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Exponential Enhancement Of Field-Induced Pair Creation From The Bosonic Vacuum, R E. Wagner, M R. Ware, Q Su, Rainer Grobe 2010 Illinois State University

Exponential Enhancement Of Field-Induced Pair Creation From The Bosonic Vacuum, R E. Wagner, M R. Ware, Q Su, Rainer Grobe

Faculty publications – Physics

Using numerical solutions to quantum field theory, the creation of boson-antiboson pairs from the vacuum under a very strong localized external electric field is explored. The simulations reveal that the initial linear increase of the number of particles turns into an exponential growth. This self-amplification can be understood as the result of the interaction of the previously generated particles with the creation process. While the number of particles keeps increasing, the spatial shape of the (normalized) charge density of the created particles reaches a universal form that can be related to the bound states of the supercritical potential well. We ...


Creating A Game Plan For The Transition To A Sustainable U.S. Economy, Jeffrey Hollender, Robert Costanza, Gar Alperovitz, Christina Asquith, Bill Becker, Elliot Hoffman, Ellen Kahler, David Levine, L. Hunter Lovins, David Rapaport 2010 Portland State University

Creating A Game Plan For The Transition To A Sustainable U.S. Economy, Jeffrey Hollender, Robert Costanza, Gar Alperovitz, Christina Asquith, Bill Becker, Elliot Hoffman, Ellen Kahler, David Levine, L. Hunter Lovins, David Rapaport

Institute for Sustainable Solutions Publications and Presentations

The article focuses on the plan for the transition to a sustainable U.S. economy. It states that the economic crisis is viewed as an opportunity to reprioritize goals to emphasize sustainable design and healthy living over economic growth in the U.S. It discusses the five broad concepts and actions of the plan that includes cost estimation, getting off fossil fuels, and changing the ownership and purpose of the corporation.


Western Woburn Greenway Study, Jennifer H. Masters, Bryan C. Aldeghi, Eric C. Kells, Maureen C. Pollock, Rebekah Lynne Decourcey, Carol Waag, Youjin Kwon, Kathryn E. Ostermier, Patrick T. McGeough, Ryan Patrick Ball 2010 University of Massachusetts - Amherst

Western Woburn Greenway Study, Jennifer H. Masters, Bryan C. Aldeghi, Eric C. Kells, Maureen C. Pollock, Rebekah Lynne Decourcey, Carol Waag, Youjin Kwon, Kathryn E. Ostermier, Patrick T. Mcgeough, Ryan Patrick Ball

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

In spring 2010, the Department of Landscape Architecture and Regional Planning at the University of Massachusetts Amherst was asked to complete a landscape planning study, the “Western Woburn Greenway Study” for the City of Woburn, MA. The study was undertaken by a team of graduate students, supervised by Professor Jack Ahern. The goals of that study are as follows.

The City of Woburn currently has two large parcel groups of undeveloped land, Whispering Hill (the north focus area) and Winning/Shannon Farms (the south focus area) that are, or may become, available for acquisition (see “Scope of Project” below). The ...


Significance Of Water-Related Features On Mars, Eileen Marie Mcgowan 2010 University of Massachusetts Amherst

Significance Of Water-Related Features On Mars, Eileen Marie Mcgowan

Open Access Dissertations

The debate on whether water exists on Mars has been resolved by recent data from the Mars Phoenix Polar Lander. The lander found water ice just below the surface in the high northern latitudes of Mars. The questions to be answered now are: how much water was present in the past, how much water is currently present, what was the state the water in the past, and what is the current state of water on Mars. The morphology and spatial relationships are examined between three different landforms (pitted cones, giant polygons, and putative shorelines) considered to be the result of ...


A History And Test Of Planetary Weather Forecasting, Bruce Scofield 2010 University of Massachusetts Amherst

A History And Test Of Planetary Weather Forecasting, Bruce Scofield

Open Access Dissertations

A unique methodology for forecasting weather based on geocentric planetary alignments originated in ancient Mesopotamia. The method, called astrometeorology, was further developed by Greek, Arab, and Renaissance scientists including Ptolemy, Al-Kindi, Tycho Brahe and Joannes Kepler. A major 17th century effort to test the method in a Baconian fashion was made by John Goad. Building on the ideas of Kepler and Goad, I test an isolated component of the method, specifically a correlation between geocentric Sun-Saturn alignments and cold temperatures, using modern daily temperature data from New England, Central England, Prague and other locations. My hypothesis states there is a ...


Geometric And Combinatorial Aspects Of 1-Skeleta, Chris Ray McDaniel 2010 University of Massachusetts Amherst

Geometric And Combinatorial Aspects Of 1-Skeleta, Chris Ray Mcdaniel

Open Access Dissertations

In this thesis we investigate 1-skeleta and their associated cohomology rings. 1-skeleta arise from the 0- and 1-dimensional orbits of a certain class of manifold admitting a compact torus action and many questions that arise in the theory of 1-skeleta are rooted in the geometry and topology of these manifolds. The three main results of this work are: a lifting result for 1-skeleta (related to extending torus actions on manifolds), a classification result for certain 1-skeleta which have the Morse package (a property of 1-skeleta motivated by Morse theory for manifolds) and two constructions on 1-skeleta which we show preserve ...


