Physical Sciences and Mathematics Commons^™

Particulate And Water-Soluble Carbon Measured In Recent Snow At Summit, Greenland, Gayle S.W. Hagler, M Bergin, Eugene A. Smith, Jack E. Dibb, Casey Anderson, Eric J. Steig

Earth Sciences

Water-soluble organic carbon (WSOC), waterinsoluble particulate organic carbon (WIOC), and particulate elemental carbon (EC) were measured simultaneously for the first time on the Greenland Ice Sheet in surface snow and in a 3-meter snow pit. Snow pit concentrations reveal that, on average, WSOC makes up the majority (89%) of carbonaceous species, followed by WIOC (10%) and EC (1%). The enhancement of OC relative to EC (ratio 99:1) in Greenland snow suggests that, along with atmospheric particulate matter, gaseous organics contribute to snow-phase OC. Comparison of summer surface snow concentrations in 2006 with past summer snow pit layers (2002 – 2005) …

Bubbling The False Vacuum Away, M. Gleiser, B. Rogers, J. Thorarinson

Dartmouth Scholarship

We investigate the role of nonperturbative, bubble-like inhomogeneities on the decay rate of false- vacuum states in two and three-dimensional scalar field theories. The inhomogeneities are induced by setting up large-amplitude oscillations of the field about the false vacuum as, for example, after a rapid quench or in certain models of cosmological inflation. We show that, for a wide range of parameters, the presence of large-amplitude bubble-like inhomogeneities greatly accelerates the de- cay rate, changing it from the well-known exponential suppression of homogeneous nucleation to a power-law suppression. It is argued that this fast, power-law vacuum decay – known as …

Application Packaging Tracking System, Cormac Quillinan

Regis University Student Publications (comprehensive collection)

In the business world it is very difficult to manage and track user application installations and licensing. The primary problem with this area is currently there is no single solution that encapsulates the entire process. The current commercially available tracking systems, such as SMS, DevTrack and Installshield Tracking system, do not provide a complete solution. These products provide partial solutions. However, they do not address the entire problem. In this thesis we proposed an Application Packaging Tracking System. This system tracks application installations throughout the entire process, from submission to deployment.

Environmental Kuznets Curve: Some Econometric Analyses., Soumyananda Dinda Dr.

Doctoral Theses

This dissertation explores some issues of environmental economics and development. A concept crystallizing in the development and environmental economics literature is the notion that socioeconomic and environmental measures follow predictable paths associated with growing per capita income. In this context, the nature of relationship between economic development and environmental quality has become the focus of increasing attention. The issue of whether environmental degradation increases monotonically, decreases monotonically, or at first increases and then declines along a country’s development path, has critical implications for policy. Whilst development through industrialization brings higher incomes and well-being, this seems to act as a magnifier …

Displacement Detection With A Vibrating Rf Superconducting Interference Device: Beating The Standard Linear Limit, Eyal Buks, Stav Zaitsev, Eran Segev, Baleegh Abdo, M. P. Blencowe

Dartmouth Scholarship

We study a configuration for displacement detection consisting of a nanomechanical resonator coupled to both a radio frequency superconducting interference device and to a superconducting stripline resonator. We employ an adiabatic approximation and rotating wave approximation and calculate the displacement sensitivity. We study the performance of such a displacement detector when the stripline resonator is driven into a region of nonlinear oscillations. In this region the system exhibits noise squeezing in the output signal when homodyne detection is employed for readout. We show that displacement sensitivity of the device in this region may exceed the upper bound imposed upon the …

Antarctica, The Southern Ocean, And Climate Evolution: Insights From Drilling, Coring, And Geophysical Surveys, Timothy R. Naish, Ross Powell

ANDRILL Research and Publications

1.P2.A-1: The diatom record of the ANDRILL – McMurdo Ice Shelf project drillcore
Reed Scherer, Diane Winter, Charlotte Sjunneskog, and Paola Maffioli4

1.P2.A-2: Preliminary ⁴⁰Ar/³⁹Ar results from the AND-1B core
Jake I. Ross, William C. McIntosh, and Nelia W. Dunbar

