Physical Sciences and Mathematics Commons^™

Constrained Feature Selection For Localizing Faults, Tien-Duy B. Le, David Lo, Ming Li

Research Collection School Of Computing and Information Systems

Developers often take much time and effort to find buggy program elements. To help developers debug, many past studies have proposed spectrum-based fault localization techniques. These techniques compare and contrast correct and faulty execution traces and highlight suspicious program elements. In this work, we propose constrained feature selection algorithms that we use to localize faults. Feature selection algorithms are commonly used to identify important features that are helpful for a classification task. By mapping an execution trace to a classification instance and a program element to a feature, we can transform fault localization to the feature selection problem. Unfortunately, existing …

On Robust Image Spam Filtering Via Comprehensive Visual Modeling, Jialie Shen, Deng, Robert H., Zhiyong Cheng, Liqiang Nie, Shuicheng Yan

Research Collection School Of Computing and Information Systems

The Internet has brought about fundamental changes in the way peoples generate and exchange media information. Over the last decade, unsolicited message images (image spams) have become one of the most serious problems for Internet service providers (ISPs), business firms and general end users. In this paper, we report a novel system called RoBoTs (Robust BoosTrap based spam detector) to support accurate and robust image spam filtering. The system is developed based on multiple visual properties extracted from different levels of granularity, aiming to capture more discriminative contents for effective spam image identification. In addition, a resampling based learning framework …

Two Formulas For Success In Social Media: Learning And Network Effects, Liangfei Qiu, Qian Tang, Andrew B. Whinston

Research Collection School Of Computing and Information Systems

Recent years have witnessed an unprecedented explosion in information technology that enables dynamic diffusion of user-generated content in social networks. Online videos, in particular, have changed the landscape of marketing and entertainment, competing with premium content and spurring business innovations. In the present study, we examine how learning and network effects drive the diffusion of online videos. While learning happens through informational externalities, network effects are direct payoff externalities. Using a unique data set from YouTube, we empirically identify learning and network effects separately, and find that both mechanisms have statistically and economically significant effects on video views; furthermore, the …

Evolution Of Mobile Promoters In Prokaryotic Genomes., Mahnaz Rabbani

Electronic Thesis and Dissertation Repository

Mobile genetic elements are important factors in evolution, and greatly influence the structure of genomes, facilitating the development of new adaptive characteristics. The dynamics of these mobile elements can be described using various mathematical and statistical models. In this thesis, we focus on a specific category of mobile genetic elements, i.e. mobile promoters, which are mobile regions of DNA that initiate the transcription of genes. We present a class of mathematical models for the evolution of mobile promoters in prokaryotic genomes, based on data obtained from available sequenced genomes. Our novel location-based model incorporates two biologically meaningful regions of the …

Effectiveness Of A Spontaneous Carvacrol Nanoemulsion Against Salmonella Enterica Enteritidis And Escherichia Coli O157:H7 On Contaminated Broccoli And Radish Seeds, Kyle Landry, Sean Micheli, David Julian Mcclements, Lynne Mclandsborough

Kyle S Landry

A Multilayer Surface Detector For Ultracold Neutrons

Robert W. Pattie Jr.

Geology Of The Steens Area, Jane Claire Dirks-Edmunds

Jane Claire Dirks-Edmunds Documents

This document is part of a larger discussion in the Dr. Jane Claire Dirks-Edmunds Papers on the geology of Steens Mountain, a large fault-block mountain in Harney County, Oregon. Often confused for a mountain range because of its size and scope, Steens Mountain lies near the Oregon-Nevada border.

For a full-text searchable version of this document, refer to the Additional Files below.

Secular Variations Of Atomic Oxygen In The Mesopause Region Induced By Transient Gravity Wave Packets, Michael P. Hickey Ph.D., R. L. Walterscheid, Philip G. Richards

Michael P. Hickey

We employ a 2-dimensional, time-dependent, fully nonlinear model of minor species in the mesopause region and our Spectral Full-Wave Model to simulate the response of atomic oxygen (O) to a gravity wave packet in the mesopause region. We demonstrate that gravity waves affect the time-averaged distribution of O in the mesosphere and lower thermosphere (MLT) region through the constituent fluxes the waves induce. Our conclusions are based on simulations of two wave packets that violate the non-acceleration conditions through transience and dissipation. The net cycle-averaged effect of the waves is to significantly increase (by as much as 50%) the O …

New Sources For The Hot Oxygen Geocorona, P. G. Richards, Michael P. Hickey Ph.D., D. G. Torr

