Digital Commons Network^™

Aesthetic Journeys, Johanna Brewer, Scott Mainwaring, Paul Dourish

Computer Science: Faculty Publications

Researchers and designers are increasingly creating technologies intended to support urban mobility. However, the question of what mobility is remains largely under-examined. In this paper we will use the notion of aesthetic journeys to reconsider the relationship between urban spaces, people and technologies. Fieldwork on the Orange County bus system and in the London Underground leads to a discussion of how we might begin to design for multiple mobilities.

Balancing The Conservation Of Wildlife Habitat With Road Access For Subsistence Hunting In Yakutat, Alaska, Colin S. Shanley

Biological Sciences

"This thesis was an interdisciplinary investigation with the goal of balancing the conservation of wildlife habitat with road access for subsistence hunting in Yakutat, Alaska. The problem posed by land managers and subsistence moose hunters revolved around the use of off-highway vehicles (OHVs; e.g. 'four-wheelers') for subsistence moose hunting and the potential disturbance OHVs have on moose. This complex social-ecological problem is becoming an increasingly common management dilemma faced by rural mixed cash-subsistence communities across the Circumpolar North. I addressed this problem in two chapters with a combination of methods from wildlife ecology, landscape modeling, subsistence land-use, and scenario planning. …

King Eider Migration And Seasonal Interactions At The Individual Level, Steffen Oppel

Biological Sciences

Seasonal interactions describe how events during one season of the annual cycle of a migratory bird affect its fitness in subsequent seasons. Understanding the strength and mechanism of seasonal interactions is important to predict how migratory birds will respond to future challenges caused by habitat loss and climate change. This dissertation explores seasonal interactions between different stages of the annual cycle in an arctic-breeding sea duck, the King Eider (Somateria spectabilis). Concerns over recent population declines and potential effects of climate change on marine habitats used by the species highlight the need for a better understanding of its life history. …

Ontology Generation, Information Harvesting And Semantic Annotation For Machine-Generated Web Pages, Cui Tao

Theses and Dissertations

The current World Wide Web is a web of pages. Users have to guess possible keywords that might lead through search engines to the pages that contain information of interest and browse hundreds or even thousands of the returned pages in order to obtain what they want. This frustrating problem motivates an approach to turn the web of pages into a web of knowledge, so that web users can query the information of interest directly. This dissertation provides a step in this direction and a way to partially overcome the challenges. Specifically, this dissertation shows how to turn machine-generated web …

Quantifying The Effects Of Land Use Change On Stream Ecosystems For Use In Ecological Risk Assessment, Katherine Sciera

All Dissertations

Land disturbance often results in a cascade of physical and chemical stressors to aquatic ecosystems which can impact their biotic integrity. This study examined three developing watersheds near Greenville, SC to evaluate the quantitative relationships between the physical stressors associated with land use alterations and biotic integrity. More specifically, the objectives of this study were to 1) quantify the mechanisms of aquatic ecosystem degradation in streams impacted by watershed urbanization, 2) demonstrate the use of quantitative relationships among the physical, chemical, and biological stressors associated with land use change in an established ecological risk assessment framework, and 3) identify the …

Synthesis, Structure And Magnetic Properties Of Oxy-Anion Based Magnetic Solids Containing Transition Metal Oxide Nanostructures, Kulugammana Gedera Ranmohotti

All Dissertations

Inline with the focus of our research, my goal for this dissertation study is to further explore new classes of magnetic insulators exhibiting novel properties. The scope of this work is twofold: 1) the exploratory synthesis of polyanion-based mixed-framework compounds containing transition metal oxide magnetic nanostructures, and 2) the investigation of the structure/property correlation with respect to the spin couplings in confined lattices. These studies are of fundamental and technological importance regarding the long-term development of low-dimensional magnetic solids for device applications in especially information storage and quantum computing. Several interesting and significant transition metal based silicate, phosphate arsenate and …

