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University of Massachusetts Amherst

2012

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Full-Text Articles in Physical Sciences and Mathematics

Climate Change Adaptation Chapter: Marshfield, Massachusetts, Joshua H. Chase, Jonathan G. Cooper, Rory Elizabeth Fitzgerald, Filipe Antunes Lima, Sally R. Miller, Toni Marie Pignatelli Dec 2012

Climate Change Adaptation Chapter: Marshfield, Massachusetts, Joshua H. Chase, Jonathan G. Cooper, Rory Elizabeth Fitzgerald, Filipe Antunes Lima, Sally R. Miller, Toni Marie Pignatelli

Landscape Architecture & Regional Planning Studio and Student Research and Creative Activity

Climate change, understood as a statistically significant variation in the mean state of the climate or its variability, is the greatest environmental challenge of this generation (Intergovernmental Panel on Climate Change, 2001). Marshfield is already being affected by changes in the climate that will have a profound effect on the town’s economy, public health, coastal resources, natural features, water systems, and public and private infrastructure. Adaptation strategies have been widely recognized as playing an important role in improving a community’s ability to respond to climate stressors by resisting damage and recovering quickly.

Based on review of climate projections for the …


A Bayesian Model For Pooling Gene Expression Studies That Incorporates Co-Regulation Information, Erin Conlon, Bradley L. Postier, Barbara Methé, Kelly Nevin, Derek Lovley Jan 2012

A Bayesian Model For Pooling Gene Expression Studies That Incorporates Co-Regulation Information, Erin Conlon, Bradley L. Postier, Barbara Methé, Kelly Nevin, Derek Lovley

Microbiology Department Faculty Publication Series

Current Bayesian microarray models that pool multiple studies assume gene expression is independent of other genes. However, in prokaryotic organisms, genes are arranged in units that are co-regulated (called operons). Here, we introduce a new Bayesian model for pooling gene expression studies that incorporates operon information into the model. Our Bayesian model borrows information from other genes within the same operon to improve estimation of gene expression. The model produces the gene-specific posterior probability of differential expression, which is the basis for inference. We found in simulations and in biological studies that incorporating co-regulation information improves upon the independence model. …


Mapping “Diversity Of Participation” In Networked Media Environments, Martha Fuentes Bautista Jan 2012

Mapping “Diversity Of Participation” In Networked Media Environments, Martha Fuentes Bautista

National Center for Digital Government

In the United States the transition to an increasingly digital communication environment under pro-market policies has challenged traditional formulations of media diversity and localism regulation centered on content origination requirements and media ownership. Building on an overview of the participatory development and media policy literatures, this paper argues for a participatory community development approach to the redefinition of these public interest policies in networked scenarios. Asking who is participating in what, and for whose benefit, I propose a diversity matrix of various modalities of community participation in key public service functions of digital information organizations. The paper discusses …


The Role Of Structural Stormwater Best Management Practices, Impervious Surfaces And Natural Factors On Base Flow In Massachusetts, Kimberly B. Klosterman Jan 2012

The Role Of Structural Stormwater Best Management Practices, Impervious Surfaces And Natural Factors On Base Flow In Massachusetts, Kimberly B. Klosterman

Masters Theses 1911 - February 2014

This research conducted a GIS analysis of twenty-eight sub-watersheds in Massachusetts and considered five factors which the literature suggested influenced base flow. The literature suggested a positive relation between precipitation, forest cover and base flow and a negative relationship between impervious surfaces, soil drainage class, slope and base flow. A multiple regression analysis of the sub-watershed information confirmed the literature for two factors (soil drainage class and slope) and questioned it on three factors (impervious surfaces, precipitation, and forest cover). The resulting predictive equation indicated that imperviousness and precipitation were the most significant factors affecting base flow. The first derivative …


How Does Hydropeaking Alter The Hydrology Of A River Reach? A Combined Water Budget, Modeling, And Field Observation Study. Deerfield River, Massachusetts, Brian C. Yellen Jan 2012

