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Full-Text Articles in Physical Sciences and Mathematics

Seeing Through The Ottawan Overprint, Adirondack Mtns., Ny: Integrating Microstructural Analysis, Geothermobarometry, And In-Situ Monazite Petrochronology, Justin Mistikawy Apr 2020

Seeing Through The Ottawan Overprint, Adirondack Mtns., Ny: Integrating Microstructural Analysis, Geothermobarometry, And In-Situ Monazite Petrochronology, Justin Mistikawy

Masters Theses

Integrating field observation with petrochronology is critical for understanding the tectonometamorphic evolution of the North American Grenville Province. Despite methodological advances in geothermobarometry and geochronology, incorporating these data into larger models of the Adirondack Mountains remains particularly challenging due to the presence of multiple generations of deformation, primarily related to the ca. 1190 – 1140 Ma Shawinigan and ca. 1090 – 1020 Ma Ottawan Orogenies (McLelland et al.,2013). The Rock and Bear Ponds area is a dome of tight-to-isoclinally folded metapelites in structural contact with orthogneiss. Fold generations are orthogonal and partitioned such that the northern area is dominated by an ...


Threshold Processes And Stream Temperature Distribution In A Small New England Headwater Stream Catchment., Mitchell Isaacson Apr 2020

Threshold Processes And Stream Temperature Distribution In A Small New England Headwater Stream Catchment., Mitchell Isaacson

Masters Theses

Rising air temperature and decreasing stream flow trends are predicted to result in corresponding increases in stream temperatures. As a result, the future of ectothermic stream fishes, which rely on seasonal and spatial distributions of stream temperature for growth and survival, could be in jeopardy. Fortunately, contradicting stream temperature trends in forested headwater catchments suggest that non-climatic variables, such as baseflow indices and catchment geologic structure, may have an important confounding influence on the future of stream temperature. Most significantly, the annual stability of groundwater temperature has long been recognized as an important buffer between air and stream temperature. The ...


Characterization Of Biodistribution Of Transferrin And Receptor Binding Mechanism By Mass Spectrometry, Hanwei Zhao Mar 2020

Characterization Of Biodistribution Of Transferrin And Receptor Binding Mechanism By Mass Spectrometry, Hanwei Zhao

Doctoral Dissertations

Protein-based therapeutics have emerged as a key driver of rapid growth in drug development pipelines. However, developing such protein drugs is not straightforward in most cases, the existence of physiological barriers greatly restricts the efficient delivery of many therapeutic molecules, and therefore limits their clinical applications. A promising way to address this challenge takes advantage of certain transport protein which can effectively across and enhance the permeability of these barriers, such as transferrin (Tf) which can be internalized by malignant cells and cross physiological barriers via transferrin receptor (TfR)-mediated endocytosis and transcytosis. However, developing such products is impossible without ...


Compactifications Of Cluster Varieties Associated To Root Systems, Feifei Xie Mar 2020

Compactifications Of Cluster Varieties Associated To Root Systems, Feifei Xie

Doctoral Dissertations

In this thesis we identify certain cluster varieties with the complement of a union of closures of hypertori in a toric variety. We prove the existence of a compactification $Z$ of the Fock--Goncharov $\mathcal{X}$-cluster variety for a root system $\Phi$ satisfying some conditions, and study the geometric properties of $Z$. We give a relation of the cluster variety to the toric variety for the fan of Weyl chambers and use a modular interpretation of $X(A_n)$ to give another compactification of the $\mathcal{X}$-cluster variety for the root system $A_n$.


Probabilistic Inference With Generating Functions For Population Dynamics Of Unmarked Individuals, Kevin Winner Mar 2020

Probabilistic Inference With Generating Functions For Population Dynamics Of Unmarked Individuals, Kevin Winner

Doctoral Dissertations

Modeling the interactions of different population dynamics (e.g. reproduction, migration) within a population is a challenging problem that underlies numerous ecological research questions. Powerful, interpretable models for population dynamics are key to developing intervention tactics, allocating limited conservation resources, and predicting the impact of uncertain environmental forces on a population. Fortunately, probabilistic graphical models provide a robust mechanistic framework for these kinds of problems. However, in the relatively common case where individuals in the population are unmarked (i.e. indistinguishable from one another), models of the population dynamics naturally contain a deceptively challenging statistical feature: discrete latent variables with ...