1.P2.A-3: Preliminary chronostratigraphy for the upper 700 m (upper Miocene–Pleistocene) of the AND-1B drillcore recovered from beneath the McMurdo Ice Shelf, Antarctica
Gary S. Wilson, Richard H. Levy, Greg Browne, Fabio Florindo, Stuart A. Henrys, Ian Graham, William C. McIntosh, R. M. McKay, T. R. Naish, Christian Ohneiser, Ross D. Powell, Jake I. Ross, Leonardo Sagnotti, Reed …

Time-Dependent Performance Comparison Of Stochastic Optimization Algorithms, David Shilane, Jarno Martikainen, Seppo Ovaska

U.C. Berkeley Division of Biostatistics Working Paper Series

This paper proposes a statistical methodology for comparing the performance of stochastic optimization algorithms that iteratively generate candidate optima. The fundamental data structure of the results of these algorithms is a time series. Algorithmic differences may be assessed through a procedure of statistical sampling and multiple hypothesis testing of time series data. Shilane et al. propose a general framework for performance comparison of stochastic optimization algorithms that result in a single candidate optimum. This project seeks to extend this framework to assess performance in time series data structures. The proposed methodology analyzes empirical data to determine the generation intervals in …

Comparing Trends In Cancer Rates Across Overlapping Regions, Yi Li, Ram C. Tiwari

Harvard University Biostatistics Working Paper Series

No abstract provided.

Impact Of Multiscale Dynamical Processes And Mixing On The Chemical Composition Of The Upper Troposphere And Lower Stratosphere During The Intercontinental Chemical Transport Experiment–North America, T D. Fairlie, Melody A. Avery, R B. Pierce, J Al-Saadi, Jack E. Dibb, G W. Sachse

Earth Sciences

We use high-frequency in situ observations made from the DC8 to examine fine-scale tracer structure and correlations observed in the upper troposphere and lower stratosphere during INTEX-NA. Two flights of the NASA DC-8 are compared and contrasted. Chemical data from the DC-8 flight on 18 July show evidence for interleaving and mixing of polluted and stratospheric air masses in the vicinity of the subtropical jet in the upper troposphere, while on 2 August the DC-8 flew through a polluted upper troposphere and a lowermost stratosphere that showed evidence of an intrusion of polluted air. We compare data from both flights …

New Higher Order Rotation Spreading Matrix For Bsofdm, I. S. Raad, Xiaojing Huang, R. Raad

Faculty of Informatics - Papers (Archive)

Previously a new matrix called the Rotation spreading matrix was proposed for Block Spread OFDM which had advantages over other well known spreading matrices such as the Hadamard in frequency selective channels such the UWB channels. Then a new paper discussed a method to expand this Rotation spreading matrix into higher order allowing the system BSOFDM to achieve higher order matrices which still showed excellent orthogonal properties which can be used in these frequency selective channels. This work is continued on the Rotation spreading matrix and this paper presents another method to expand the Rotation spreading matrix based on Complete …

Complementary Channel Estimation And Synchronization For Ofdm, Darryn Lowe, Xiaojing Huang

Faculty of Informatics - Papers (Archive)

In this paper, we present a new type of packet preamble for orthogonal frequency division multiplexing (OFDM) systems that is based on a complementary sequence pair. It is shown how this approach permits a receiver to dynamically choose between frequency-domain equalization (FDE) and timedomain equalization (TDE). With FDE offering a low-complexity zero-forcing (ZF) equalization and TDE facilitating easy minimum mean square error (MMSE) estimation, it is concluded that a spectrally-flattened complementary sequence pair offers an outstanding combination of flexibility and performance.

Optimal Adaptive Hyperbolic Companding For Ofdm, Darryn Lowe, Xiaojing Huang

Faculty of Informatics - Papers (Archive)

In this paper, we derive and analyze a companding algorithm based on the hyperbolic tangent and inverse hyperbolic tangent functions for use in orthogonal frequency division multiplexing (OFDM) transceivers. Probability density functions (PDFs) that approximate the transmitted and received OFDM signals in the presence of additive white Gaussian noise (AWGN) are derived and used to analyze the degree of companding relative to the signal-to-noise ratio (SNR) and clipping level. A set of optimal companding linearity coefficients for the multiband OFDM (MB-OFDM) ultra-wideband (UWB) standard are presented.