How Does Hydropeaking Alter The Hydrology Of A River Reach? A Combined Water Budget, Modeling, And Field Observation Study. Deerfield River, Massachusetts, Brian C. Yellen

Masters Theses 1911 - February 2014

Hydroelectric releases on the Deerfield River in northwestern Massachusetts affect surface water-groundwater interactions there by daily reversing the head gradient between river and groundwater. Artificially elevated stage drives river water into the riparian aquifer. Water budget analysis indicates that roughly 10% of this bank-stored water is permanently lost from the river system in a 19.5 km reach, likely as a result of transpiration by bank vegetation.

Field observations as well as two-dimensional modeling results show that water losses are not uniform throughout the study reach. Riparian aquifer transmissivity in river sub-reaches largely determines the magnitude of surface water-groundwater exchange as …


Synthesis Of Monomers For New Conjugated Polymers, Kedar Girish Jadhav Jan 2012

Synthesis Of Monomers For New Conjugated Polymers, Kedar Girish Jadhav

Masters Theses 1911 - February 2014

ABSTRACT

SYNTHESIS OF MONOMERS FOR NEW CONJUGATED POLYMERS

This dissertation addresses the problem of synthesis of different monomers for donor and acceptor polymers in photovoltaic applications. In general, functionalization of conjugated polymers and understanding of molecular packing of electron donors and electron acceptors are very important to produce efficient solar cells. As a result, it is important to design and synthesize novel monomers which will require making new π-conjugated donors and acceptors polymers and understand the influence of these new polymers in bulk heterojunction to design polymer solar cells. In this study, two different monomers were synthesized. The first monomer …


Evolution Of Volatile Content Of The Parent Magma Of The 1875 Eruption Of Askja Volcano, Iceland, Heather A. Clark Jan 2012

Evolution Of Volatile Content Of The Parent Magma Of The 1875 Eruption Of Askja Volcano, Iceland, Heather A. Clark

Masters Theses 1911 - February 2014

The bulk of the eruption of Askja in north central Iceland on March 28-29 1875 consisted of a plinian eruption that lasted 6-7 hours, produced 0.2 km3 of ash and rhyolitic pumice, and created a surge and partially welded ash/pumice fall deposit that crops out on the shore of the modern caldera lake (Sparks et al. 1981). We evaluate the volatile budget of the magma during the eruption and focus on water concentration in glass fragments and shards, glass adjacent to crystals, and melt inclusions (MIs). Sparks et al. (1981) estimated the gas exit velocity at the vent was …


Driver Dynamics And The Longitudinal Control Model, Gabriel G. Leiner Jan 2012

Driver Dynamics And The Longitudinal Control Model, Gabriel G. Leiner

Masters Theses 1911 - February 2014

Driver psychology is one of the most difficult phenomena to model in the realm of traffic flow theory because mathematics often cannot capture the human factors involved with driving a car. Over the past several decades, many models have attempted to model driver aggressiveness with varied results. The recently proposed Longitudinal Control Model (LCM) makes such an attempt, and this paper offers evidence of the LCM's usefulness in modeling road dynamics by analyzing deceleration rates that are commonly associated with various levels of aggression displayed by drivers. The paper is roughly divided into three sections, one outlining the LCM's ability …


Diving Behavior And Identification Of Sex Of Breeding Atlantic Puffins (Fratercula Arctica), And Nest-Site Characteristics Of Alcids On Petit Manan Island, Maine, Sarah M. Spencer Jan 2012

Diving Behavior And Identification Of Sex Of Breeding Atlantic Puffins (Fratercula Arctica), And Nest-Site Characteristics Of Alcids On Petit Manan Island, Maine, Sarah M. Spencer