Dynamic Composition Of Functions For Modular Learning, Clemens Gb Rosenbaum Mar 2020

Dynamic Composition Of Functions For Modular Learning, Clemens Gb Rosenbaum

Doctoral Dissertations

Compositionality is useful to reduce the complexity of machine learning models and increase their generalization capabilities, because new problems can be linked to the composition of existing solutions. Recent work has shown that compositional approaches can offer substantial benefits over a wide variety of tasks, from multi-task learning over visual question-answering to natural language inference, among others. A key variant is functional compositionality, where a meta-learner composes different (trainable) functions into complex machine learning models. In this thesis, I generalize existing approaches to functional compositionality under the umbrella of the routing paradigm, where trainable arbitrary functions are 'stacked' to form ...


Search For Displaced Hadronic Vertices In The Atlas Inner Detector And Muon Spectrometer In P-P Collisions At √S = 13 Tev At The Lhc, Margaret S. Lutz Mar 2020

Search For Displaced Hadronic Vertices In The Atlas Inner Detector And Muon Spectrometer In P-P Collisions At √S = 13 Tev At The Lhc, Margaret S. Lutz

Doctoral Dissertations

A search is performed for long-lived neutral particles using 33 fb−1 of 13 TeV proton-proton collision data produced by the LHC and collected by the ATLAS detector during 2016. This search focuses on the topology in which pairs of displaced hadronic jets are produced, with one in the inner detector and the other in the muon spectrometer. Special techniques are used to reconstruct the displaced decays. One event is found passing the full signal selection, which is consistent with the back- ground estimation. Limits are set at a 95% upper confidence level on the BR × σ for a SM ...


Nanoindentation Characterization Of Elastic Properties Of Shales And Swelling Clay Minerals, Shengmin Luo Mar 2020

Nanoindentation Characterization Of Elastic Properties Of Shales And Swelling Clay Minerals, Shengmin Luo

Doctoral Dissertations

Oil and gas shales are a class of multiscale, multiphase, hybrid inorganic-organic sedimentary rocks that consist of a generally uniform, preferentially oriented clay matrix with randomly embedded silt and sand particles as solid inclusions. A thorough understanding of the mechanical properties of shales is crucial for the exploration and production of oil and gas in the unconventional shale reservoirs, but it can be a challenging task due to their nature of compositional heterogeneity and microstructural anisotropy. In efforts to better characterize the mechanical properties of shales across different length scales and to fundamentally understand the laws of upscaling from individual ...


Higher-Order Representations For Visual Recognition, Tsung-Yu Lin Mar 2020

Higher-Order Representations For Visual Recognition, Tsung-Yu Lin

Doctoral Dissertations

In this thesis, we present a simple and effective architecture called Bilinear Convolutional Neural Networks (B-CNNs). These networks represent an image as a pooled outer product of features derived from two CNNs and capture localized feature interactions in a translationally invariant manner. B-CNNs generalize classical orderless texture-based image models such as bag-of-visual-words and Fisher vector representations. However, unlike prior work, they can be trained in an end-to-end manner. In the experiments, we demonstrate that these representations generalize well to novel domains by fine-tuning and achieve excellent results on fine-grained, texture and scene recognition tasks. The visualization of fine-tuned convolutional filters ...


Learning Latent Characteristics Of Data And Models Using Item Response Theory, John P. Lalor Mar 2020

Learning Latent Characteristics Of Data And Models Using Item Response Theory, John P. Lalor

Doctoral Dissertations

A supervised machine learning model is trained with a large set of labeled training data, and evaluated on a smaller but still large set of test data. Especially with deep neural networks (DNNs), the complexity of the model requires that an extremely large data set is collected to prevent overfitting. It is often the case that these models do not take into account specific attributes of the training set examples, but instead treat each equally in the process of model training. This is due to the fact that it is difficult to model latent traits of individual examples at the ...


Improving Face Clustering In Videos, Souyoung Jin Mar 2020

Improving Face Clustering In Videos, Souyoung Jin

Doctoral Dissertations

Human faces represent not only a challenging recognition problem for computer vision, but are also an important source of information about identity, intent, and state of mind. These properties make the analysis of faces important not just as algorithmic challenges, but as a gateway to developing computer vision methods that can better follow the intent and goals of human beings. In this thesis, we are interested in face clustering in videos. Given a raw video, with no caption or annotation, we want to group all detected faces by their identity. We address three problems in the area of face clustering ...


Optimization And Training Of Generational Garbage Collectors, Nicholas Jacek Mar 2020

Optimization And Training Of Generational Garbage Collectors, Nicholas Jacek

Doctoral Dissertations

Garbage collectors are nearly ubiquitous in modern programming languages, and we want to minimize the cost they impose in terms of time and space. Generally, a collector waits until its space is full and then performs a collection to reclaim needed memory. However, this is not the only option; a collection could be performed early when some free space remains. For copying collectors, which are what we consider here, the system must traverse the graph of live objects and copy them, so the cost of a collection is proportional to the volume of objects that are live. Since this value ...