A Study Of Different Angles For Higher Order Rotation Spreading Matrix For Bsofdm In Uwb Channels, Ibrahim S. Raad, Xiaojing Huang, R. Raad

Faculty of Informatics - Papers (Archive)

This paper presents a study into different angles for higher order Rotation spreading matrix developed for BSOFDM. It was shown previously that for block size M = 2 that the angle α = π/3 achieved the best result in terms of BER in UWB channels. It was discovered that this was no longer the case when the higher order Rotation spreading matrix was used for larger M sized blocks and that other angles produced better results which proves that the Rotation spreading matrix advantage over existing spreading matrices such as the Hadamard is its flexibility to be adapted to different …

Scaling Behavior Of The Exchange-Bias Training Effect, Christian Binek, Srinivas Polisetty, Sarbeswar Sahoo

Christian Binek Publications

The dependence of the exchange-bias training effect on temperature and ferromagnetic film thickness is studied in detail and scaling behavior of the data is presented. Thickness-dependent exchange bias and its training are measured using the magneto-optical Kerr effect. A focused laser beam is scanned across a Co wedge probing local hysteresis loops of the Co film which is pinned by an antiferromagnetic CoO layer of uniform thickness. A phenomenological theory is best fitted to the exchange-bias training data resembling the evolution of the exchange-bias field on subsequently cycled hysteresis loops. Best fits are done for various temperatures and Co thicknesses. …

A Service - Oriented Approach To Onshore Gas Transmission Pipeline Construction, L. Dunn, P. Gibson

Faculty of Informatics - Papers (Archive)

This research investigates whether a traditional manufacturing planning and control strategy would make Onshore Gas Transmission Pipeline Construction more competitive and if so, design the strategy. An in-depth case study of Gas Transmission Pipeline Construction was carried out, along with an extensive literature review. The current pipeline construction process was analyzed from a strategic management perspective. From this perspective, it was found that the traditional 'make and sell' attitude of manufacturers has now almost entirely given way to a customer oriented 'sense and respond' service philosophy. This is compounded by the needs for waste avoidance, cost efficiency and service to …

Dynamical Modelling Of Luminous And Dark Matter In 17 Coma Early-Type Galaxies, J. Thomas, R. O. Saglia, R. Bender, D. Thomas, J K. Gebhardt, J. Magorrian, E. M. Corsini, G. Wegner

Dartmouth Scholarship

Dynamical models for 17 early‐type galaxies in the Coma cluster are presented. The galaxy sample consists of flattened, rotating as well as non‐rotating early‐types including cD and S0 galaxies with luminosities between M_B=−18.79 and −22.56. Kinematical long‐slit observations cover at least the major‐axis and minor‐axis and extend to 1–4r_eff. Axisymmetric Schwarzschild models are used to derive stellar mass‐to‐light ratios and dark halo parameters. In every galaxy, the best fit with dark matter matches the data better than the best fit without. The statistical significance is over 95 per cent for eight galaxies, around 90 per …

Faster Algorithms For Stable Allocation Problems, Siddharth Munshi

All Theses

We consider a high-multiplicity generalization of the classical stable matching problem known as the stable allocation problem, introduced by Baiou and Balinski in 2002. By leveraging new structural properties and sophisticated data structures, we show how to solve this problem in O(mlog n) time on an bipartite instance with n nodes and m edges, improving the best known running time of O(mn). Our approach simplifies the algorithmic landscape for this problem by providing a common generalization of two different approaches from the literature -- the classical Gale-Shapley algorithm, and a recent algorithm of Baiou and Balinski. Building on this algorithm, …

Comparison Of Thermoelectric Properties Of Arc-Melted And Hot-Pressed Half-Heuslers, Brad Edwards

All Theses

Relatively low thermal conductivity and great electrical properties in combination with wide tuning parameters through doping make half-Heuslers high potential thermoelectric materials. In this study we plan to investigate the effects of hot-pressing and arc-melting on the thermoelectric properties of ZrNiSn_0.975Sb_0.025, and Hf_0.75Zr_0.25NiSn_0.975Sb_0.025 samples. Also, the effects of electron and phonon scattering due to the insertion of small 50 nm particles within the sample were investigated in ZrNiSn_0.975Sb_0.025 +4% Al₂O₃ and Hf_0.75Zr_0.25NiSn_0.975Sb_0.025 +4% Al₂O …