Masters Theses 1911 - February 2014

During 2008 – 2009, we quantified foraging behavior of adult Atlantic puffins (Fratercula arctica) by deploying time-depth recorders (TDRs) on 18 adults and collected morphological measurements from 40 adults nesting on Petit Manan Island, Maine. Dive data were successfully retrieved from 5 birds foraging for 14 days in 2008, and 8 birds foraging for 18 days in 2009. Pooling across all birds, a total of 8,097 dives were recorded, with peaks in activity during 0400-0800 and 1600-2000, and no diving between 2100 and 0400. Mean (± SD) dives/bird/day was 276.4 (± 84.7), with dives grouped into bouts lasting …


A Paleoclimate Modeling Experiment To Calculate The Soil Carbon Respiration Flux For The Paleocene-Eocene Thermal Maximum, David M. Tracy Jan 2012

A Paleoclimate Modeling Experiment To Calculate The Soil Carbon Respiration Flux For The Paleocene-Eocene Thermal Maximum, David M. Tracy

Masters Theses 1911 - February 2014

The Paleocene-Eocene Thermal Maximum (PETM) (55 million years ago) stands as the largest in a series of extreme warming (hyperthermal) climatic events, which are analogous to the modern day increase in greenhouse gas concentrations. Orbitally triggered (Lourens et al., 2005, Galeotti et al., 2010), the PETM is marked by a large (-3‰) carbon isotope excursion (CIE). Hypothesized to be methane driven, Zeebe et al., (2009) noted that a methane based release would only account for 3.5°C of warming. An isotopically heavier carbon, such as that of soil and C3 plants, has the potential to account for the …


A Combined Quadtree/Delaunay Method For 2d Mesh Generation, Simon Tang Jan 2012

A Combined Quadtree/Delaunay Method For 2d Mesh Generation, Simon Tang

Masters Theses 1911 - February 2014

Unstructured simplicial mesh is an integral and critical part of many computational electromagnetics methods (CEM) such as the finite element method (FEM) and the boundary element method (BEM). Mesh quality and robustness have direct impact on the success of these CEM methods.

A combined quadtree/Delunay 2D mesh generator, based on the early work of Schroeder (1991, PhD), is presented. The method produces a triangulation that approximates the original geometric model but is also topologically consistent. The key advantages of the method are: (a) its robustness, (b) ability to create a-priori graded meshes, and (c) its guaranteed mesh quality.

The method …


Holocene Climate And Environmental Changes: Disentangling Natural And Anthropogenic Signals In The Sedimentary Record Of Lake Lilandsvatnet (Nw Norway), Robert M. D'Anjou Jan 2012

Holocene Climate And Environmental Changes: Disentangling Natural And Anthropogenic Signals In The Sedimentary Record Of Lake Lilandsvatnet (Nw Norway), Robert M. D'Anjou

Masters Theses 1911 - February 2014

This thesis presents a multi-proxy paleoenvironmental reconstruction from the sedimentary archives of Lilandsvatnet, a small arctic lake on Vestvågøy, in the Lofoten Islands, Norway. Lofoten has a rich history of human settlements existing throughout the Holocene. The catchment of Lilandsvatnet was the location of a prominent Viking chieftain farm that existed throughout the Iron Age, and the sedimentary archive contains a strong signal of prehistoric and historic human settlements and land-use practices. Paleoenvironmental reconstructions in this thesis show evidence for Holocene environmental variability in response to both natural and anthropogenic forcing. Cryptotephra deposits from Icelandic eruptions further contrain sediment chronology …


Reformulation Of The Muffin-Tin Problem In Electronic Structure Calculations Within The Feast Framework, Alan R. Levin Jan 2012

Reformulation Of The Muffin-Tin Problem In Electronic Structure Calculations Within The Feast Framework, Alan R. Levin

Masters Theses 1911 - February 2014

This thesis describes an accurate and scalable computational method designed to perform nanoelectronic structure calculations. Built around the FEAST framework, this method directly addresses the nonlinear eigenvalue problem. The new approach allows us to bypass traditional approximation techniques typically used for first-principle calculations. As a result, this method is able to take advantage of standard muffin-tin type domain decomposition techniques without being hindered by their perceived limitations. In addition to increased accuracy, this method also has the potential to take advantage of parallel processing for increased scalability.