Modulating Nanoparticle-Protein Interactions Through Covalent Or Noncovalent Approach For Biomedical Applications, Jingjing Gao Mar 2020

Modulating Nanoparticle-Protein Interactions Through Covalent Or Noncovalent Approach For Biomedical Applications, Jingjing Gao

Doctoral Dissertations

Discoveries at the interface of chemistry, biology, and materials science have emerged as a powerful route to impact life science in this century. My research in the Thayumanavan group is focused on problems at this interface. A common theme of all the six projects is the use of modern synthetic organic chemistry to build interesting, novel macromolecules which are chemically rich, to study the molecular self-assembly behavior in solution and then translate to solve problems in the biomedical area. By addressing the design challenge to prepare novel amphiphiles with desired functional groups, controlled molecular weight and the ability to respond ...


An Empirical Assessment Of The Effectiveness Of Deception For Cyber Defense, Kimberly J. Ferguson-Walter Mar 2020

An Empirical Assessment Of The Effectiveness Of Deception For Cyber Defense, Kimberly J. Ferguson-Walter

Doctoral Dissertations

The threat of cyber attacks is a growing concern across the world, leading to an increasing need for sophisticated cyber defense techniques. The Tularosa Study, was designed and conducted to understand how defensive deception, both cyber and psychological, affects cyber attackers Ferguson-Walter et al. [2019c]. More specifically, for this empirical study, cyber deception refers to a decoy system and psychological deception refers to false information of the presence of defensive deception techniques on the network. Over 130 red teamers participated in a network penetration test over two days in which we controlled both the presence of and explicit mention of ...


Molecular Design Of Organic Semiconductors For Interfacial And Emissive Material Applications, Marcus David Cole Mar 2020

Molecular Design Of Organic Semiconductors For Interfacial And Emissive Material Applications, Marcus David Cole

Doctoral Dissertations

This dissertation describes the synthesis and characterization of functional optoelectronically active materials. Synthetic techniques were used to prepare polymers containing perylene diimide (PDI) or tetraphenylethylene (TPE) moieties in the polymer backbone. PDI-based structures were prepared with embedded cationic or zwitterionic moieties intended to tailor organic/inorganic interfaces in thin film photovoltaic devices. The aggregation-induced emission (AIE)-active TPE polymers were synthesized to study how AIE properties evolve in π-conjugated polymers. The syntheses discussed here focused on modulation of molecular architecture to give rise to materials with tailored optoelectronic properties.

Chapter 1 provides a brief overview of the field of organic ...


Motion Segmentation - Segmentation Of Independently Moving Objects In Video, Pia Katalin Bideau Mar 2020

Motion Segmentation - Segmentation Of Independently Moving Objects In Video, Pia Katalin Bideau

Doctoral Dissertations

The ability to recognize motion is one of the most important functions of our visual system. Motion allows us both to recognize objects and to get a better understanding of the 3D world in which we are moving. Because of its importance, motion is used to answer a wide variety of fundamental questions in computer vision such as: (1) Which objects are moving independently in the world? (2) Which objects are close and which objects are far away? (3) How is the camera moving?
My work addresses the problem of moving object segmentation in unconstrained videos. I developed a probabilistic ...


Integrative Experience: Soil Microbes And The Sustainability Of Organic Agriculture, Kristen Deangelis, Luiz Domeignoz Horta Jan 2020

Integrative Experience: Soil Microbes And The Sustainability Of Organic Agriculture, Kristen Deangelis, Luiz Domeignoz Horta

Microbiology Educational Materials

This curriculum describes a one-unit course designed to fulfill the University of Massachusetts requirement for Integrative Experience as part of the Gen Ed curriculum for undergraduates.


Acquisition Of Inflectional Morphology In Artificial Neural Networks With Prior Knowledge, Katharina Kann Jan 2020

Acquisition Of Inflectional Morphology In Artificial Neural Networks With Prior Knowledge, Katharina Kann

Proceedings of the Society for Computation in Linguistics

How does knowledge of one language’s morphology influence learning of inflection rules in a second one? In order to investigate this question in artificial neural network models, we perform experiments with a sequence-to-sequence architecture, which we train on different combinations of eight source and three target languages. A detailed analysis of the model outputs suggests the following conclusions: (i) if source and target language are closely related, acquisition of the target language’s inflectional morphology constitutes an easier task for the model; (ii) knowledge of a prefixing (resp. suffixing) language makes acquisition of a suffixing (resp. prefixing) language’s ...


