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University of Massachusetts Amherst

Theses/Dissertations

2009

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Tyrosine Phosphorylation Events In Mouse Sperm Capacitation, Enid Arcelay Sep 2009

Tyrosine Phosphorylation Events In Mouse Sperm Capacitation, Enid Arcelay

Open Access Dissertations

Mammalian sperm are not able to fertilize immediately upon ejaculation; they become fertilization-competent after undergoing changes in the female reproductive tract collectively termed capacitation. Although it has been established that capacitation is associated with an increase in tyrosine phosphorylation, little is known about the role of this event in sperm function. In this work we used a combination of two dimensional gel electrophoresis and mass spectrometry to identify proteins that undergo tyrosine phosphorylation during capacitation. Some of the identified proteins are the mouse orthologues of human sperm proteins known to undergo tyrosine phosphorylation. Among them we identified VDAC, tubulin, PDH …

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Improved Network Consistency And Connectivity In Mobile And Sensor Systems, Nilanjan Banerjee Sep 2009

Improved Network Consistency And Connectivity In Mobile And Sensor Systems, Nilanjan Banerjee

Open Access Dissertations

Edge networks such as sensor, mobile, and disruption tolerant networks suffer from topological uncertainty and disconnections due to myriad of factors including limited battery capacity on client devices and mobility. Hence, providing reliable, always-on consistency for network applications in such mobile and sensor systems is non-trivial and challenging. However, the problem is of paramount importance given the proliferation of mobile phones, PDAs, laptops, and music players. This thesis identifies two fundamental deterrents to addressing the above problem. First, limited energy on client mobile and sensor devices makes high levels of consistency and availability impossible. Second, unreliable support from the network …

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“Obscene Fantasies”: Elfriede Jelinek’S Generic Perversions, Brenda L. Bethman Sep 2009

“Obscene Fantasies”: Elfriede Jelinek’S Generic Perversions, Brenda L. Bethman

Open Access Dissertations

This dissertation examines Elfriede Jelinek’s investigation of Austria’s and Western Europe’s “obscene fantasies” through her “perversion” of generic forms in three of her best-known texts (Die Liebhaberinnen, Lust, and Die Klavierspielerin). It also investigates how these texts, at first glance less overtly political than Jelinek’s later work, can be seen as laying the groundwork for her later, more political, analysis of Austrian fascism and racism. The dissertation is composed of three chapters; each investigates a central psychoanalytic concept (alienation, jouissance, perversion and sublimation) and reads a Jelinek text in relation to the genre that it is perverting, exposing the “obscene …

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Composition As Identity: A Study In Ontology And Philosophical Logic, Einar Bohn Sep 2009

Composition As Identity: A Study In Ontology And Philosophical Logic, Einar Bohn

Open Access Dissertations

In this work I first develop, motivate, and defend the view that mereological composition, the relation between an object and all its parts collectively, is a relation of identity. I argue that this view implies and hence can explain the logical necessity of classical mereology, the formal study of the part-whole relation. I then critically discuss four contemporary views of the same kind. Finally, I employ my thesis in a recent discussion of whether the world is fundamentally one in number.

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The Role Of Program Evaluations In Improving And Sustaining State-Supported School Counseling Programs: A Cross Case Analysis Of Best Practices, Ian Monteg Martin Sep 2009

The Role Of Program Evaluations In Improving And Sustaining State-Supported School Counseling Programs: A Cross Case Analysis Of Best Practices, Ian Monteg Martin

Open Access Dissertations

Recent work has shown that many state supported school counseling programs have not developed working statewide program evaluation schemas. This study examined two exemplary examples of state level program evaluation. Mixed-method case studies were created and then analyzed across cases to reveal common themes and best practices. The findings indicated that these cases were able to build statewide evaluation capacity within very different contexts.