The Introduction presents the motivation behind the proposed method and gives an overview …


Spatial And Temporal Correlations Of Freeway Link Speeds: An Empirical Study, Piotr J. Rachtan Jan 2012

Spatial And Temporal Correlations Of Freeway Link Speeds: An Empirical Study, Piotr J. Rachtan

Masters Theses 1911 - February 2014

Congestion on roadways and high level of uncertainty of traffic conditions are major considerations for trip planning. The purpose of this research is to investigate the characteristics and patterns of spatial and temporal correlations and also to detect other variables that affect correlation in a freeway setting. 5-minute speed aggregates from the Performance Measurement System (PeMS) database are obtained for two directions of an urban freeway – I-10 between Santa Monica and Los Angeles, California. Observations are for all non-holiday weekdays between January 1st and June 30th, 2010. Other variables include traffic flow, ramp locations, number of lanes and the …


Large Scale Image Retrieval From Books, Mao Zhao Jan 2012

Large Scale Image Retrieval From Books, Mao Zhao

Masters Theses 1911 - February 2014

Search engines play a very important role in daily life. As multimedia product becomes more and more popular, people have developed search engines for images and videos. In the first part of this thesis, I propose a prototype of a book image search engine. I discuss tag representation for the book images, as well as the way to apply the probabilistic model to generate image tags. Then I propose the random walk refinement method using tag similarity graph. The image search system is built on the Galago search engine developed in UMASS CIIR lab.

Consider the large amount of data …


Characterization Of Damage Zones Associated With Laboratory Produced Natural Hydraulic Fractures, Erin Bradley Jan 2012

Characterization Of Damage Zones Associated With Laboratory Produced Natural Hydraulic Fractures, Erin Bradley

Masters Theses 1911 - February 2014

Both joint sets and fault-related fractures serve as important conduits for fluid flow. In the former case, they can strongly influence both permeability and permeability anisotropy, with implications for production of water, hydrocarbons and contaminant transport. The latter can affect issues of fluid flow, such as whether a given fault seals or leaks, and fault mechanics. These fractures are commonly interpreted as Natural Hydraulic Fractures (NHFs), i.e., mode 1 fractures produced when pore fluid pressure exceeds the tensile strength of the rock. Various mathematical models have been a rich source of hypotheses to explain the formation and propagation of NHFs, …


Fractures Of The Dammam Dome Carbonate Outcrops: Their Characterization, Development, And Implications For Subsurface Reservoirs, Mohammed M. Al-Fahmi Jan 2012

Fractures Of The Dammam Dome Carbonate Outcrops: Their Characterization, Development, And Implications For Subsurface Reservoirs, Mohammed M. Al-Fahmi

Masters Theses 1911 - February 2014

The exposed Tertiary carbonates of the Dammam Dome present an opportunity to study fractures in outcrops within the oil-producing region of Eastern Saudi Arabia. The study focuses on: 1) the characterization of fractures, 2) interpretation of their fracturing mechanism, and 3) the implications for the deep carbonate reservoirs of the Dammam Dome. The characterization of the outcrop fractures is integrated with structural analysis of the near-surface horizons mapped from reflection seismic and well data. Fractures are observed within all exposed carbonate units, but predominantly within the widely exposed Middle Rus unit. The fractures are opening-mode, bed-bound joints that form orthogonal …


Fy 2012 Umass Amherst Waste Management Report, Ezra Small Jan 2012

Fy 2012 Umass Amherst Waste Management Report, Ezra Small

Campus Data

Each year the Office of Waste Management publishes this report which totals recycling and refuse data for the campus.