Michael P. Hickey

This paper investigates new sources of thermospheric non thermal (hot) oxygen due to exothermic reactions involving numerous minor (ion and neutral) and metastable species. Numerical calculations are performed for low latitude, daytime, winter conditions, with moderately high solar activity and low magnetic activity. Under these conditions we find that the quenching of metastable species are a significant source of hot oxygen, with kinetic energy production rates a factor of ten higher than those due to previously considered O2+ and NO+ dissociative recombination reactions. Some of the most significant new sources of hot oxygen are reactions involving quenching of O+(²D), O(¹D), …

Gravity Wave-Driven Fluctuations In The O2 Atmospheric (0-1) Nightglow From An Extended, Dissipative Emission Region, Michael P. Hickey Ph.D., G. Schubert, R. L. Walterscheid

Michael P. Hickey

The wave-driven fluctuations in the O2(0-1) atmospheric nightglow is modeled and the parameter (eta) is calculated using a model that accounts for either three-body recombination of atomic oxygen atoms alone to form the O2(b exp 1 Sigma(g)(+)) state directly, or by the further inclusion of the process that allows the formation of the O2(c exp 1 Sigma(u)(-)) intermediate state. The calculations are performed for a latitude of 18 deg N and for the months of March and June. The general results, which display how (eta) varies with wave period, horizontal wavelength, season, and chemical scheme, show that for given values …

Comparison Of Theories For Gravity Wave Induced Fluctuations In Airglow Emissions, R. L. Walterscheid, G. Schubert, Michael P. Hickey Ph.D.

Michael P. Hickey

A comparison is undertaken of theories for the gravity wave induced fluctuations in the intensity of airglow emissions and the associated temperature of the source region. The comparison is made in terms of Krassovsky's ratio ηE for a vertically extended emission region (ηE is the ratio of the vertically integrated normalized intensity perturbation to the vertically integrated normalized intensity-weighted temperature perturbation). It is shown that the formulas for ηE in the works by Tarasick and Hines (1990) and Schubert et al. (1991) are in agreement for the case of an inviscid atmosphere. The calculation of ηE using the theory of …

Effects Of Eddy Viscosity And Thermal Conduction And Coriolis Force In The Dynamics Of Gravity Wave Driven Fluctuations In The Oh Nightglow, Michael P. Hickey Ph.D.

Michael P. Hickey

Recently, Walterscheid et al. (1987) have described a dynamical-chemical model of wave-driven fluctuations in the OH nightglow which incorporated a five-reaction photochemical scheme and the dynamics of linearized acoustic-gravity waves in an isothermal, motionless atmosphere. The intensity oscillation (δI) about the time-averaged intensity (I0) and the temperature oscillation (δT) about the time-averaged temperature (T0) were related by means of the complex ratio η ≡ (δI/I0)/(δT/T0). One of the main conclusions of their work was that the inclusion of dynamical effects is absolutely essential for …

Wavelength Dependence Of Eddy Dissipation And Coriolis Force In The Dynamics Of Gravity Wave Driven Fluctuations In The Oh Nightglow, Michael P. Hickey Ph.D.

Michael P. Hickey

The theory of Walterscheid et al. (1987) to explain internal gravity wave induced oscillations in the emission intensity I and rotational temperature T of the OH nightglow was modified by Hickey (1988) to include the effects of eddy dissipation and Coriolis force. In the theory of Walterscheid et al. (1987) the ratio η = (δI/I0)/(δT/T0) (δ refers to a perturbation quantity, and a zero subscript refers to an average) was found to be independent of horizontal wavelength at long periods, while in the extended theory of Hickey (1988) some such dependence was …

Seasonal And Latitudinal Variations Of Gravity Wave-Driven Fluctuations In Oh Nightglow, Michael P. Hickey Ph.D., R. L. Walterscheid, G. Schubert

Michael P. Hickey

The seasonal and latitudinal variations of the gravity wave-driven fluctuations in the OH nightglow are investigated theoretically using a model that accounts for emission from an extended OH layer and includes the effects of eddy diffusivities in the gravity wave dynamics. The mean (unperturbed) state is obtained from a two-dimensional, nighttime model so that mean-state number densities, temperatures and eddy diffusivities are all self-consistent. Seasonal and latitudinal variations in the background OH nightglow emission and in the propagation and dissipation characteristics of the gravity waves influence how the OH nightglow modulations due to gravity waves depend on season and latitude. …

A Chemical-Dynamical Model Of Wave-Driven Sodium Fluctuations, Michael P. Hickey Ph.D., John M.C. Plane