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Writing Across The Curriculum Program Development As Ideological And Rhetorical Practice, Carolyn J. Fulford Sep 2009

Writing Across The Curriculum Program Development As Ideological And Rhetorical Practice, Carolyn J. Fulford

Open Access Dissertations

Few research studies have focused on WAC program development. Those that exist do not examine the ideological grounds for programmatic changes. This dissertation explores the dynamics of such changes through a four-year ethnographic study of WAC program development at a small, public, liberal arts college. The study employed extensive participant observation, interviewing, and document collection to trace how curricular and cultural changes around writing take shape and what ideologies and rhetorical practices come into play during that complex change process. The site for the study is of special interest because WAC there was in transition from an informal coalition focused …

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An Empirical Analysis Of Environmental Uncertainty, Realoptions Decision Patterns And Firm Performance, Alfred M. Boccia Jr. Sep 2009

An Empirical Analysis Of Environmental Uncertainty, Realoptions Decision Patterns And Firm Performance, Alfred M. Boccia Jr.

Open Access Dissertations

Real options theory has become an influential explanatory and normative framework for making resource allocation decisions. Despite a growing body of strategy research regarding real options, however, there is as of yet little empirical confirmation (1) that firm resource allocation behavior conforms with real options theory, or (2) that employing real options principles has a positive impact on firm performance. This research examines these questions. Using a survey instrument designed to measure a range of real options-theoretic decision patterns, data has been collected from a sample of 173 U.S. manufacturing firms. This data set has been used to test two …

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Management Of Target-Tracking Sensor Networks, Khaled Hadi Sep 2009

Management Of Target-Tracking Sensor Networks, Khaled Hadi

Open Access Dissertations

Target tracking has emerged as an important application of sensor networks. There are two subproblems inherent to target tracking. The first is the initial location of the target as it enters the region being covered. The second is following its track once it has been discovered. In this work, we outline an approach to target tracking. We present an energy-aware tracking algorithm that predicts the target track and activates nodes based on that prediction. We then discuss different energy management schemes that resolve tradeoffs between energy savings and track quality for a specified mission lifetime. Our energy management schemes perform …

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Ciliate Biodiversity And Phylogenetic Reconstruction Assessed By Multiple Molecular Markers, Micah Dunthorn Sep 2009

Ciliate Biodiversity And Phylogenetic Reconstruction Assessed By Multiple Molecular Markers, Micah Dunthorn

Open Access Dissertations

Ciliates provide a powerful system within microbial eukaryotes in which molecular genealogies can be compared to detailed morphological taxonomies. Two groups with such detailed taxonomies are the Colpodea and the Halteriidae. There are about 200 described Colpodea species that are found primarily in terrestrial habitats. In Chapters 1 and 2, taxon sampling is increased to include exemplars from all major subclades using nuclear small subunit rDNA (nSSU-rDNA) sequencing. Much of the morphological taxonomy is supported, but extensive non-monophyly is found throughout. The conflict between some nodes of the nSSU-rDNA genealogy and morphology-based taxonomy suggests the need for additional molecular marker. …

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Application Of Driver Behavior And Comprehension To Dilemma Zone Definition And Evaluation, David S. Hurwitz Sep 2009

Application Of Driver Behavior And Comprehension To Dilemma Zone Definition And Evaluation, David S. Hurwitz

Open Access Dissertations

Among the most critical elements at signalized intersections are the design of vehicle detection equipment and the timing of change and clearance intervals. Improperly timed clearance intervals or improperly placed detection equipment can potentially place drivers in a Type I dilemma zone, where approaching motorists can neither proceed through the intersection before opposing traffic is released nor safely stop in advance of the stop bar. Type II dilemma zones are not necessarily tied to failures in design, but are more readily tied to difficulties in driver decision making associated with comprehension and behavior. The Type II dilemma zone issues become …

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Climate And Environmental Change In Arctic Canada: Observations From Upper And Lower Murray Lakes, Ellesmere Island, Nunavut, Timothy Cook Sep 2009

Climate And Environmental Change In Arctic Canada: Observations From Upper And Lower Murray Lakes, Ellesmere Island, Nunavut, Timothy Cook

Open Access Dissertations

This study was designed with the overriding goal of improving our understanding of the nature, causes, and impacts of past climatic conditions in the High Arctic and to evaluate the potential impacts of future climatic warming. Specifically, the focus of this project was centered on Upper and Lower Murray Lakes (81° 21’ N, 69° 32’ W) on northern Ellesmere Island, Nunavut, Canada. Sediment cores were collected from each of the lakes in order to reconstruct past climate and environmental variability and space-borne synthetic aperture radar (SAR) data were used to evaluate recent variability in the ice cover of these lakes. …

