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Partial Expansion Of A Lipschitz Domain And Some Applications, Weifeng Qiu, Jay Gopalakrishnan Jan 2012

Partial Expansion Of A Lipschitz Domain And Some Applications, Weifeng Qiu, Jay Gopalakrishnan

Mathematics and Statistics Faculty Publications and Presentations

We show that a Lipschitz domain can be expanded solely near a part of its boundary, assuming that the part is enclosed by a piecewise C1 curve. The expanded domain as well as the extended part are both Lipschitz. We apply this result to prove a regular decomposition of standard vector Sobolev spaces with vanishing traces only on part of the boundary. Another application in the construction of low-regularity projectors into finite element spaces with partial boundary conditions is also indicated

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Mixed Finite Element Approximation Of The Vector Laplacian With Dirichlet Boundary Conditions, Douglas N. Arnold, Richard S. Falk, Jay Gopalakrishnan Jan 2012

Mixed Finite Element Approximation Of The Vector Laplacian With Dirichlet Boundary Conditions, Douglas N. Arnold, Richard S. Falk, Jay Gopalakrishnan

Mathematics and Statistics Faculty Publications and Presentations

We consider the finite element solution of the vector Laplace equation on a domain in two dimensions. For various choices of boundary conditions, it is known that a mixed finite element method, in which the rotation of the solution is introduced as a second unknown, is advantageous, and appropriate choices of mixed finite element spaces lead to a stable, optimally convergent discretization. However, the theory that leads to these conclusions does not apply to the case of Dirichlet boundary conditions, in which both components of the solution vanish on the boundary. We show, by computational example, that indeed such mixed …

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Wavenumber Explicit Analysis Of A Dpg Method For The Multidimensional Helmholtz Equation, Leszek Demkowicz, Jay Gopalakrishnan, Ignacio Muga, Jeffrey Zitelli Jan 2012

Wavenumber Explicit Analysis Of A Dpg Method For The Multidimensional Helmholtz Equation, Leszek Demkowicz, Jay Gopalakrishnan, Ignacio Muga, Jeffrey Zitelli

Mathematics and Statistics Faculty Publications and Presentations

We study the properties of a novel discontinuous Petrov Galerkin (DPG) method for acoustic wave propagation. The method yields Hermitian positive definite matrices and has good pre-asymptotic stability properties. Numerically, we find that the method exhibits negligible phase errors (otherwise known as pollution errors) even in the lowest order case. Theoretically, we are able to prove error estimates that explicitly show the dependencies with respect to the wavenumber ω, the mesh size h, and the polynomial degree p. But the current state of the theory does not fully explain the remarkably good numerical phase errors. Theoretically, comparisons are made with …

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A Class Of Discontinuous Petrov–Galerkin Methods. Part Iii: Adaptivity, Leszek Demkowicz, Jay Gopalakrishnan, Antti H. Niemi Jan 2012

A Class Of Discontinuous Petrov–Galerkin Methods. Part Iii: Adaptivity, Leszek Demkowicz, Jay Gopalakrishnan, Antti H. Niemi

Mathematics and Statistics Faculty Publications and Presentations

We continue our theoretical and numerical study on the Discontinuous Petrov–Galerkin method with optimal test functions in context of 1D and 2D convection-dominated diffusion problems and hp-adaptivity. With a proper choice of the norm for the test space, we prove robustness (uniform stability with respect to the diffusion parameter) and mesh-independence of the energy norm of the FE error for the 1D problem. With hp-adaptivity and a proper scaling of the norms for the test functions, we establish new limits for solving convection-dominated diffusion problems numerically: for 1D and for 2D problems. The adaptive process is fully automatic and starts …

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Benchmark Results For Testing Adaptive Finite Element Eigenvalue Procedures Ii (Cluster Robust Eigenvector And Eigenvalue Estimates), Stefano Giani, Luka Grubisic, Jeffrey S. Ovall Jan 2012

Benchmark Results For Testing Adaptive Finite Element Eigenvalue Procedures Ii (Cluster Robust Eigenvector And Eigenvalue Estimates), Stefano Giani, Luka Grubisic, Jeffrey S. Ovall

Mathematics and Statistics Faculty Publications and Presentations

As a model benchmark problem for this study we consider a highly singular transmission type eigenvalue problem which we study in detail both analytically as well as numerically. In order to justify our claim of cluster robust and highly accurate approximation of a selected groups of eigenvalues and associated eigenfunctions, we give a new analysis of a class of direct residual eigenspace/vector approximation estimates. Unlike in the first part of the paper, we now use conforming higher order finite elements, since the canonical choice of an appropriate norm to measure eigenvector approximation by discontinuous Galerkin methods is an open problem.