Michael P. Hickey

A comprehensive chemical-dynamical model is used to investigate the interaction of gravity waves with twenty minor species involved in the atomic sodium chemistry in the mesopause region. We find that chemistry becomes important on the underside of the sodium layer, primarily below 85 km altitude, where the relative importance of chemistry in wave-driven sodium fluctuations increases with increasing wave period and increasing horizontal wavelength. We also find that for altitudes below 80 km an adequate determination of the effects of chemistry in these fluctuations requires the inclusion of several reactions related to ozone chemistry. However, the atomic Na density is …

New Sources For The Hot Oxygen Geocorona: Solar Cycle, Seasonal, Latitudinal, And Diurnal Variations, Michael P. Hickey Ph.D., P. G. Richards, D. G. Torr

Michael P. Hickey

This paper demonstrates the variability of thermospheric sources of hot oxygen atoms. Numerical calculations were performed for day and night, high and low solar activity, summer and winter, and low- and middle-latitude conditions. Under most conditions, reactions involving metastable species are more important hot O sources than previously considered dissociative recombination of O2+ and NO+. All the hot O sources are an order of magnitude lower at midnight than at noon. At night, dissociative recombination of O2+and NO+ are the most important sources. Quenching of vibrationally excited N2 (N2*) by O is the most important metastable source at night. Above …

Wave-Modified Mean Exothermic Heating In The Mesopause Region, Michael P. Hickey Ph.D., R. L. Walterscheid

Michael P. Hickey

We employ a model of wave-driven OH nightglow fluctuations to calculate the effects of gravity waves on the chemical exothermic heating due to reactions involving odd hydrogen and odd oxygen species in the mesopause region. Using a model based on time means and deviations from those means, it is demonstrated that gravity waves contribute to the time-average exothermic heating. The effect can be significant because the fractional fluctuations in minor species density can be substantially greater than the fractional fluctuation of the major gas density. Our calculations reveal that the waves mitigate the exothermic heating, demonstrating their potential importance in …

Front Matter

Journal of Digital Forensics, Security and Law

No abstract provided.

Masthead

Journal of Digital Forensics, Security and Law

No abstract provided.

Back Matter

Journal of Digital Forensics, Security and Law

No abstract provided.

Effects Of Aerial Exposure On Preservation Of Low-Temperature Calothrix Biosignatures In Silica Sinter From Queen's Laundry, Yellowstone National Park, Usa, Shana Kendall

Dissertations and Theses

Mineral-depositing hydrothermal ecosystems, such as the hot springs in Yellowstone National Park, provide an unparalleled opportunity to document how microbial biosignatures form and contribute to the body of evidence indicative of the microbial inhabitants of active hot springs. Mineralization of microbial communities in silica-depositing hot springs can result in the preservation of microbial biofacies in the geologic record. To determine the effects of prolonged aerial exposure on the preservation potential of mid-to-low temperature cyanobacteria dominated microbial communities that are typically permineralized in the siliceous sinter, modern biofacies samples of such communities were collected from the active and inactive parts of …

An Analytical Method For Detecting Toxic Metal Cations Using Cyclotriveratrylene Derivative Capped Gold Nanoparticles, Zachary R. Osner, Richard C. Holz, Daniel P. Becker

Chemistry Faculty Research and Publications

Cyclotriveratrylene-oxime (CTV-oxime) derivatives that terminate with a dithiolate linker were synthesized enabling the supramolecular scaffold to adhere to gold nanoparticles (AuNPs) with the bowl-shaped cavity of the CTV scaffold exposed for utilization in host–guest chemistry. Exposure of these CTV functionalized AuNPs to varying concentrations of di- and trivalent metal cations resulted in the formation of large CTV-AuNP polymeric clusters and an accompanying a shift in the plasmon resonance. These interactions between the CTV-AuNPs and the metal cations in solution provides proof-of-concept that supramolecular functionalized AuNPs can be used as a simple and straightforward, on-site detection system for toxic metal cations …

Propagation Of Non-Stationary Noise In Waveguides, Jonathan Samuel Ben-Benjamin

Dissertations, Theses, and Capstone Projects

This thesis consists of research regarding pulse and noise propagation in dispersive media. The research consists of three parts. In Part I we develop an approach for the propagation of non-stationary noise in waveguides, and in particular, we focus on the two-plate waveguide, which is a standard model for the ocean. he fundamental aim is to obtain the propagation of the space-time autocorrelation function. In our formulation, the noise is described by a Wigner spectrum, from which the autocorrelation function can be obtained. We discuss how to obtain the Wigner spectrum of a noise field from the Wigner spectrum of …

Studies On Bell's Theorem, Veli Ugur Guney

Dissertations, Theses, and Capstone Projects

In this work we look for novel classes of Bell's inequalities and methods to produce them. We also find their quantum violations including, if possible, the maximum one.