Fy 2012 Umass Amherst Electricity Data By Building, Ezra Small Jan 2012

Fy 2012 Umass Amherst Electricity Data By Building, Ezra Small

Campus Data

Each year, UMass Amherst Utilities publishes this spreadsheet which has the monthly and annual building energy consumption of each metered building on campus. Cost data and production vs. purchased electricity data are also provided.


Fy 2012 Umass Amherst Water & Steam Data By Building, Ezra Small Jan 2012

Fy 2012 Umass Amherst Water & Steam Data By Building, Ezra Small

Campus Data

Each year, UMass Amherst Utilities publishes this spreadsheet which has the monthly and annual building water and steam consumption of each metered building on campus.


Childhood Body Mass Index Trajectories: Modeling, Characterizing, Pairwise Correlations And Socio-Demographic Predictors Of Trajectory Characteristics, Xiaozhong Wen, Ken Kleinman, Matthew W. Gillman, Sherly L. Rifas-Shiman, Elsie M. Taveras Jan 2012

Childhood Body Mass Index Trajectories: Modeling, Characterizing, Pairwise Correlations And Socio-Demographic Predictors Of Trajectory Characteristics, Xiaozhong Wen, Ken Kleinman, Matthew W. Gillman, Sherly L. Rifas-Shiman, Elsie M. Taveras

Public Health Department Faculty Publication Series

BACKGROUND:

Modeling childhood body mass index (BMI) trajectories, versus estimating change in BMI between specific ages, may improve prediction of later body-size-related outcomes. Prior studies of BMI trajectories are limited by restricted age periods and insufficient use of trajectory information.

METHODS:

Among 3,289 children seen at 81,550 pediatric well-child visits from infancy to 18 years between 1980 and 2008, we fit individual BMI trajectories using mixed effect models with fractional polynomial functions. From each child's fitted trajectory, we estimated age and BMI at infancy peak and adiposity rebound, and velocity and area under curve between 1 week, infancy peak, adiposity …


Estimation Of Newborn Risk For Child Or Adolescent Obesity:Lessons From Longitudinal Birth Cohorts, Anita Morandi, David Meyre, Stephane Lobbens, Ken Kleinman, Marika Kaakinen, Sheryl L. Rifas-Shiman, Vincent Vatin, Stefan Gaget, Anneli Pouta, Anna-Liisa Hartikainen, Jaana Laitinen, Matthew W. Gillman, Marjo-Riitta Jarvelin, Philippe Froguel Jan 2012

Estimation Of Newborn Risk For Child Or Adolescent Obesity:Lessons From Longitudinal Birth Cohorts, Anita Morandi, David Meyre, Stephane Lobbens, Ken Kleinman, Marika Kaakinen, Sheryl L. Rifas-Shiman, Vincent Vatin, Stefan Gaget, Anneli Pouta, Anna-Liisa Hartikainen, Jaana Laitinen, Matthew W. Gillman, Marjo-Riitta Jarvelin, Philippe Froguel

Public Health Department Faculty Publication Series

OBJECTIVES:

Prevention of obesity should start as early as possible after birth. We aimed to build clinically useful equations estimating the risk of later obesity in newborns, as a first step towards focused early prevention against the global obesity epidemic.

METHODS:

We analyzed the lifetime Northern Finland Birth Cohort 1986 (NFBC1986) (N = 4,032) to draw predictive equations for childhood and adolescent obesity from traditional risk factors (parental BMI, birth weight, maternal gestational weight gain, behaviour and social indicators), and a genetic score built from 39 BMI/obesity-associated polymorphisms. We performed validation analyses in a retrospective cohort of 1,503 Italian children …


Department Of Physics Newsletter: Spring 2012, Dan Candela Jan 2012

Department Of Physics Newsletter: Spring 2012, Dan Candela

Physics Newsletters

No abstract provided.