Surface Energy Balance And Melt Thresholds Over 11 Years At Taylor Glacier, Antarctica, Matthew James Hoffman, Andrew G. Fountain, Glen E. Liston

Geography Faculty Publications and Presentations

In the McMurdo Dry Valleys, Victoria Land, Antarctica, melting of glacial ice is the primary source of water to streams, lakes, and associated ecosystems. To understand geochemical fluxes and ecological responses to past and future climates requires a physically based energy balance model. We applied a one-dimensional model to one site on Taylor Glacier using 11 years of daily meteorological data and seasonal ablation measurements. Inclusion of transmission of solar radiation into the ice was necessary to accurately model summer ablation and ice temperatures. Results showed good correspondence between calculated and measured ablation and ice temperatures over the 11 years. …

Analysis And Interpretation Of Volcano Deformation In Alaska: Studies From Okmok And Mt. Veniaminof Volcanoes, Thomas J. Fournier

Geosciences

Four studies focus on the deformation at Okmok Volcano, the Alaska Peninsula and Mt. Veniaminof. The main focus of the thesis is the volcano deformation at Okmok Volcano and Mt. Veniaminof, but also includes an investigation of the tectonic related compression of the Alaska Peninsula. The complete data set of GPS observations at Okmok Volcano are investigated with the Unscented Kalman Filter time series analysis method. The technique is shown to be useful for inverting geodetic data for time dependent non-linear model parameters. The GPS record at Okmok from 2000 to mid 2007 shows distinct inflation pulses which have several …

Oblique Impact Cratering: A Comparison Of Low-Velocity Experiments To High-Velocity Experiments, Katie K. Hessen

Geosciences

Previous impact cratering experiments performed by Gault and Wedekind (1978), used high-velocity impactors (~1 km/s to 7 km/s) to quantify how impact angle affects crater morphology and ejecta pattern. Low velocity (144 m/s to 260 m/s) impact experiments were conducted in a vacuum chamber with a basaltic sand target material and impact angles ranging from 0.5° to 90° (vertical) at the Impact Cratering Laboratory at the University of Tokyo Kashiwa. The crater morphology and ejecta distribution from low velocity impacts are then compared to results from the higher velocity projectiles. When adjustments are made to the low-velocity measurements to account …

Agenda: Managing Oil And Gas Development In Colorado: The New Cogcc Rules, University Of Colorado Boulder. Natural Resources Law Center

Managing Oil and Gas Development in Colorado: The New COGCC Rules (December 16)

NRLC Hot Topic held on December 16, 2008 from 12:00 noon to 1:30 p.m. at the offices of Hogan and Hartson, Denver, Colorado.

Panelists from COGCC, the oil & gas industry, and environmental community, will present their perspectives on the soon-to-be-issued rules on oil and development in Colorado. Discussion and questions from attendees will follow.

New Area Legislators – Introduction To Wmu, John M. Dunn

WMU President John Dunn

No abstract provided.

Promoting Supportive Relationships In Youth Programs: A Self-Determination Theory Perspective, Mat Duerden, Ann Gillard

Journal of Youth Development

Although research suggests that positive contact with non- parental adults is developmentally beneficial for youth; many adolescents do not have access to such relationships. It is important that adults structure existing relationships to optimize positive youth development. Relationships with adults, who support youth’s needs for autonomy, relatedness, and competence, provide youth with scaffolding as they navigate their way through adolescence. Self-Determination Theory offers a straight-forward approach to understanding the elements of contexts that best promote the development of supportive relationships. The purpose of this paper is to review the literature concerning youth-adult relationships, including their associated prevalence and developmental benefits …

Delay-Induced Destabilization Of Entrainment Of Nerve Impulses On Ephaptically Coupled Nerve Fibers, Evangelos A. Coutsias, Mohit H. Adhikari, John K. Mciver