Multi-Input Strictly Local Functions For Templatic Morphology, Hossep Dolatian, Jonathan Rawski Jan 2020

Multi-Input Strictly Local Functions For Templatic Morphology, Hossep Dolatian, Jonathan Rawski

Proceedings of the Society for Computation in Linguistics

This paper presents an automata-theoretic characterization of templatic morphology. We generalize the Input Strictly Local class of functions, which characterize a majority of concatenative morphology, to consider multiple lexical inputs. We show that strictly local asynchronous multi-tape transducers successfully capture this typology of nonconcatenative template filling. This characterization and restriction uniquely opens up representational issues in morphological computation


The Role Of Linguistic Features In Domain Adaptation: Tag Parsing Of Questions, Aarohi Srivastava, Robert Frank, Sarah Widder, David Chartash Jan 2020

The Role Of Linguistic Features In Domain Adaptation: Tag Parsing Of Questions, Aarohi Srivastava, Robert Frank, Sarah Widder, David Chartash

Proceedings of the Society for Computation in Linguistics

The analysis of sentences outside the domain of the training data poses a challenge for contemporary syntactic parsing. The Penn Treebank corpus, commonly used for training constituency parsers, systematically undersamples certain syntactic structures. We examine parsing performance in Tree Adjoining Grammar (TAG) on one such structure: questions. To avoid hand-annotating a new training set including out-of-domain sentences, an expensive process, an alternate method requiring considerably less annotation effort is explored. Our method is based on three key ideas: First, pursuing the intuition that “supertagging is almost parsing” (Bangalore and Joshi, 1999), the parsing process is decomposed into two distinct stages ...


Multi-Input Strict Local Functions For Tonal Phonology, Jonathan Rawski, Hossep Dolatian Jan 2020

Multi-Input Strict Local Functions For Tonal Phonology, Jonathan Rawski, Hossep Dolatian

Proceedings of the Society for Computation in Linguistics

This paper presents an automata-theoretic characterization of the typology of attested tonal patterns using enriched data structures. We generalize the Input Strictly Local class of functions to consider multiple inputs of tonal and segmental strings, and find that the associated strictly local multi-tape transducers successfully capture tonal typology. Links between automata-theoretic and logical characterizations of phonological expressivity showcase the tradeoffs in data structure and locality in the expressivity of phonological computation.


Supporting Proactive Management In The Context Of Climate Change: Prioritizaing Range-Shifting Invasive Plants Based On Impact, Mei Rockwell-Postel, Brittany B. Laginhas, Bethany A. Bradley Jan 2020

Supporting Proactive Management In The Context Of Climate Change: Prioritizaing Range-Shifting Invasive Plants Based On Impact, Mei Rockwell-Postel, Brittany B. Laginhas, Bethany A. Bradley

Environmental Conservation Faculty Publication Series

Non-native, invasive plants are projected to shift their ranges with climate change, creating hotspots of risk where a multitude of novel species may soon establish and spread. The Northeast U.S. is one such hotspot. However, because monitoring for novel species is costly, these range-shifting invasive plants need to be prioritized. Preventing negative impacts is a key goal of management, thus, comparing the potential impacts of range-shifting invasive species could inform this prioritization. Here, we adapted the Environmental Impacts Classification for Alien Taxa (EICAT) protocol to evaluate potential impacts of 100 invasive plants that could establish either currently or by ...


Examining The Complex Relationship Between Innovation And Regulation Through A Survey Of Wastewater Utility Managers, Luke Sherman, Alida Cantor, Anita Milman, Michael Kiparsky Jan 2020

Examining The Complex Relationship Between Innovation And Regulation Through A Survey Of Wastewater Utility Managers, Luke Sherman, Alida Cantor, Anita Milman, Michael Kiparsky

Environmental Conservation Faculty Publication Series

Despite pressures to increase performance and decrease costs, innovation has been slow to emerge in the municipal wastewater sector. The relationship between regulation and innovation in this sector is a particularly interesting aspect of this conundrum, given the degree to which public utility decision-making is influenced by regulation. Using a national survey, this paper examines US wastewater utility managers’ perceptions of how regulation influences the adoption of new technologies. Recognizing that the relationship between innovation and regulation is complex, we develop the concept of regulation as multifaceted and examine three interrelated aspects of regulation: (1) regulatory requirements, (2) regulators and ...