Wind Power, Susn Reyes Jan 2012

Wind Power, Susn Reyes

Science and Engineering Saturday Seminars

No abstract provided.


Improving The Accuracy And Precision Of An Arsenic Field Test Kit: Increased Reaction Time And Digital Image Analysis, James Kearns, Julian Tyson Jan 2012

Improving The Accuracy And Precision Of An Arsenic Field Test Kit: Increased Reaction Time And Digital Image Analysis, James Kearns, Julian Tyson

Chemistry Department Faculty Publication Series

No abstract provided.


Will Extreme Climatic Events Facilitate Biological Invasions?, Jeffrey M. Diez, Carla M. D'Antonio, Jeffrey S. Dukes, Edwin D. Grosholz, Julian D. Olden, Cascade J B Sorte, Dana M. Blumenthal, Bethany Bradley, Regan Early, Ines Ibanez, Sierra J. Jones, Joshua J. Lawler, Luke P. Miller Jan 2012

Will Extreme Climatic Events Facilitate Biological Invasions?, Jeffrey M. Diez, Carla M. D'Antonio, Jeffrey S. Dukes, Edwin D. Grosholz, Julian D. Olden, Cascade J B Sorte, Dana M. Blumenthal, Bethany Bradley, Regan Early, Ines Ibanez, Sierra J. Jones, Joshua J. Lawler, Luke P. Miller

Environmental Conservation Faculty Publication Series

Extreme climatic events (ECEs) – such as unusual heat waves, hurricanes, floods, and droughts – can dramatically affect ecological and evolutionary processes, and these events are projected to become more frequent and more intense with ongoing climate change. However, the implications of ECEs for biological invasions remain poorly understood. Using concepts and empirical evidence from invasion ecology, we identify mechanisms by which ECEs may influence the invasion process, from initial introduction through establishment and spread. We summarize how ECEs can enhance invasions by promoting the transport of propagules into new regions, by decreasing the resistance of native communities to establishment, …


The Invasive Grass-Fire Cycle In The U.S. Great Basin, Jennifer K. Balch, Marnie K. Carroll, Bethany A. Bradley Jan 2012

The Invasive Grass-Fire Cycle In The U.S. Great Basin, Jennifer K. Balch, Marnie K. Carroll, Bethany A. Bradley

Environmental Conservation Faculty Publication Series

No abstract provided.


Depth Camera Based Indoor Mobile Robot Localization And Navigation, Joydeep Biswas, Manuela M. Veloso Jan 2012

Depth Camera Based Indoor Mobile Robot Localization And Navigation, Joydeep Biswas, Manuela M. Veloso

Computer Science Department Faculty Publication Series

The sheer volume of data generated by depth cameras provides a challenge to process in real time, in particular when used for indoor mobile robot localization and navigation. We introduce the Fast Sampling Plane Filtering (FSPF) algorithm to reduce the volume of the 3D point cloud by sampling points from the depth image, and classifying local grouped sets of points as belonging to planes in 3D (the “plane filtered” points) or points that do not correspond to planes within a specified error margin (the “outlier” points). We then introduce a localization algorithm based on an observation model that down-projects the …


Planar Polygon Extraction And Merging From Depth Images, Joydeep Biswas, Manuela M. Veloso Jan 2012

Planar Polygon Extraction And Merging From Depth Images, Joydeep Biswas, Manuela M. Veloso

Computer Science Department Faculty Publication Series

— There has been considerable interest recently in building 3D maps of environments using inexpensive depth cameras like the Microsoft Kinect sensor. We exploit the fact that typical indoor scenes have an abundance of planar features by modeling environments as sets of plane polygons. To this end, we build upon the Fast Sampling Plane Filtering (FSPF) algorithm that extracts points belonging to local neighborhoods of planes from depth images, even in the presence of clutter. We introduce an algorithm that uses the FSPF-generated plane filtered point clouds to generate convex polygons from individual observed depth images. We then contribute an …