did. Numerous studies have found that wind power projects have positive economic impacts on rural areas. What is less well understood is the effect of these wind power farms on other indicators of development, such as municipal services, demographic change, and …

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Emotional Response To Negative Mood Induction In Mild Cognitive Impairment And Cognitively-Intact Older Adults, Gennarina Diane Santorelli Oct 2019

Emotional Response To Negative Mood Induction In Mild Cognitive Impairment And Cognitively-Intact Older Adults, Gennarina Diane Santorelli

Doctoral Dissertations

Older adults with mild cognitive impairment (MCI) report greater rates of psychiatric symptoms than cognitively-intact older persons. This may be associated with emotion dysregulation, which is prevalent in cognitively-impaired populations. No research to date has investigated responses to emotionally-provocative stimuli in persons with MCI. Aim 1 of this study determined differences in emotional reactivity to and recovery from negative mood induction in older persons with amnestic MCI (aMCI) and cognitively-healthy older adults. Moreover, emotion dysfunction in MCI may be linked to impairment in executive function (EF), a common feature of MCI. Theoretical models postulate that EF is essential to the …

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Protein Detection And Structural Characterization By Mass Spectrometry Using Supramolecular Assemblies And Small Molecules, Bo Zhao Oct 2019

Protein Detection And Structural Characterization By Mass Spectrometry Using Supramolecular Assemblies And Small Molecules, Bo Zhao

Doctoral Dissertations

Mass spectrometry (MS) has played an increasingly prominent role in proteomics and structure biology because it shows superior capabilities in identification, quantification and structural characterization of proteins. To realize its full potential in protein analysis, significant progress has been made in developing innovative techniques and reagents that can couple to MS detection. This dissertation demonstrates the use of polymeric supramolecular assemblies for enhanced protein detection in complex biological mixtures by MS. An amphiphilic random co-polymer scaffold is developed to form functional supramolecular assemblies for protein/ peptide enrichment. The influences of charge density and functional group pKa on host-guest interactions …

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Environmental Risk Factors For Inflammatory Bowel Disease: Triclosan And Other Consumer Antimicrobials, Katherine Z. Sanidad Oct 2019

Environmental Risk Factors For Inflammatory Bowel Disease: Triclosan And Other Consumer Antimicrobials, Katherine Z. Sanidad

Doctoral Dissertations

Inflammatory bowel disease (IBD) has become a serious health problem since the incidence and prevalence of IBD has dramatically increased throughout the world. There is evidence that environmental factors are primarily responsible for the increase of IBD, therefore, it is important to identify novel environmental risk factors to reduce the risk of IBD and its associated diseases. Antimicrobials used in consumer products might serve as environmental risk factors for IBD and its associated diseases. Triclosan (TCS), triclocarban (TCC), benzalkonium chloride (BAC), benzethonium chloride (BET), and chloroxylenol (PCMX) are widely used antimicrobial ingredients in consumer products and are ubiquitous contaminants in …

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Factors Influencing Spartina Alterniflora Productivity In Relationship To Estuary Inlet Opening Ellisville Marsh, Plymouth, Ma, Ellen K. Russell Oct 2019

Factors Influencing Spartina Alterniflora Productivity In Relationship To Estuary Inlet Opening Ellisville Marsh, Plymouth, Ma, Ellen K. Russell

Doctoral Dissertations

A scientific basis for understanding the health of salt marsh vegetation, primarily Spartina alterniflora, in apposition to dredging of the tidal inlet to Ellisville Marsh in Plymouth, Massachusetts was determined. A three-hectare S. alterniflora loss, and coincident coastal bank erosion occurred; ostensibly due to inlet blockage from sand deposition, prolonged inundation, and meandering of inlet channel into coastal bank. This warranted dredging the tidal inlet, whereby tidal flushing would restore growth or discontinue die-off, and deter coastal bank erosion. A pre- and post dredge study was conducted assessing environmental factors related to plant productivity. Following dredging, an increase in …

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Changes In Soil Microbial Communities After Long-Term Warming Exposure, William G. Rodríguez-Reillo Oct 2019