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Development Of Structured Delivery Systems Using Nanolaminated Biopolymer Layers, Young-Hee Cho Sep 2009

Development Of Structured Delivery Systems Using Nanolaminated Biopolymer Layers, Young-Hee Cho

Open Access Dissertations

The objectives of this study were to carry out research to better understand of the formation, stability and properties of multilayer emulsions containing nano-laminated biopolymer coatings, and to utilize this information to develop food-grade delivery systems. The effect of various preparation parameters on the formation and stability of multilayer emulsions was investigated: droplet concentration; mean droplet diameter; droplet charge; biopolymer concentration. β-lactoglobulin (β-Lg) stabilized emulsions (0.5 – 10 wt% oil) containing different pectin concentrations (0 to 0.5 wt%) were prepared at pH 7 (where lipid droplets and pectin molecules were both anionic) and pH 3.5 (where lipid droplets were cationic …

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Investigations Into The Potential For 3,4-Methylenedioxymethamphetamine To Induce Neurotoxic Terminal Damage To Serotonergic Neurons, Dominik Biezonski Sep 2009

Investigations Into The Potential For 3,4-Methylenedioxymethamphetamine To Induce Neurotoxic Terminal Damage To Serotonergic Neurons, Dominik Biezonski

Open Access Dissertations

High doses of 3,4-methylenedioxymethamphetamine (MDMA; "Ecstasy") are known to reduce levels of various serotonergic markers outside of the raphe nuclei. To test the hypothesis that these deficits reflect a degeneration of distal axons/terminals, we investigated the effects of an MDMA binge (10mg/kg x 4) on the relative protein and genetic expression of several serotonergic markers in rats, as well as the effects of this compound on the quantity of serotonergic terminals in these animals. In experiment I, we examined whether MDMA alters serotonin transporter (SERT) levels as determined by lysate binding and immunoblotting analyses. Both methods of analysis revealed MDMA-induced …

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Distribution And Diversity Of Planktonic Ciliates: Patterns And Processes, Mary Doherty Sep 2009

Distribution And Diversity Of Planktonic Ciliates: Patterns And Processes, Mary Doherty

Open Access Dissertations

The nature and extent of microbial biodiversity remain controversial with persistent debates over patterns of distributions (i.e. cosmopolitanism vs. endemism) and the processes that structure these patterns (neutrality vs. selection). We used culture-independent approaches to address these issues focusing on two groups of ciliates, the Oligotrichia (Spirotrichea) and Choreotrichea (Spirotrichea). To assess the diversity of these ciliates, we designed primers specific to SSU rDNA of ciliates within these clades, and investigated (1) geographic and temporal distributions along three coastal sites in the Northwest Atlantic; (2) the relationship between ciliate communities in the benthos and the plankton along the New England …

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The Development Of Hierarchical Knowledge In Robot Systems, Stephen W. Hart Sep 2009

The Development Of Hierarchical Knowledge In Robot Systems, Stephen W. Hart

Open Access Dissertations

This dissertation investigates two complementary ideas in the literature on machine learning and robotics--those of embodiment and intrinsic motivation--to address a unified framework for skill learning and knowledge acquisition. "Embodied" systems make use of structure derived directly from sensory and motor configurations for learning behavior. Intrinsically motivated systems learn by searching for native, hedonic value through interaction with the world. Psychological theories of intrinsic motivation suggest that there exist internal drives favoring open-ended cognitive development and exploration. I argue that intrinsically motivated, embodied systems can learn generalizable skills, acquire control knowledge, and form an epistemological understanding of the world …

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Managing Audits To Manage Earnings: The Impact Of Baiting Tactics On An Auditor’S Ability To Uncover Earnings Management Errors, Benjamin Labrie Luippold Sep 2009

Managing Audits To Manage Earnings: The Impact Of Baiting Tactics On An Auditor’S Ability To Uncover Earnings Management Errors, Benjamin Labrie Luippold