Home Range And Habitat Use Of Feral Hogs (Sus Scrofa) In Congaree National Park, Bradford Friebel

All Theses

ABSTRACT One of the most destructive exotic wildlife species in the southeastern U.S. is the feral hog (Sus scrofa). To learn more about feral hog movement patterns and habitat use, hogs were radio-collared and tracked from April 2005 to November 2006 in Congaree National Park (CNP). Seven male and nine female hogs were monitored and their home ranges averaged 218.2 ± 42.9 ha and 194.1 ± 31.0 ha, respectively. These home ranges proved relatively small when compared to results from other analyses of home range size in feral hogs, and suggest an abundant resource base in CNP. Habitat use was …

The Thermoelectric Properties Investigation Of Ir3Ge7 Typed Representatives, Huqin Zhang

All Theses

Energy conversion is employed to power generation utilizing the Seebeck effect or cooling utilizing the Peltier effect. Herein, we study several Ir₃Ge₇ typed semiconductor materials for potential thermoelectric energy conversion. Mo₃Sb₇, crystallizing in Ir₃Ge₇ type, can be rendered semiconducting by a partial Sb-Te substitution without noticeable structure changes, resulting in Mo₃Sb₅Te₂ with 55 valence electrons per formula unit. Meanwhile, large cubic voids in the Mo₃Sb₅Te₂ crystal structure provide the possibility of filling the voids with small cations to decrease the …

Comparison Between Steady State And Laser Flash Techniques, Justine Andrews

All Theses

Thermoelectrics is a promising avenue of energy conservation. A material is deemed a good thermoelectric material when it portrays certain material characteristics. These characteristics include a high thermopower and electrical conductivity and a low thermal conductivity. This thesis focuses on the methods of measuring a material's thermal conductivity.
The steady state method is a measurement technique used in the low temperature thermal conductivity measurements. This technique assures that the system and sample are at equilibrium before a measurement point is taken. As a result the measurements are both precise and accurate.
The laser flash technique measures a sample's thermal conductivity …

Low Energy Scattering With A Nontrivial Pion, Joseph Schechter, Amir H. Fariborz, Renata Jora

Physics - All Scholarship

An earlier calculation in a generalized linear sigma model showed that the well-known current algebra formula for low energy pion pion scattering held even though the massless Nambu Goldstone pion contained a small admixture of a two-quark two-antiquark field. Here we turn on the pion mass and note that the current algebra formula no longer holds exactly. We discuss this small deviation and also study the effects of an SU(3) symmetric quark mass type term on the masses and mixings of the eight SU(3) multiplets in the model. We calculate the s wave scattering lengths, including the beyond current algebra …

Sea Ice Feedback And Cenozoic Evolution Of Antarctic Climate And Ice Sheets, Robert M. Deconto, David Pollard, David Harwood

Robert M DeConto

The extent and thickness of Antarctic sea ice have important climatic effects on radiation balance, energy transfer between the atmosphere and ocean, and moisture availability. This paper explores the role of sea ice and related feedbacks in the Cenozoic evolution of Antarctic climate and ice sheets, using a numerical climate model with explicit, dynamical representations of sea ice and continental ice sheets. In a scenario of decreasing Cenozoic greenhouse gas concentrations, our model initiates continental glaciation before any significant sea ice forms around the continent. Once variable ice sheets are established, seasonal sea ice distribution is highly sensitive to orbital …

Automorphic Decompositions Of Graphs, Robert Beeler

All Dissertations

Let G and H be graphs. A G-decomposition D of a graph H is a partition of the edge set of H such that the subgraph induced by the edges in each part of the partition is isomorphic to G. It is well known that a graceful labelling (or more generally a rho-valuation) of a graph G induces a cyclic G-decomposition of a complete graph. We will extend these notions to that of a general valuation in a cyclic group. Such valuations yield decompositions of circulant graphs. We will show that every graph has a valuation and hence is a …

Synthesis, Characterization, And Cyclopolymerization Of A Functional Non-Symmetric Divinyl Monomer, Bekir Dizman, Lon J. Mathias