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Supporting Implementation Of The Common Core State Standards For Mathematics: Recommendations For Professional Development, Paola Sztajn, Karen A. Marrongelle, Peg Smith, Bonnie L. Melton Jan 2012

Supporting Implementation Of The Common Core State Standards For Mathematics: Recommendations For Professional Development, Paola Sztajn, Karen A. Marrongelle, Peg Smith, Bonnie L. Melton

Mathematics and Statistics Faculty Publications and Presentations

In 2010, the National Governor’s Association and the Council of Chief State School Officers published the Common Core State Standards for Mathematics (CCSSM) and to date, 44 states, the District of Columbia, and the U.S. Virgin Islands have adopted the document. These content and practice standards, which specify what students are expected to understand and be able to do in K-12 mathematics, represent a significant departure from what mathematics is currently taught in most classrooms and how it is taught. Developing teachers’ capacity to enact these new standards in ways that support the intended student learning outcomes will require considerable …

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People Of Snowy Mountain, People Of The River: A Multi-Agency Ethnographic Overview And Compendium Relating To Tribes Associated With Clark County, Nevada, Douglas Deur, Deborah Confer Jan 2012

People Of Snowy Mountain, People Of The River: A Multi-Agency Ethnographic Overview And Compendium Relating To Tribes Associated With Clark County, Nevada, Douglas Deur, Deborah Confer

Anthropology Faculty Publications and Presentations

The current document has been undertaken to assist agencies in meeting their obligations for federally mandated compliance and consultation with Indian tribes that have historical associations with Clark County. The document has been designed in part to provide an overview of the territorial associations of various tribes with ties to this area. This is accomplished using ethnohistorical documentation as well key legal documents, such as treaty language and Indian Claims Commission findings, that establish parameters for agency consultation responsibilities. Managers of Clark County’s federal lands have been eager to identify those tribes that are tied to the area in various …

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Compound Capillary Rise, Mark M. Weislogel Jan 2012

Compound Capillary Rise, Mark M. Weislogel

Mechanical and Materials Engineering Faculty Publications and Presentations

Irregular conduits, complex surfaces, and porous media often manifest more than one geometric wetting condition for spontaneous capillary flows. As a result, different regions of the flow exhibit different rates of flow, all the while sharing common dynamical capillary pressure boundary conditions. The classic problem of sudden capillary rise in tubes with interior corners is revisited from this perspective and solved numerically in the self-similar visco-capillary limit à laLucas–Washburn. Useful closed-form analytical solutions are obtained in asymptotic limits appropriate for many practical flows in conduits containing one or more interior corner. The critically wetted corners imbibe fluid away from …

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On The Effect Of Heterogeneity On The Dynamics And Performance Of Dynamical Networks, Alireza Goudarzi Jan 2012

On The Effect Of Heterogeneity On The Dynamics And Performance Of Dynamical Networks, Alireza Goudarzi

Dissertations and Theses

The high cost of processor fabrication plants and approaching physical limits have started a new wave research in alternative computing paradigms. As an alternative to the top-down manufactured silicon-based computers, research in computing using natural and physical system directly has recently gained a great deal of interest. A branch of this research promotes the idea that any physical system with sufficiently complex dynamics is able to perform computation. The power of networks in representing complex interactions between many parts make them a suitable choice for modeling physical systems. Many studies used networks with a homogeneous structure to describe the computational …

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Informal Learning Choices Of Japanese Esl Students In The United States, Brent Harrison Amburgey Jan 2012

Informal Learning Choices Of Japanese Esl Students In The United States, Brent Harrison Amburgey