A Study Of Three Artificial Neural Networks Models' Ability To Identify Emotions From Facial Images, Timothy Scott Hyde 2010 Columbus State University

A Study Of Three Artificial Neural Networks Models' Ability To Identify Emotions From Facial Images, Timothy Scott Hyde

Theses and Dissertations

Facial expressions conveying emotions are vital for human communication. They are also important in the studies of human interaction and behavioral studies. Recognition of emotions, using facial images, may provide a fast and practical approach that is noninvasive. Most previous studies of emotion recognition through facial images were based on the Facial Action Coding System (FACS). The FACS, which was developed by Ekman and Freisen in 1978, was created to identify different facial muscular actions. Previous artificial neural network-based approaches for classification of facial expressions focused on improving one particular neural network model for better accuracy. The purpose of this ...


Global Project Management: Pedagogy For Distributed Teams, Benjamin Kok Siew GAN, Randy WEINBERG, Selma Limam MANSAR 2010 Singapore Management University

Global Project Management: Pedagogy For Distributed Teams, Benjamin Kok Siew Gan, Randy Weinberg, Selma Limam Mansar

Research Collection School Of Information Systems

This paper reflects on pedagogy for teaching collaborative global projects across universities in different countries. Over a period of four years, students at three universities - one in the United States, one in Singapore and one in the Middle East - enrolled in a course called "Global Project Management". In this course, coordinated across locations, students experience a global project with distant team members. We describe the course experience and student perceptions of the requisite skills, collaboration tools and challenges bearing on effective global project work.


Efficient Unidirectional Proxy Re-Encryption, Sherman CHOW, Weng JIAN, Yanjiang YANG, Robert H. DENG 2010 New York University

Efficient Unidirectional Proxy Re-Encryption, Sherman Chow, Weng Jian, Yanjiang Yang, Robert H. Deng

Research Collection School Of Information Systems

Proxy re-encryption (PRE) allows a semi-trusted proxy to convert a ciphertext originally intended for Alice into one encrypting the same plaintext for Bob. The proxy only needs a re-encryption key given by Alice, and cannot learn anything about the plaintext encrypted. This adds flexibility in various applications, such as confidential email, digital right management and distributed storage. In this paper, we study unidirectional PRE, which the re-encryption key only enables delegation in one direction but not the opposite. In PKC 2009, Shao and Cao proposed a unidirectional PRE assuming the random oracle. However, we show that it is vulnerable to ...


Innovative Entrepreneurs Workbook, Arcot Desai NARASIMHALU 2010 Singapore Management University, Institute of Innovation and Entrepreneurship

Innovative Entrepreneurs Workbook, Arcot Desai Narasimhalu

Research Collection School Of Information Systems

The workbook provides a step by step approach to identifying innovation opportunities and the key aspects of Innovation development


The Global Development Of A Css-Based Service And Technology Market With A Focus On The Us, France, And China, Cameron Rolfe McQuale 2010 University of Pennsylvania

The Global Development Of A Css-Based Service And Technology Market With A Focus On The Us, France, And China, Cameron Rolfe Mcquale

Master of Environmental Studies Capstone Projects

No abstract provided.


Reality Check: Combining Survey And Market Data To Estimate The Importance Of Product Attributes, Elea M. Feit, Mark A. Beltramo, Fred M. Feinberg 2010 University of Pennsylvania

Reality Check: Combining Survey And Market Data To Estimate The Importance Of Product Attributes, Elea M. Feit, Mark A. Beltramo, Fred M. Feinberg

Marketing Papers

Discrete choice models estimated using hypothetical choices made in a survey setting (i.e., choice experiments) are widely used to estimate the importance of product attributes in order to make product design and marketing mix decisions. Choice experiments allow the researcher to estimate preferences for product features that do not yet exist in the market. However, parameters estimated from experimental data often show marked inconsistencies with those inferred from the market, reducing their usefulness in forecasting and decision making. We propose an approach for combining choice-based conjoint data with individual-level purchase data to produce estimates that are more consistent with ...


Quaternary Structure Of Chemoreceptors In Active Signaling Complexes Differs From Crystal Structure Of Isolated Fragments: Evidence From Solid-State Nmr, Daniel John Fowler 2010 University of Massachusetts Amherst

Quaternary Structure Of Chemoreceptors In Active Signaling Complexes Differs From Crystal Structure Of Isolated Fragments: Evidence From Solid-State Nmr, Daniel John Fowler

Open Access Dissertations

The receptor dimers that mediate bacterial chemotaxis form high-order signaling complexes with CheW and the kinase CheA. From the packing arrangement in two crystal structures of different receptor cytoplasmic fragments, two different models have been proposed for receptor signaling arrays: the trimers-of-dimers and hedgerow models. We identified an interdimer distance that differs substantially in the two models, labeled the atoms defining this distance through isotopic enrichment, and measured it with 13C-19F REDOR. This was done in two types of receptor samples: first, isolated bacterial membranes containing overexpressed, intact receptor, and second, soluble receptor fragments reconstituted into kinase-active signaling complexes. In ...