Branch Mathematics and Statistics Faculty and Staff Publications

We study the effect of delay on the synchronization of two nerve impulses traveling along two ephaptically coupled, unmyelinated nerve fibers. The system is modeled as a pair of delay-coupled Fitzhugh-Nagumo equations. A multiple-scale perturbation approach is used for the analysis of these equations in the limit of weak coupling. In the absence of delay, two pulses with identical speeds are shown to be entrained precisely. However, as the delay is increased beyond a critical value, we show that this precise entrainment becomes unstable. We make quantitative estimates for the actual values of delay at which this can occur in …

Lagrangian Analysis Of Low Altitude Anthropogenic Plume Processing Across The North Atlantic, E. Real, K. S. Law, H. Schlager, A. Roiger, H. Huntrieser, J. Methven, M. Cain, J. Holloway, J. A. Neuman, T. Ryerson, F. Flocke, J. De Gouw, E. Atlas, S. Donnelly, D. Parrish

Chemistry Faculty Publications

The photochemical evolution of an anthropogenic plume from the New-York/Boston region during its transport at low altitudes over the North Atlantic to the European west coast has been studied using a Lagrangian framework. This plume, originally strongly polluted, was sampled by research aircraft just off the North American east coast on 3 successive days, and then 3 days downwind off the west coast of Ireland where another aircraft re-sampled a weakly polluted plume. Changes in trace gas concentrations during transport are reproduced using a photochemical trajectory model including deposition and mixing effects. Chemical and wet deposition processing dominated the evolution …

Integrated Approach To Airborne Laser Communication, James A. Louthain

Theses and Dissertations

Lasers offer tremendous advantages over RF communication systems in bandwidth and security, due to their ultra-high frequency and narrow spatial beamwidth. Atmospheric turbulence causes severe received power variations and high bit error rates (BERs) in airborne laser communication. Airborne optical communication systems require special considerations in size, complexity, power, and weight. Conventional adaptive optics systems correct for the phase only and cannot correct for strong scintillation, but here the two transmission paths are separated sufficiently so that the strong scintillation is \averaged out" by incoherently summing up the two beams in the receiver. This requisite separation distance is derived for …

A Modeling And Spatio-Temporal Analysis Framework For Monitoring Environmental Change Using Npp As An Ecosystem Indicator, Robert Crabtree, Christopher Potter, Randall Mullen, Jennifer Sheldon, Shengli Huang, Joshua Harmsen, Ann Rodman, Cathie Jean

United States National Aeronautics and Space Administration: Publications

We present and describe a modeling and analysis framework for monitoring protected area (PA) ecosystems with net primary productivity (NPP) as an indicator of health. It brings together satellite data, an ecosystem simulation model (NASA–CASA), spatial linear models with autoregression, and a GIS to provide practitioners a low-cost, accessible ecosystem monitoring and analysis system (EMAS) at landscape resolutions. The EMAS is evaluated and assessed with an application example in Yellowstone National Park aimed at identifying the causes and consequences of drought. Utilizing five predictor covariates (solar radiation, burn severity, soil productivity, temperature, and precipitation), spatio-temporal analysis revealed how landscape controls …

Regular Second Order Perturbations Of Binary Black Holes: The Extreme Mass Ratio Regime, Carlos O. Lousto, Hiroyuki Nakano

Articles

In order to derive the precise gravitational waveforms for extreme mass ratio inspirals (EMRI), we develop a formulation for the second order metric perturbations produced by a point particle moving in the Schwarzschild spacetime. The second order waveforms satisfy a wave equation with an effective source build up from products of the first order perturbations and its derivatives. We have explicitly regularized this source at the horizon and at spatial infinity. We show that the effective source does not contain squares of the Dirac’s delta and that perturbations are regular at the particle location. We introduce an asymptotically flat gauge …

Sub-Circuit Selection And Replacement Algorithms Modeled As Term Rewriting Systems, Eric D. Simonaire