Dissertations and Theses

This study was designed to explore possible relationships between English language learners past formal language learning experiences and beliefs about language learning on the one hand, and their informal learning choices on the other. Six Japanese English as a second language (ESL) students participated in the study. Participants were interviewed and asked to complete an English study log for one week prior to their scheduled interview. The results of the study suggested that there were likely connections between experiences, beliefs, informal learning choices. For some participants, a singular experience or belief had an effect that seemed to outweigh other experiences …

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Short-Term Plasticity At The Schaffer Collateral: A New Model With Implications For Hippocampal Processing, Andrew Hamilton Toland Jan 2012

Short-Term Plasticity At The Schaffer Collateral: A New Model With Implications For Hippocampal Processing, Andrew Hamilton Toland

Dissertations and Theses

A new mathematical model of short-term synaptic plasticity (STP) at the Schaffer collateral is introduced. Like other models of STP, the new model relates short-term synaptic plasticity to an interaction between facilitative and depressive dynamic influences. Unlike previous models, the new model successfully simulates facilitative and depressive dynamics within the framework of the synaptic vesicle cycle. The novelty of the model lies in the description of a competitive interaction between calcium-sensitive proteins for binding sites on the vesicle release machinery. By attributing specific molecular causes to observable presynaptic effects, the new model of STP can predict the effects of specific …

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Long-Term Responses Of Phalaris Arundinacea And Columbia River Bottomland Vegetation To Managed Flooding, Tina Schantz Farrelly Jan 2012

Long-Term Responses Of Phalaris Arundinacea And Columbia River Bottomland Vegetation To Managed Flooding, Tina Schantz Farrelly

Dissertations and Theses

I sought to determine the effect of managed flooding on Phalaris arundinacea L. and other plant species distributions in a large wetland complex, Smith and Bybee Wetlands (SBW), in northwestern Oregon. Altered hydrology has reduced historically high spring flow and prematurely initiated the historic summer drying period at SBW. This alteration has increased the coverage of invasive plants (e.g., P. arundinacea) causing a decrease in native plant cover and thus degrading ecological functions. SBW managers installed a water control structure (WCS) between SBW and the Columbia Slough/River system to impound winter rainfall and thus approximate the ecological benefits that natural …

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Are We Cool Yet?: A Longitudinal Content Analysis Of Nerd And Geek Representations In Popular Television, Christopher Louis Cardiel Jan 2012

Are We Cool Yet?: A Longitudinal Content Analysis Of Nerd And Geek Representations In Popular Television, Christopher Louis Cardiel

Dissertations and Theses

This study explores the representation of nerds and geeks in popular broadcast television programs over the course of the past twenty years. A content analysis of the five most popular scripted broadcast television programs for each year was conducted in order to assess the frequency of nerd characters, as well as the social competence, physical attractiveness, and demographic information of each such character. In addition, a supplemental survey design study was employed in order to collect public opinion data regarding perceptions of nerds in general and on television. The results of these studies indicated that while the per-year frequency of …

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Short Stories, Alisa Eve Welch Jan 2012

Short Stories, Alisa Eve Welch

Dissertations and Theses

In these six intertwining fictional short stories, one fateful decision ripples through the lives of multiple generations. Annie is an unmarried young mother during World War II when she leaves her young daughter in the care of a childless couple. When Annie fails to return for the child after days and then years, a new and fragile family is formed only to be tested by Annie's eventual return. The other stories in this collection follow the daughters and granddaughters who have to navigate their own lives in the shadow of this abandonment. Spanning multiple decades, Annie's decision remains a pivotal …

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A Data-Descriptive Feedback Framework For Data Stream Management Systems, Rafael J. Fernández Moctezuma Jan 2012

A Data-Descriptive Feedback Framework For Data Stream Management Systems, Rafael J. Fernández Moctezuma

Dissertations and Theses

Data Stream Management Systems (DSMSs) provide support for continuous query evaluation over data streams. Data streams provide processing challenges due to their unbounded nature and varying characteristics, such as rate and density fluctuations. DSMSs need to adapt stream processing to these changes within certain constraints, such as available computational resources and minimum latency requirements in producing results. The proposed research develops an inter-operator feedback framework, where opportunities for run-time adaptation of stream processing are expressed in terms of descriptions of substreams and actions applicable to the substreams, called feedback punctuations. Both the discovery of adaptation opportunities and the exploitation of …