Open Access Dissertations

This study examines an aspect of earnings management that I refer to as audit management. I define audit management as a client's strategic use of techniques (e.g., baiting tactics) to prevent auditors from discovering earnings management during the audit. Specifically, I examine whether two baiting tactics, diversionary statements and distracting errors, affect an auditor's ability to uncover an accounting error used to manage earnings. Auditors performed analytical review on financial statements that contained an earnings management error (i.e., an intentional error that results in the client meeting an earnings target). I manipulated whether management provided a diversionary statement that explicitly …

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Tailoring The Surface-Coating Of Gold Nanoparticles For Bio-Applications, Partha S. Ghosh Sep 2009

Tailoring The Surface-Coating Of Gold Nanoparticles For Bio-Applications, Partha S. Ghosh

Open Access Dissertations

Functionalized gold nanoparticles (AuNPs) provide an excellent scaffold for numerous biological applications. In these systems, the gold core imparts stability to the assembly, while the monolayer allows tuning of surface characteristics such as charge and hydrophobicity. The nano-scale size and tunable surface properties have made them an ideal candidate for manipulating protein-protein/protein-nucleic acid interactions, and delivery of therapeutics. In this thesis work, it has been demonstrated how the surface coating plays an important role in achieving a desired goal. Using organic synthesis as a tool, the monolayer was tailored to afford useful particles with biocompatibility and the ability to respond …

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Intermolecular Electron Transfer Reactivity And Dynamics Of Cytochrome C – Nanoparticle Adducts, Adrienne M. Carver Sep 2009

Intermolecular Electron Transfer Reactivity And Dynamics Of Cytochrome C – Nanoparticle Adducts, Adrienne M. Carver

Open Access Dissertations

Interprotein electron transfer (ET) is crucial for natural energy conversion and a fundamental reaction in the pursuit of understanding the broader problem of proteinprotein interactions and reactivity. Simplifying the complicated nature of these natural systems has driven development of biomimetic approaches. Functionalized gold nanoparticles offer simplified, tunable surfaces that can serve as a proxy to study the reactivity and dynamics of proteins. Amino-acid functionalized gold nanoparticles (Au-TX) served as a complementary partner to cytochrome c (Cyt c) and catalyzed its ET reactivity without altering the native structure. Redox mediator and EPR experiments confirmed that the redox potential and coordination environment …

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Synthesis And Study Of Hybrid Organic – Inorganic Polyhedral Oligomeric Silsesquioxanes (Poss) Based Polymers, Gunjan A, Gadodia Sep 2009

Synthesis And Study Of Hybrid Organic – Inorganic Polyhedral Oligomeric Silsesquioxanes (Poss) Based Polymers, Gunjan A, Gadodia

Open Access Dissertations

Hybrid organic-inorganic materials represent a new class of materials having scientific and technological potential. In this thesis, Polyhedral Oligomeric Silsesquioxanes (POSS) are used as an inorganic building block which has been tethered to an organic polymer. POSS are silica precusors, having a well defined silsesquioxane cental core surrounded by an organic periphery which makes them compatible with monomers and possibly polymers. The objectives of this study are to (1) study the basic structures of POSS homopolymers, (2) to incorporate POSS building blocks by a bottomup approach into polymer chains and study the resulting morphologies, and (3) to study the thin …

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Sensor Control And Scheduling Strategies For Sensor Networks, Victoria U. Manfredi Sep 2009

Sensor Control And Scheduling Strategies For Sensor Networks, Victoria U. Manfredi

Open Access Dissertations

We investigate sensor control and scheduling strategies to most effectively use the limited resources of an ad hoc network or closed-loop sensor network. In this context, we examine the following three problems. Where to focus sensing? Certain types of sensors, such as cameras or radars, are unable to simultaneously collect high fidelity data from all environmental locations, and thus require some sort of sensing strategy. Considering a meteorological radar network, we show that the main benefits of optimizing sensing over expected future states of the environment are when there are multiple small phenomena in the environment. Considering multiple users, we …

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Essays On Environmental Policy And Markets, Linus M. Nyiwul Sep 2009