Changes In Soil Microbial Communities After Long-Term Warming Exposure, William G. Rodríguez-Reillo

Doctoral Dissertations

Microbial metabolism is a key controller of ecosystem processes (e.g., carbon cycling). However, we are only starting to identify the molecular mechanisms and feedback in response to long-term warming. My dissertation integrates multi-omics techniques to capture changes in soil microbial communities after long-term warming exposure. The research projects leverage three warming sites (i.e., SWaN, Barre Woods, and Prospect Hill) located in Western Massachusetts at Harvard Forest. These sites provided a unique experimental setup to better understand microbes in response to long-term temperature change. For the three research projects, we delved into the (i) microbial biodiversity across all three warming sites, …

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Three Essays On Firm Behaviors In Online Market Platforms, Erfan Rezvani Oct 2019

Three Essays On Firm Behaviors In Online Market Platforms, Erfan Rezvani

Doctoral Dissertations

Across many online market platforms, customer reviews have become a prevailing mechanism to evaluate firms and disseminate information about the quality of their products/services. While prior research has well-documented the impact of such customer-generated information on firm performance such as sales (e.g. Chevalier & Mayzlin 2006, Liu, 2006), understanding how firms react to customer evaluations generates an interesting yet an underexplored topic for research. This dissertation, through three studies, aims to investigate how customer reviews tat are posted on online platforms shape how firms learn, communicate, and compete. Chapter 1 shows that learning from own experience follows an inverted U-shaped …

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Top-Down And Bottom-Up Fabrication Of Key Components In Miniature Energy Storage Devices, Wenhao Li Oct 2019

Top-Down And Bottom-Up Fabrication Of Key Components In Miniature Energy Storage Devices, Wenhao Li

Doctoral Dissertations

The advent of miniature electronic devices demands power sources of commensurate form factors. This spurs the research of micro energy storage devices, e.g., 3D microbatteries. A 3D microbattery contains nonplanar microelectrodes with high aspect ratio and high surface area, separated by a nanoscale electrolyte. The device takes up a total volume as small as 10 mm3, allowing it to serve on a chip and to provide power in-situ. The marriage of nanotechnology and electrochemical energy storage makes microbattery research a fascinating field with both scientific excitement and application prospect. However, successful fabrication of well-functioned key components …

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Characterization Of The Anomalous Ph Of Aqueous Nanoemulsions, Kieran P. Ramos Oct 2019

Characterization Of The Anomalous Ph Of Aqueous Nanoemulsions, Kieran P. Ramos

Doctoral Dissertations

Aqueous water-in-oil nanoemulsions have emerged as a versatile tool for use in microfluidics, drug delivery, single-molecule measurements, and other research. Nanoemulsions are often prepared with perfluorocarbons which are remarkably biocompatbile due to their stability, low surface tension, lipophobicity, and hydrophobicity. Therefore it is often assumed that droplet contents are unperturbed by the perfluorinated surface. However, in microemulsions, which are similar to nanoemulsions, it is known that either the pH of the aqueous phase or the ionization constants of encapsulated molecules are different from bulk solution. There is also recent evidence of low pH in perfluorinated aqueous nanoemulsions. The current underlying …

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Silver Mirror Substrate And Rolling Method For Improved Surface-Enhanced Raman Spesctroscopic Analysis In Food, Yanqi Qu Oct 2019

Silver Mirror Substrate And Rolling Method For Improved Surface-Enhanced Raman Spesctroscopic Analysis In Food, Yanqi Qu

Doctoral Dissertations

Surface-enhanced Raman spectroscopy, short for SERS, is an emerging technology with great potential in food analysis due to rapid detection, high sensitivity, portable instrumentation, and simple sample preparation. However, it is always a bottleneck to obtain reproducible SERS measurements in real analytical cases due to the complicity of food systems and inhomogeneous aggregation of colloidal nanoparticles. To improve its performance for practical applications in food analysis, efforts have been made in improving the reproducibility, enhancing the selectivity and reducing the matrix interference to the analyte. Herein, a self-assembly silver nanoparticles mirror substrate was fabricated to improve the and the quantitative …