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A Survey And Analysis Of Solutions To The Oblivious Memory Access Problem, Erin Elizabeth Chapman Jan 2012

A Survey And Analysis Of Solutions To The Oblivious Memory Access Problem, Erin Elizabeth Chapman

Dissertations and Theses

Despite the use of strong encryption schemes, one can still learn information about encrypted data using side channel attacks [2]. Watching what physical memory is being accessed can be such a side channel. One can hide this information by using oblivious simulation - hiding the true access pattern of a program. In this paper we will review the model behind oblivious simulation, attempt to formalize the problem and define a security game. We will review the major solutions pro- posed so far, the square root and hierarchical solutions, as well as propose a new variation on the square root solution. …

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The Basic Scheme For The Evaluation Of Functional Logic Programs, Arthur Peters Jan 2012

The Basic Scheme For The Evaluation Of Functional Logic Programs, Arthur Peters

Dissertations and Theses

Functional logic languages provide a powerful programming paradigm combining the features of functional languages and logic languages. However, current implementations of functional logic languages are complex, slow, or both. This thesis presents a scheme, called the Basic Scheme, for compiling and executing functional logic languages based on non-deterministic graph rewriting. This thesis also describes the implementation and optimization of a prototype of the Basic Scheme. The prototype is simple and performs well compared to other current implementations.

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Relative Heart Ventricle Mass And Cardiac Performance In Amphibians, Gregory Joseph Kluthe Jan 2012

Relative Heart Ventricle Mass And Cardiac Performance In Amphibians, Gregory Joseph Kluthe

Dissertations and Theses

This study used an in situ heart preparation to analyze the power and work of spontaneously beating hearts of four anurans (R. marina, L. catesbeianus, X. laevis, P. edulis) and three urodeles (N. maculosus, A. tigrinum, A. tridactylum) in order to elucidate the meaning of relative ventricle mass (RVM) in terms of specific cardiac performance variables. This study also tests two hypotheses: 1) the ventricles of terrestrial species (R. marina, P. edulis, A. tigrinum) of amphibians are capable of greater maximum power outputs (Pmax) compared to aquatic species (X. laevis, A. tridactylum, N. maculosus, L. catesbeianus) and, 2) …

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Evolved Design Of A Nonlinear Proportional Integral Derivative (Npid) Controller, Shubham Chopra Jan 2012

Evolved Design Of A Nonlinear Proportional Integral Derivative (Npid) Controller, Shubham Chopra

Dissertations and Theses

This research presents a solution to the problem of tuning a PID controller for a nonlinear system. Many systems in industrial applications use a PID controller to control a plant or the process. Conventional PID controllers work in linear systems but are less effective when the plant or the process is nonlinear because PID controllers cannot adapt the gain parameters as needed. In this research we design a Nonlinear PID (NPID) controller using a fuzzy logic system based on the Mamdani type Fuzzy Inference System to control three different DC motor systems. This fuzzy system is responsible for adapting the …

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Groundwater Surface Trends In The North Florence Dunal Aquifer, Oregon Coast, Usa, Sarah Rebecca Doliber Jan 2012

Groundwater Surface Trends In The North Florence Dunal Aquifer, Oregon Coast, Usa, Sarah Rebecca Doliber

Dissertations and Theses

The North Florence Dunal Aquifer is the only feasible source for drinking water for the coastal city of Florence, Oregon and Florence's Urban Growth Boundary. High infiltration rates and a shallow groundwater table leave the aquifer highly susceptible to contamination from septic tank effluent, storm runoff, chemical fertilizers and recreational ATV use throughout the dunes. Public interest in the quality and quantity of the aquifer water has been sparked since the City of Florence received a grant from the Environmental Protection Agency for a watershed protection and restoration project. Delineation of the shallow groundwater surface and its relationship to the …

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Understanding Sand Mining On The Maha Oya: The Conflict Between Economic And Environmental Survival, Meredith Corea Talbert Jan 2012