The Jordan bases method that we explain in Chapter 2 is about using a pair of certain type of orthonormal bases whose spans are subspaces related to measurement outcomes of incompatible quantities on the same physical system. Jordan vectors are the briefest way of expressing the relative orientation of any two subspaces. This feature helps us to reduce the dimensionality of the parameter space on which we do searches for optimization. The …

Accessing Medicinally-Relevant Scaffolds Via Organocatalyzed Cascade Reactions, Joshua Hadley Jones

Dissertations, Theses, and Capstone Projects

The field of asymmetric catalysis embodies the efforts of chemists to mimic the stereoselectivity routinely achieved by biological systems. Asymmetric organocatalysis, a sub-field of asymmetric catalysis, is broadly based on the catalytic activity of non-transition metal, small molecules that transmit chirality to substrates. This dissertation describes experimental work towards the construction of versatile, medicinally-relevant molecular scaffolds using chiral, diarylprolinol silyl ether organocatalysts. Specifically, these catalysts were used in 1-pot, iminium-enamine catalyzed cascade reactions to functionalize α,β-unsaturated aldehydes. A comprehensive review of iminium and enamine organocatalysis is provided, including its development towards iminium-enamine cascade reactions. This review provides background for the …

Large-Pore Mesoporous Organosilicas And Related Polymer Nanocomposites, Amanpreet Singh Manchanda

Dissertations, Theses, and Capstone Projects

The research work in this dissertation covers the synthesis of mesoporous organosilicas and (organo)silica/polymer nanocomposites. The content can be divided into 4 parts (8 chapters).

The first part of the dissertation is the introduction, which covers the background and progress in the field of mesoporous silicas, periodic mesoporous organosilicas and related inorganic/polymer nanocomposites. The second part of the dissertation (Chapter 2-5) involves the synthesis of mesoporous organosilicas from different organosilane precursors at mild acid concentration (0.1 M HCl) and low temperature (0 or 7 ℃) using Pluronic F127 (EO₁₀₆PO₇₀EO₁₀₆) as a surfactant template. Chapter …

Polymer Pen Printing: A Tool For Studying 2d Enzymatic Lithography And Printing 3d Carbon Features, Zhantong Mao

Dissertations, Theses, and Capstone Projects

Polymer Pen Lithography (PPL) is a promising molecular printing approach which combines the advantages of both microcontact printing (low cost, high-throughput) and the dip pen lithography (DPN) (arbitrary writing, high-resolution) into one cohesive lithography method to create 2 dimensional (2-D) patterns with micro/nano-features on different substrates. The goal of this dissertation is to design and develop a new tool based upon PPL, which is not limited to forming 2D parallel patterns, but can also create 3D complex microstructures, finding applications in both biotechnology and Micro-Electro-Mechanical systems (MEMS) technology. This novel approach is named Polymer Pen Printing. Different from PPL using …

Hybridized Criticality And Elementary Excitations In Lihof4, Haifu Ma

Dissertations, Theses, and Capstone Projects

In this dissertation, I study the magnetic properties of LiHoF₄. Quantum criticality in rare earth ferromagnet LiHoF₄ is complicated by the presence of strong crystal field and hyperfine interactions resulting, e.g., in incomplete mode softening reported by Rønnow et al. We construct a systematic framework for treating elementary excitations in this material across the phase diagram. These excitations interpolate between purely electronic, nuclear and lattice modes and exhibit two-types of quantum critical softening, both complete (as anticipated by elementary treatments, see e.g. Sachdev) but also incomplete, in close correspondence with nuclear scattering results.

Ordering And Topological Defects In Solids With Quenched Randomness, Thomas Chapman Proctor

Dissertations, Theses, and Capstone Projects

We explore multiple different examples of quenched randomness in systems with a continuous order parameter. In all these systems, it is shown that understanding the effects of topology is critical to the understanding of the effects of quenched randomness.

We consider n-component fixed-length order parameter interacting with a weak random field in d = 1,2,3 dimensions. Relaxation from the initially ordered state and spin-spin correlation functions have been studied on lattices containing hundreds of millions sites. At n - 1 < d presence of topological structures leads to metastability, with the final state depending on the initial condition. At n …

Synthesis Panel Presentation & Discussion, Ernie Estevez, Susan Bell, Shawn M. Landry, Aaron Brown, Lindsay Cross, Holly Greening

School of Geosciences Faculty and Staff Publications

No abstract provided.