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Time-Difference Circuits: Methodology, Design, And Digital Realization, Shuo Li Oct 2019

Time-Difference Circuits: Methodology, Design, And Digital Realization, Shuo Li

Doctoral Dissertations

This thesis presents innovations for a special class of circuits called Time Difference (TD) circuits. We introduce a signal processing methodology with TD signals that alters the target signal from a magnitude perspective to time interval between two time events and systematically organizes the primary TD functions abstracted from existing TD circuits and systems. The TD circuits draw attention from a broad range of application fields. In addition, highly evolved complementary metal-oxide-semiconductor (CMOS) technology suffers from various problems related to voltage and current amplitude signal processing methods. Compared to traditional analog and digital circuits, TD circuits bring several compelling features: …

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Effects Of Ivermectin And Perfluorobutanesulfonic Acid (Pfbs) On Lipid Metabolism, Weipeng Qi Oct 2019

Effects Of Ivermectin And Perfluorobutanesulfonic Acid (Pfbs) On Lipid Metabolism, Weipeng Qi

Doctoral Dissertations

Accumulating evidence has shown a link between environmental contaminants and altered lipid metabolism. There is currently, however, limited knowledge regarding the causal molecular mechanisms. Therefore, we investigated the molecular mechanisms of two environmental contaminants, ivermectin and perfluorobutanesulfonic acid (PFBS), on lipid metabolism in adipocytes and hepatocytes using cell culture models. We first studied the effects of ivermectin, an anti-parasitic agent, on the adipogenesis of 3T3-L1 preadipocytes. Our current results suggest that ivermectin inhibits adipogenesis in 3T3-L1 preadipocytes and the expression of adipogenic genes where these effects were found to be partially via PPARγ-dependent, but not FXR-dependent, pathway. Additionally, ivermectin also …

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The Social Process Of Dying In The Hospital: A Grounded Theory Study, Alyson Prokop Oct 2019

The Social Process Of Dying In The Hospital: A Grounded Theory Study, Alyson Prokop

Doctoral Dissertations

The majority of deaths in the United States occur in the hospital (Xu, Kochanek, Murphy, & Tejada-Vera, 2010). Because there is little understanding of the meaning behind this delicate social process for the patient, the purpose of this study was to develop a theory that describes the social processes one undergoes during the in-hospital end-of-life phase. Grounded theory methodology was chosen to understand this phenomenon and then explain it theoretically (Charmaz, 1990). The data used to develop the theoretical model was previously collected by StoryCorps and therefore components of secondary analysis were taken into consideration. Stories that are housed at …

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Software-Defined Infrastructure For Iot-Based Energy Systems, Stephen Lee Oct 2019

Software-Defined Infrastructure For Iot-Based Energy Systems, Stephen Lee

Doctoral Dissertations

Internet of Things (IoT) devices are becoming an essential part of our everyday lives. These physical devices are connected to the internet and can measure or control the environment around us. Further, IoT devices are increasingly being used to monitor buildings, farms, health, and transportation. As these connected devices become more pervasive, these devices will generate vast amounts of data that can be used to gain insights and build intelligence into the system. At the same time, large-scale deployment of these devices will raise new challenges in efficiently managing and controlling them. In this thesis, I argue that the IoT …

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Controlling Selectivities In Heterogeneously Catalyzed Aldol Reactions, Koushik Ponnuru Oct 2019

Controlling Selectivities In Heterogeneously Catalyzed Aldol Reactions, Koushik Ponnuru

Doctoral Dissertations

Aldol condensation is an important C-C bond formation reaction in chemical synthesis that finds versatile applications in bulk and fine chemical industries and has the potential for upgrading of biomass to fuels. However, aldol reactions pose a challenge for controlling the product selectivity by forming a mixture of desired and undesired self, cross, and poly-condensation products. Furthermore, a side reaction, the fission of aldol products resulting in an olefin and a carboxylic acid, has garnered attention recently as a route to isobutene from acetone. While a high level of selectivity control is achievable by homogeneous catalysis, selective solid catalysts, which …