Theses and Dissertations

Intent protection is a model of software obfuscation which, among other criteria, prevents an adversary from understanding the program’s function for use with contextual information. Relating this framework for obfuscation to malware detection, if a malware detector can perfectly normalize a program P and any obfuscation (variant) of the program O(P), the program is not intent protected. The problem of intent protection on programs can also be modeled as intent protection on combinational logic circuits. If a malware detector can perfectly normalize a circuit C and any obfuscation (variant) O(C) of the circuit, the circuit is not intent protected. In …

A Small Sample Correction For Estimating Attributable Risk In Case-Control Studies, Daniel B. Rubin

U.C. Berkeley Division of Biostatistics Working Paper Series

The attributable risk, often called the population attributable risk, is in many epidemiological contexts a more relevant measure of exposure-disease association than the excess risk, relative risk, or odds ratio. When estimating attributable risk with case-control data and a rare disease, we present a simple correction to the standard approach making it essentially unbiased, and also less noisy. As with analogous corrections given in Jewell (1986) for other measures of association, the adjustment often won't make a substantial difference unless the sample size is very small or point estimates are desired within fine strata, but we discuss the possible utility …

Bayesian Model Averaging For Clustered Data: Imputing Missing Daily Air Pollution Concentration, Howard H. Chang, Francesca Dominici, Roger D. Peng

Johns Hopkins University, Dept. of Biostatistics Working Papers

The presence of missing observations is a challenge in statistical analysis especially when data are clustered. In this paper, we develop a Bayesian model averaging (BMA) approach for imputing missing observations in clustered data. Our approach extends BMA by allowing the weights of competing regression models for missing data imputation to vary between clusters while borrowing information across clusters in estimating model parameters. Through simulation and cross-validation studies, we demonstrate that our approach outperforms the standard BMA imputation approach where model weights are assumed to be the same for all clusters. We then apply our proposed method to a national …

Organic Chemostratigraphic Markers Characteristic Of The (Informally Designated) Anthropocene Epoch, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Recognizing the tremendous collective impact of humans on the environment in the industrial age, the proposed designation of the current time period as the Anthropocene Epoch has considerable merit. One of the signature activities during this time continues to be the intensive extraction, processing, and combustion of fossil fuels. While fossil fuels themselves are naturally-occurring, they are most often millions of years old and associated with deeply buried strata. They may be found at the surface, for example, as natural oil seeps or coal seam outcrops, but these are relatively rare occurrences. Fossil fuels and their myriad by-products become the …

Confidence Intervals For A Common Mean With Missing Data With Applications In An Aids Study, Hua Liang, Haiyan Su, Guohua Zou

Department of Applied Mathematics and Statistics Faculty Scholarship and Creative Works

In practical data analysis, nonresponse phenomenon frequently occurs. In this paper, we propose an empirical likelihood based confidence interval for a common mean by combining the imputed data, assuming that data are missing completely at random. Simulation studies show that such confidence intervals perform well, even when the missing proportion is high. Our method is applied to an analysis of a real data set from an AIDS clinic trial study.

An Online Learning Approach To Community Building Among Asian Journalists, Ma. Mercedes T. Rodrigo, Violet B. Valdez

Department of Information Systems & Computer Science Faculty Publications

This chapter describes a master's program in journalism designed for professional Asian journalists which has drawn students from 13 Asian countries and is run by faculty members from five countries. The program uses blended learning methods combining synchronous, asynchronous, and classroom-based approaches. An exploratory study was conducted to describe the strategies used by the students and teachers to build a community of learners (Garrison, Anderson, & Archer, 2000) and hence achieve the program's learning goals. The study took into consideration cultural differences, in particular, those referring to educational experiences. Results show that the respondents tended to use the strategies of …

Ac System Equipment Specification, Installation And Operational Options For Improved Indoor Humidity Control, Florida Solar Energy Center, Don B. Shirey Iii

FSEC Energy Research Center®

High-efficiency home designs have significantly reduced sensible cooling loads, and some building codes and IAQ standards have begun requiring continuous outdoor ventilation air. These trends have led to an increased prevalence of high indoor humidity conditions (Rudd and Henderson 2007). This paper presents a summary of low-cost or no-cost equipment selection and operation options for conventional residential air-conditioning equipment than can result in lower indoor humidity levels. These options should be evaluated and employed to the extent possible prior to considering the added first cost and operating costs of separate dehumidification equipment.