Faculty Publications

A non-symmetric divinyl monomer with terminal carboxylic acid functionality was readily synthesized from the reaction of ethyl α-hydroxymethylacrylate (EHMA) with maleic anhydride. The new monomer (EHMA–MA) was homopolymerized in both bulk and ethyl acetate using AIBN as an initiator to give cyclopolymers. The synthesis of the monomer and cyclopolymers were followed by ¹³C NMR, ¹H NMR, and FTIR. ¹H NMR was also utilized to obtain the degree of cyclization of the polymers, which were found to be 95% or higher in all cases. The molecular weights of the cyclopolymers were around 40–60,000 g/mol as estimated by SEC. …

The Power Of Strong Fourier Sampling: Quantum Algorithms For Affine Groups And Hidden Shifts, Cristopher Moore, Daniel Rockmore, Alexander Russell, Leonard J. Schulman

Dartmouth Scholarship

Many quantum algorithms, including Shor’s celebrated factoring and discrete log algorithms, proceed by reduction to a hidden subgroup problem, in which an unknown subgroupH of a group G must be determined from a quantum state ψ over G that is uniformly supported on a left coset of H. These hidden subgroup problems are typically solved by Fourier sampling: the quantum Fourier transform of ψ is computed and measured. When the underlying group is nonabelian, two important variants of the Fourier sampling paradigm have been identified: the weak standard method, where only representation names are measured, and the strong standard method, …

Using Fuzzy-Word Correlation Factors To Compute Document Similarity Based On Phrase Matching, Jun Won Lee, Yiu-Kai D. Ng

Faculty Publications

One of the Web information Retrieval (IR) problems these days is to identify redundant information that exist in (replicated) Web documents. These documents can easily be found in several forms, such as documents in different versions, small documents combined with others to form a larger document, etc. As the Web is becoming more and more popular, the number of documents on the Web is increasing on a daily basis, and filtering redundant ones among this huge number of documents becomes a more difficult and an urgent task. As one of the solutions to this problem, we present a new method …

Estimating Business And Residential Water Supply Interruption Losses From Catastrophic Events, Nicholas Brozovic, David L. Sunding, David Zilberman

Daugherty Water for Food Global Institute: Faculty Publications

Following man-made or natural catastrophes, widespread and long-lasting disruption of lifelines can lead to economic impacts for both business and residential lifeline users. As a result, the total economic losses caused by infrastructure damage may be much higher than the value of damage to infrastructure itself. In this paper, we consider the estimation of economic impacts on businesses and residential consumers resulting from water supply disruption. The methodology we present for estimating business interruption losses assumes that marginal losses are increasing in the severity of disruption and that there may be a critical water availability cutoff below which business activity …

Fast-Converging Tatonnement Algorithms For The Market Problem, R Cole, L Fleischer

Computer Science Technical Reports

Why might markets tend toward and remain near equilibrium prices? In an effort to shed light on this question from an algorithmic perspective, this paper defines and analyzes two simple tatonnement algorithms that differ from previous algorithms that have been subject to asymptotic analysis in three significant respects: the price update for a good depends only on the price, demand, and supply for that good, and on no other information; the price update for each good occurs distributively and asynchronously; the algorithms work (and the analyses hold) from an arbitrary starting point. Our algorithm introduces a new and natural update …

An Overview Of Snow Photochemistry: Evidence, Mechanisms And Impacts, A M. Grannas, A E. Jones, Jack E. Dibb, M Ammann, Cort Anastasio, H J. Beine, M Bergin, J Bottenheim, C S. Boxe, G Carver, G Chen, J H. Crawford, Florent Domine, M M. Frey, M I. Guzman, D E. Heard, D Helmig, M R. Hoffmann, R E. Honrath, L Gregory Huey, Manuel Hutterli, H W. Jacobi, P Klan, Barry Lefer, J Mcconnell, J Plane, R Sander, J Savarino, P B. Shepson, W R. Simpson, J R. Sodeau, R Von Glasow, R Weller, E W. Wolff, T Zhu

Earth Sciences

It has been shown that sunlit snow and ice plays an important role in processing atmospheric species. Photochemical production of a variety of chemicals has recently been reported to occur in snow/ice and the release of these photochemically generated species may significantly impact the chemistry of the overlying atmosphere. Nitrogen oxide and oxidant precursor fluxes have been measured in a number of snow covered environments, where in some cases the emissions significantly impact the overlying boundary layer. For example, photochemical ozone production (such as that occurring in polluted mid-latitudes) of 3-4 ppbv/day has been observed at South Pole, due to …