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Bioinspired Complex Nanoarchitectures By Dna Supramolecular Polymerization, Laura A. Lanier Oct 2019

Bioinspired Complex Nanoarchitectures By Dna Supramolecular Polymerization, Laura A. Lanier

Doctoral Dissertations

Bioinspired nanoarchitectures are of great interest for applications in fields such as nanomedicine, tissue engineering, and biosensing. With this interest, understanding how the physical properties of these complex nanostructures relate to their function is increasingly important. This dissertation describes the creation of complex nanoarchitectures with controlled structure and the investigation of the effect of nanocarrier physical properties on cell uptake for applications in nanomedicine. DNA self-assembly by supramolecular polymerization was chosen to create complex nanostructures of controlled architectures. We demonstrated that the supramolecular polymerization of DNA known as hybridization chain reaction (HCR) is in fact a living polymerization. The living …

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Drivers And Consequences Of Carbon Use Efficiency - And Its Measurement In Soil, Grace Pold Oct 2019

Drivers And Consequences Of Carbon Use Efficiency - And Its Measurement In Soil, Grace Pold

Doctoral Dissertations

Soils serve as massive carbon sinks, but their ability to continue this ecological service is contingent on how the resident soil microbial community will respond to the ongoing climate crisis. One key dimension of the microbial response to warming is its carbon use efficiency (CUE), or the fraction of carbon taken up by an organism which is allocated to growth rather than respiration. However, the scientific community is still in the early stages of understanding the drivers, consequences - and even accurate measurements of - CUE. In this dissertation, I first quantified the variability of CUE and its responsiveness to …

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Providing Molecular Insight For Understanding Anion Exchange Membrane Conductivity, Michael Kwasny Oct 2019

Providing Molecular Insight For Understanding Anion Exchange Membrane Conductivity, Michael Kwasny

Doctoral Dissertations

Anion exchange membranes (AEMs) are notorious for having both low alkaline stability and poor ion conductivity in fuel cell operation conditions, with solutions to these two challenges often being developed independent of each other. The chemical instability of an AEM is viewed through degradation of the polymer backbone and the cationic species and improving a material’s stability is approached by altering the polymer backbone, the cation, or both. On the other hand, poor ion conductivity is typically addressed by modifying bulk membrane properties such as increasing the ion exchange capacity (IEC), changing the morphology, or increasing the water uptake. These …

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Observational Studies Of Fragmentation In Molecular Clouds, Riwaj Pokhrel Oct 2019

Observational Studies Of Fragmentation In Molecular Clouds, Riwaj Pokhrel

Doctoral Dissertations

In this dissertation, I explore fragmentation physics in multiple scales in nearby molecular clouds and discuss some implications of fragmentation for cloud structure formation and star formation, primarily by analyzing multi-wavelength observations of dust emission. First, I tested the complete thermal and combined thermal and nonthermal support mechanisms that balance gravitational contraction at multiple scales in the Perseus molecular cloud. I found that the observed multiscale structures in Perseus are consistent with an inefficient thermal Jeans fragmentation, where the Jeans efficiency increases from the largest scale ($\gtrsim$10s of pc) to the smallest scale ($\sim$10s of AU). Next, I studied the …

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Energy-Aware Algorithms For Greening Internet-Scale Distributed Systems Using Renewables, Vani Gupta Oct 2019

Energy-Aware Algorithms For Greening Internet-Scale Distributed Systems Using Renewables, Vani Gupta

Doctoral Dissertations

Internet-scale Distributed Systems (IDSs) are large distributed systems that are comprised of hundreds of thousands of servers located in hundreds of data centers around the world. A canonical example of an IDS is a content delivery network (CDN) that delivers content to users from a large global deployment of servers around the world. IDSs consume large amounts of energy and their energy requirements are projected to increase significantly in the future. With carbon emissions from data centers increasing every year, use of renewables to power data centers is critical for the sustainability of data centers and for the environment. In …

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