Understanding Sand Mining On The Maha Oya: The Conflict Between Economic And Environmental Survival, Meredith Corea Talbert

Dissertations and Theses

River sand mining from the Maha Oya is the main source of income and a force that drives economic activity for residents along the river. This study takes place in Sri Lanka, there are three villages included in this project: Jambugaswatte, Janituspuraya and Thoppuwa. In Sri Lanka, sand serves as the main building material. It is used to make bricks, tiles, asphalt and concrete, therefore demanding a high market value. However, the over-extraction of sand comes along with significant environmental problems. These communities depend on the river in many ways and the health of the river directly corresponds to the …

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Development And Implementation Of Acoustic Feedback Control For Scanning Probe Microscopy, Rodolfo Fernandez Rodriguez Jan 2012

Development And Implementation Of Acoustic Feedback Control For Scanning Probe Microscopy, Rodolfo Fernandez Rodriguez

Dissertations and Theses

A remote-sensing acoustic method for implementing position control feedback in Scanning Probe Microscopy (SPM) is presented. The capabilities of this feedback control using the new Whispering Gallery Acoustic Sensing (WGAS) method is demonstrated in a Shear-force Scanning Probe Microscope that uses a sharp probe attached to a piezoelectric Quartz Tuning Fork (QTF) firmly mounted on the microscope's frame. As the QTF is electrically driven its mechanical response reaches the SPM frame which then acts as a resonant cavity producing acoustic modes measured with an acoustic sensor strategically placed on the SPM head. The novelty of the WGAS resides in using …

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A Systems Approach To Ecological Economic Models Developed Progressively In Three Interwoven Articles, Takuro Uehara Jan 2012

A Systems Approach To Ecological Economic Models Developed Progressively In Three Interwoven Articles, Takuro Uehara

Dissertations and Theses

My dissertation develops and analyzes ecological economic models to study the complex dynamics of an ecological economic system (EES) and investigate various conditions and measures which can sustain a developing economy over the long term in view of resilience and sustainability. Because of the intrinsic complexity of the system, I take a systems approach, using economics as the foundation for the basic structure of an ecological economic model, and system dynamics as the method to build and analyze such a complex ecological economic model. Throughout my dissertation, the model developed by Brander and Taylor (1998) is adopted as a baseline …

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Sustainability Education As A Framework For Enhancing Environmental Stewardship In Young Leaders: An Intervention At Tryon Creek Nature Day Camp, Andrea Nicole Lawrence Jan 2012

Sustainability Education As A Framework For Enhancing Environmental Stewardship In Young Leaders: An Intervention At Tryon Creek Nature Day Camp, Andrea Nicole Lawrence

Dissertations and Theses

UNESCO established Sustainability Education as a top priority when it declared 2005 - 2014 to be the global decade for sustainability. Sustainability education can be implemented in outdoor programs such as nature summer camps in order to build environmental stewardship and ecological literacy in counselors and campers. This study sought to determine the extent to which an ecology and leadership training given to assistant counselors at Tryon Creek State Natural Area day camp achieved the goals of sustainability education--for the assistant counselors to learn about ecology, develop stewardship attitudes and behaviors toward the environment, and become positive role models for …

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Climate Change Effects And Water Vulnerability In The Molalla Pudding River Basin, Oregon, Usa, Susan Amelia Wherry Jan 2012

Climate Change Effects And Water Vulnerability In The Molalla Pudding River Basin, Oregon, Usa, Susan Amelia Wherry

Dissertations and Theses

Water management plans are typically developed using historical data records and historical return periods for extreme events, such as floods or droughts. Since these analyses of return periods typically assume a certain degree of stationarity (constant mean, standard deviation, distribution) in hydrologic variables, the potential future impacts of climate change are excluded. In developing water management plans, predicted changes to climate variables should be considered to evaluate the degree of non-stationarity that may exist in the future. In this way, regions most sensitive to climate change can be identified and managed appropriately. This study performed such a task by using …

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Late Pleistocene And Holocene Aged Glacial And Climatic Reconstructions In The Goat Rocks Wilderness, Washington, United States, Joshua Andrews Heard Jan 2012