Essays On Environmental Policy And Markets, Linus M. Nyiwul

Open Access Dissertations

This dissertation consists of two theoretical papers on market-based environmental policy. The first paper exploits the correlation between the environmental performance of firms and their economic performance to show that financial markets can be used to help enforce environmental policy and to design more efficient regulations. The results indicate that when markets punish firms for not complying with environmental standards, environmental regulators can exploit this by setting stricter standards. In fact, it is possible for the regulator to use market-driven enforcement to reduce a firm’s emissions and monitoring of the firm simultaneously. The second paper provides a theoretical analysis of …

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Normal And Extreme Sedimentation And Physical Processes In Lake Tuborg, Ellesmere Island, Nunavut, Edward Lewis Sep 2009

Normal And Extreme Sedimentation And Physical Processes In Lake Tuborg, Ellesmere Island, Nunavut, Edward Lewis

Open Access Dissertations

Lake Tuborg is a large lake on west-central Ellesmere Island, Nunavut. Part of the lake is meromictic, and contains trapped saltwater below about 55 m depth. The lake receives meltwater and sediments from multiple sources, including snowmelt and glacier melt. A lake process study was undertaken from 2001-2003 at Lake Tuborg that involved obtaining profiles of water temperature, salinity, transmissivity, and dissolved oxygen. Networks of short and long sediment cores were also obtained throughout the lake. During the last year of monitoring the lake and its sediments, a large catastrophic drainage of an ice-dammed lake occurred (a jökulhlaup). This was …

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High Temperature Proton Conducting Materials And Fluorescent-Labeled Polymers For Sensor Applications, Surangkhana Martwiset Sep 2009

High Temperature Proton Conducting Materials And Fluorescent-Labeled Polymers For Sensor Applications, Surangkhana Martwiset

Open Access Dissertations

The majority of this dissertation focuses on proton conducting materials that could be used at high operating temperatures. Higher operating temperatures are desirable as they will increase fuel cell efficiency, reduce cost, and simplify the heat management system. The factors governing proton conduction including segmental mobility, protogenic group identity, and charge carrier density were investigated on a variety of polymers containing 1H-1,2,3-triazole moieties. Proton conductivity measurements were made using AC impedance spectroscopy. Random copolymers and terpolymers of triazole-containing acrylates and poly(ethylene glycol)methyl ether acrylate (PEGMEA) have been synthesized. Conductivity increased with increasing degree of PEG incorporation until reaching a maximum …

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Investigation Of Fe(Iii) Reduction In Geobacter Sulfurreducens Characterization Of Outer Surface Associated Electron Transfer Components, Xenlei Qian Sep 2009

Investigation Of Fe(Iii) Reduction In Geobacter Sulfurreducens Characterization Of Outer Surface Associated Electron Transfer Components, Xenlei Qian

Open Access Dissertations

Outer membrane cytochromes OmcB and OmcS of Geobacter sulfurreducens are two important components of the respiratory chain for extracellular Fe(III) reduction. OmcS is a loosely bound cell surface protein involved in the reduction of insoluble Fe(III). OmcB is an outer membrane protein and required for insoluble and soluble Fe(III) reduction. The objective of this study was to understand better the mechanism of dissimilatory Fe(III) reduction, focusing on the cell surface proteins by further localization, identification of protein-protein interactions, and biochemical characterization of OmcB and OmcS. OmcB was found to be surface-exposed but embedded in the outer membrane because mild protease …

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Formulating Older Driver Licensing Policy: An Evaluation Of Older Driver Crash History And Performance, Heather A. Rothenberg Sep 2009

Formulating Older Driver Licensing Policy: An Evaluation Of Older Driver Crash History And Performance, Heather A. Rothenberg

Open Access Dissertations

This research sought to understand the relationship between licensing policy and the opportunity for the development of a scientifically-based approach to identifying high risk older drivers based on prior driving history. This research focused on five tasks: 1) review of the literature, 2) compilation of information on licensing policy for use by decision-makers, 3) assessment of charges and payer source for older driver crashes using linked crash and hospital data , and 4) the development and 5) validation of an older driver crash prediction model. There is relatively little available in the way of information for policymakers regarding licensing, and …