Dam Impoundments Sediment Mass – Tributaries To The Hudson River, Brian Yellen, Jonathan Woodruff Jan 2020

Dam Impoundments Sediment Mass – Tributaries To The Hudson River, Brian Yellen, Jonathan Woodruff

Data and Datasets

This repository contains data from sediment cores collected during 2017-2018 from 17 impoundments that are located on tributaries to the tidal portion of the Hudson River as part of a larger NERRs collaborative project entitled Dams and Sediment on the Hudson (DaSH). A companion dataset that contains sediment core data from Hudson tidal marshes is archived at UMass Scholarworks data repository. Sediment cores collected from impoundments behind dams were recovered via piston push coring, which tends to minimize compaction and be representative of true sediment thicknesses. The general workflow for cores included (1) splitting; (2) Itrax XRF scanning; (3) subsampling ...


Hudson River Estuary Tidal Marsh Sediment Data, Brian Yellen, Jonathan Woodruff Jan 2020

Hudson River Estuary Tidal Marsh Sediment Data, Brian Yellen, Jonathan Woodruff

Data and Datasets

This repository contains data from sediment cores collected at six tidal wetland complexes that are located within the Hudson River Estuary. The sites include Stockport Marsh, Esopus Delta, Tivoli North Bay, Tivoli South Bay, Vanderburgh Cove, and Iona Island Marsh. A variety of core collection tools and methods were used to collect uncompacted records, including gouge coring, Russian peat coring, and piston push coring, with the method determined by coring environment. The general workflow for cores included (1) splitting; (2) Itrax XRF scanning; (3) subsampling cores ~10 cm spacing; (4) drying and burning samples for percent water, organic, and mineral ...


Agenda, Shubha Tewari Jan 2020

Agenda, Shubha Tewari

Science and Engineering Saturday Seminars

Abstracts for six Science and Engineering Saturday Seminars.


. Arduino Microcontrollers In The Classroom: Teaching How To Phrase Effective Science Questions And How To Answer Them With Original Data, Tony Dinsmore Jan 2020

. Arduino Microcontrollers In The Classroom: Teaching How To Phrase Effective Science Questions And How To Answer Them With Original Data, Tony Dinsmore

Science and Engineering Saturday Seminars

Arduino microcontrollers in the classroom: teaching how to phrase effective science questions and how to answer them with original data. Prof. Tony Dinsmore, UMass Physics This workshop will develop course modules that address a challenge in the science curriculum: how do we teach basic problem-solving and curiosity-based research skills in a classroom setting? The standard science curriculum teaches concepts and theory quite well but leaves rather little opportunity for students to take the lead in designing and implementing their own investigations. The workshop will use the Arduino, an inexpensive microcontroller that is simple to set up. A huge range of ...


Agenda, Revised, Shubha Tewari Jan 2020

Agenda, Revised, Shubha Tewari

Science and Engineering Saturday Seminars

Materials from the seminars. The agenda was revised to include online sessions due to the Covid-19 pandemic.


Elliptic Curves And Power Residues, Vy Thi Khanh Nguyen Nov 2019

Elliptic Curves And Power Residues, Vy Thi Khanh Nguyen

Doctoral Dissertations

Let E1 x E2 over Q be a fixed product of two elliptic curves over Q with complex multiplication. I compute the probability that the pth Fourier coefficient of E1 x E2, denoted as ap(E1) + ap(E2), is a square modulo p. The results are 1/4, 7/16, and 1/2 for different imaginary quadratic fields, given a technical independence of the twists. The similar prime densities for cubes and 4th power are 19/54, and 1/4, respectively. I also compute the probabilities without the technical assumption on ...


Petrogenesis Of Basaltic Lavas In Iceland And The Springerville Volcanic Field, U.S.A.: The Influence Of Tectonic Setting, Depth Of Melting And Volatiles, Marissa Mnich Nov 2019

Petrogenesis Of Basaltic Lavas In Iceland And The Springerville Volcanic Field, U.S.A.: The Influence Of Tectonic Setting, Depth Of Melting And Volatiles, Marissa Mnich

Doctoral Dissertations

Icelandic basalts were long thought to be low in water (e.g. Gunnarsson et al., 1998), but more recent studies suggest that hotspots, like the Iceland mantle plume, may be a source of hydrous basaltic melts (Nichols et al., 2002). To explore a possible link between location, volatile concentration and resulting petrogenetic implications, samples were collected from eleven volcanic centers throughout Iceland. Water concentrations were measured in melt inclusions and phenocrysts using Fourier transform infrared (FTIR) spectroscopy. Results for a subset of samples indicate variable water in melt inclusions ranging from approximately 50 ppm to over 3000 ppm. Samples from ...