Whole-Body Strategies For Mobility And Manipulation, Patrick Deegan 2010 University of Massachusetts Amherst

Whole-Body Strategies For Mobility And Manipulation, Patrick Deegan

Open Access Dissertations

The robotics community has succeeded in creating remarkable machines and task-level programming tools, but arguably has failed to apply sophisticated autonomous machines to sophisticated tasks. One reason is that this combination leads to prohibitive complexity. Biological systems provide many examples of integrated systems that combine high-performance and flexibility, with logically-organized low-level control. Sophisticated organisms have evolved that depend on physical dexterity to thrive in a particular ecological niche while mitigating computational and behavioral complexity. This dissertation investigates the potential for a new kind of hybrid robotic design process. A design for performance that combines mechanical dexterity with low-level embedded firmware ...


Discovery Of Complex Regulatory Modules From Expression Genetics Data, Manjunatha Jagalur 2010 University of Massachusetts Amherst

Discovery Of Complex Regulatory Modules From Expression Genetics Data, Manjunatha Jagalur

Open Access Dissertations

Mapping of strongly inherited classical traits have been immensely helpful in understanding many important traits including diseases, yield and immunity. But some of these traits are too complex and are difficult to map. Taking into consideration gene expression, which mediates the genetic effects, can be helpful in understanding such traits. Together with genetic variation data such data-set is collectively known as expression genetics data. Presence of discrete and continuous variables, observed and latent variables, availability of partial causal information, and under-specfied nature of the data make expression genetics data computationally challenging, but potentially of great biological importance. In this dissertation ...


On The Design Of Methods To Estimate Network Characteristics, Bruno F. Ribeiro 2010 University of Massachusetts Amherst

On The Design Of Methods To Estimate Network Characteristics, Bruno F. Ribeiro

Open Access Dissertations

Social and computer networks permeate our lives. Large networks, such as the Internet, the World Wide Web (WWW), AND wireless smartphones, have indisputable economic and social importance. These networks have non-trivial topological features, i.e., features that do not occur in simple networks such as lattices or random networks. Estimating characteristics of these networks from incomplete (sampled) data is a challenging task. This thesis provides two frameworks within which common measurement tasks are analyzed and new, principled, measurement methods are designed. The first framework focuses on sampling directly observable network characteristics. This framework is applied to design a novel multidimensional ...


Generalized Emp And Nonlinear Schrodinger-Type Reformulations Of Some Scaler Field Cosmological Models, Jennie D'Ambroise 2010 University of Massachusetts Amherst

Generalized Emp And Nonlinear Schrodinger-Type Reformulations Of Some Scaler Field Cosmological Models, Jennie D'Ambroise

Open Access Dissertations

We show that Einstein’s gravitational field equations for the Friedmann- Robertson-Lemaître-Walker (FRLW) and for two conformal versions of the Bianchi I and Bianchi V perfect fluid scalar field cosmological models, can be equivalently reformulated in terms of a single equation of either generalized Ermakov-Milne- Pinney (EMP) or (non)linear Schrödinger (NLS) type. This work generalizes or presents an alternative to similar reformulations published by the authors who inspired this thesis: R. Hawkins, J. Lidsey, T. Christodoulakis, T. Grammenos, C. Helias, P. Kevrekidis, G. Papadopoulos and F.Williams. In particular we cast much of these authors’ works into a single ...


On The Frequency Of Finitely Anomalous Elliptic Curves, Penny Catherine Ridgdill 2010 University of Massachusetts Amherst

On The Frequency Of Finitely Anomalous Elliptic Curves, Penny Catherine Ridgdill

Open Access Dissertations

Given an elliptic curve E over Q, we can then consider E over the finite field Fp. If Np is the number of points on the curve over Fp, then we define ap(E) = p+1-Np. We say primes p for which ap(E) = 1 are anomalous. In this paper, we search for curves E so that this happens for only a finite number of primes. We call such curves finitely anomalous. This thesis deals with the frequency of their occurrence and finds several examples.


Optimal Control In Discrete Pest Control Models, Kathryn Dabbs 2010 University of Tennessee - Knoxville

Optimal Control In Discrete Pest Control Models, Kathryn Dabbs

University of Tennessee Honors Thesis Projects

No abstract provided.


Mad Gardens Compassion And Education: An Environmental Journal Of Literature, Art And Culture For Smith College, Rebecca Benson, Kratman Veronica 2010 Smith College

Mad Gardens Compassion And Education: An Environmental Journal Of Literature, Art And Culture For Smith College, Rebecca Benson, Kratman Veronica

Other Projects

In the last few years environmental issues have finally come to be seen as problems that address all aspects of society. From the air we breathe, to the water we drink, food we eat and places we go every decision we make has consequences in the environment and our environment effects those decisions. The idea for creating an interdisciplinary environmental journal stemmed out of this knowledge and from my academic career at Smith College. This paper will show the process Veronica Kratman and I took in creating Mad Gardens an interdisciplinary environmental literature, arts and culture journal and the finished ...


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