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Natural Selection And The Syntax Of Clausal Complementation, Keir Moulton Sep 2009

Natural Selection And The Syntax Of Clausal Complementation, Keir Moulton

Open Access Dissertations

This dissertation examines the syntax and semantics of clausal complements. It identifies semantic underpinnings for some syntactic properties of the arguments of propositional attitude verbs. The way clausal arguments compose with their embedding predicates is not uniform and semantic differences emerge from the syntactic context clausal arguments appear in. Three case studies are taken up: clausal arguments of nouns, dislocated clausal arguments (sentential subjects and topics), and infinitival complements with overt subjects (AcI constructions). Chapter Two assembles evidence to support Stowell’s (1981) claim that the clausal complements of nouns are modifiers. It is shown that the clausal complements of nouns …

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Essays On Financial Behavior And Its Macroeconomic Causes And Implications, Soon Ryoo Sep 2009

Essays On Financial Behavior And Its Macroeconomic Causes And Implications, Soon Ryoo

Open Access Dissertations

This dissertation consists of three independent essays. The first essay, “Long Waves and Short Cycles in a Model of Endogenous Financial Fragility,” presents a stock flow consistent macroeconomic model in which financial fragility in firm and household sectors evolves endogenously through the interaction between real and financial sectors. Changes in firms’ and households’ financial practices produce long waves. The Hopf bifurcation theorem is applied to clarify the conditions for the existence of limit cycles, and simulations illustrate stable limit cycles. The long waves are characterized by periodic economic crises following long expansions. Short cycles, generated by the interaction between effective …

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Seasonal Home Range Sizes, Transboundary Movements And Conservation Of Elephants In Northern Tanzania, Alfred P. Kikoti Sep 2009

Seasonal Home Range Sizes, Transboundary Movements And Conservation Of Elephants In Northern Tanzania, Alfred P. Kikoti

Open Access Dissertations

Although the unprotected lands of northern Tanzania support large numbers of elephants, and provide critical linkages for wildlife movements across the region, there is little information on the dispersal patterns of elephants in these unprotected lands. Our home range measures (100% MCP) of 21 elephants with satellite collars in four study regions were highly variable (191 to 3,698 km2). Home range sizes (95% fixed kernel) of bulls were typically larger than those of females, and wet season ranges were typically larger than dry season ranges. There were large differences in average home range sizes reflected varying strategies for obtaining food …

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Action-Based Representation Discovery In Markov Decision Processes, Sarah Osentoski Sep 2009

Action-Based Representation Discovery In Markov Decision Processes, Sarah Osentoski

Open Access Dissertations

This dissertation investigates the problem of representation discovery in discrete Markov decision processes, namely how agents can simultaneously learn representation and optimal control. Previous work on function approximation techniques for MDPs largely employed hand-engineered basis functions. In this dissertation, we explore approaches to automatically construct these basis functions and demonstrate that automatically constructed basis functions significantly outperform more traditional, hand-engineered approaches. We specifically examine two problems: how to automatically build representations for action-value functions by explicitly incorporating actions into a representation, and how representations can be automatically constructed by exploiting a pre-specified task hierarchy. We first introduce a technique for …

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More Than One River: Local, Place-Based Knowledge And The Political Ecology Of Restoration And Remediation Along The Lower Neponset River, Massachusetts, Simona Lee Perry Sep 2009

More Than One River: Local, Place-Based Knowledge And The Political Ecology Of Restoration And Remediation Along The Lower Neponset River, Massachusetts, Simona Lee Perry

Open Access Dissertations

This research is an exploration of the local, place-based knowledge surrounding a degraded urban river, the Lower Neponset River and Estuary in southern Boston Harbor, Massachusetts, and its environmental restoration. Through a mixed-methods approach to sociological inquiry that included 18-months of ethnographic interviews and participant observations, Geographic Information System (GIS) mapping, archival document research, and critical environmental history, it explores the different ways local citizens interpret the river as a place of historical importance, personal nostalgia, social and family networks, neighborhood legacies, aesthetics, economic security, danger, psychological refuge, ecology, and political power. Using an interpretive analysis of the narrative, visual, …

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