Late Pleistocene And Holocene Aged Glacial And Climatic Reconstructions In The Goat Rocks Wilderness, Washington, United States, Joshua Andrews Heard

Dissertations and Theses

Eight glaciers, covering an area of 1.63 km2, reside on the northern and northeastern slopes of the Goat Rocks tallest peaks in the Cascades of central Washington. At least three glacial stands occurred downstream from these glaciers. Closest to modern glacier termini are Little Ice Age (LIA) moraines that were deposited between 1870 and 1899 AD, according to the lichenometric analysis. They are characterized by sharp, minimally eroded crests, little to no soil cover, and minimal vegetation cover. Glacier reconstructions indicate that LIA glaciers covered 8.29 km2, 76% more area than modern ice coverage. The average LIA equilibrium line altitude …

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Finding The Past In The Present: Modeling Prehistoric Occupation And Use Of The Powder River Basin, Wyoming, Catherine Anne Clark Jan 2012

Finding The Past In The Present: Modeling Prehistoric Occupation And Use Of The Powder River Basin, Wyoming, Catherine Anne Clark

Dissertations and Theses

In the Powder River Basin of Wyoming, our nation's interest in protecting its cultural heritage collides with the high demand for carbon fuels. "Clinker" deposits dot the basin. These distinctive buttes, created by the underground combustion of coal, are underlain by coal veins; they also provided the main lithic resources for prehistoric hunter-gatherers. These deposits signify both a likelihood of extractable carbon and high archaeological site density. Federal law requires that energy developers must identify culturally significant sites before mining can begin. The research presented here explains the need for and describes a statistical tool with the potential to predict …

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Scale Invariant Object Recognition Using Cortical Computational Models And A Robotic Platform, Danny Voils Jan 2012

Scale Invariant Object Recognition Using Cortical Computational Models And A Robotic Platform, Danny Voils

Dissertations and Theses

This paper proposes an end-to-end, scale invariant, visual object recognition system, composed of computational components that mimic the cortex in the brain. The system uses a two stage process. The first stage is a filter that extracts scale invariant features from the visual field. The second stage uses inference based spacio-temporal analysis of these features to identify objects in the visual field. The proposed model combines Numenta's Hierarchical Temporal Memory (HTM), with HMAX developed by MIT's Brain and Cognitive Science Department. While these two biologically inspired paradigms are based on what is known about the visual cortex, HTM and HMAX …

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Origin Of Surface Undulations At The Kamb Ice Stream Grounding Line, West Antarctica, Fiona Bronwyn Seifert Jan 2012

Origin Of Surface Undulations At The Kamb Ice Stream Grounding Line, West Antarctica, Fiona Bronwyn Seifert

Dissertations and Theses

The West Antarctic Ice Sheet is drained primarily by five major ice streams, which together control the volume of ice discharged into the ocean across the grounding line. The grounding line of Kamb Ice Stream (KIS) is unusual because the ice stream upstream of it is stagnant. Here, a set of surface features--shore-parallel, long wavelength, low amplitude undulations--found only at that grounding line are examined and found to be "pinch and swell" features formed by an instability in the viscous deformation of the ice. When a relatively competent layer is surrounded by lower strength materials, particular wavelength features within the …

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Growing Cities Depend On Ecosystem Services, David E. Ervin, Darrell Brown, Heejun Chang, Veronica Dujon, Elise F. Granek, Vivek Shandas, J. Alan Yeakley Jan 2012

Growing Cities Depend On Ecosystem Services, David E. Ervin, Darrell Brown, Heejun Chang, Veronica Dujon, Elise F. Granek, Vivek Shandas, J. Alan Yeakley

Geography Faculty Publications and Presentations

Many studies have documented the growing fragility of a majority of the globe's ecosystems. Policymakers and resource managers often frame such ecosystem challenges as primarily about protecting natural systems in rural areas. However, that conception misses a key part of the story: the rapid growth of urbanizing areas. Home to more than 50 percent of the world's human population for the first time in modern history, urbanizing regions concentrate pressure on ecosystem services, which are necessary to sustain healthy urban living conditions and vibrant commerce. This dramatic urbanization presents both challenges and opportunities for novel ecosystem services management. A transdisciplinary …

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