Sediment Transport Rate-Based Model For Rainfall-Induced Soil Erosion, Zhi Qiang Deng, João L.M.P. De Lima, Hoon Shin Jung

Faculty Publications

A one-dimensional mathematical model, termed sediment transport rate-based model, is developed for determining rainfall-induced soil erosion and sediment transport. The model is comprised of (1) the kinematic-wave equation for overland flow, (2) a transport rate-based advection equation for rainfall-induced soil erosion and sediment transport, and (3) a semi-Lagrangian algorithm for numerical solution of the soil erosion and sediment transport equation. A series of soil flume experiments under simulated rainfalls were conducted to simulate the overland flow and sediment transport and to test the sediment transport rate-based model. Numerical results of sediment transport rate-based model indicate that (i) hydrographs display an …

The Tiffanian Land-Mammal Age (Middle And Late Paleocene) In The Northern Bighorn Basin, Wyoming, Ross Secord

Department of Earth and Atmospheric Sciences: Faculty Publications

The Tiffanian North American land-mammal age is an informal biochronologic unit that spans 4.5 myr of the middle and late Paleocene. It is preceded and succeeded by the Torrejonian and Clarkforkian land-mammal ages, respectively. The Tiffanian was initially based on a small collection of mammals from southern Colorado, but faunas of Tiffanian age are now known throughout the Rocky Mountain region. The richest and most complete sequence of middle and late Tiffanian faunas known occurs in the northern Bighorn Basin. These faunas are the primary basis for regional Tiffanian biochronology. The Bighorn Basin sequence is also important because it preserves …

The Acs Survey Of Galactic Globular Clusters. Vi. Ngc 6366: A Heavily Stripped Galactic Globular Cluster, Nathaniel E. Q. Paust, Antonio Aparicio, Giampaolo Piotto, I. Neill Reid, Jay Anderson, Ata Sarajedini, Luigi R. Bedin, Brian Chaboyer

Dartmouth Scholarship

We have used observations obtained as part of the Hubble Space Telescope/ACS Survey of Galactic globular clusters (GCs) to construct a color-magnitude diagram for the bulge cluster, NGC 6366. The luminosity function derived from those data extends to M _F606W ~ 9, or masses of ~0.3 M _☉. Unlike most GCs, the mass function peaks near the main-sequence turnoff with significantly fewer low-mass stars even after correction for completeness and mass segregation. Using a multimass King model, we extrapolate the global cluster behavior and find the global mass function to be poorly matched by a power law, with …

The Study Of Price Accept Threshold For The ??Lue Highway??Tour Of The North-East Region In Taiwan, Hung-Yen Chou, Jin-Long Lu, Chiang Fu

Journal of Marine Science and Technology–Taiwan

The “Blue Highway” in the NE region of Taiwan includes the tour itineraries of Keelung-Suao, Suao-Hualien and Keelung-Hualien, each with its individual oceanic scenic features and its potential corresponding onshore scenic spots. This study explores the relationship between the “Blue Highway” tour portfolios and price attributes to collect the preference recognition of the public concerning the NE region “Blue Highway” tour itineraries and prices with the stated preference method. The utility function of the discrete choice model assumes the impact effect among attributes to be in a linear relationship plus percentages. The price threshold model improves the assumption of this …

Theoretical Elucidation On The Corrosion Tube Growth Mechanism Of Mild Steel In The Effect Of Ph On Oxygen Corrosion At Elevated Pressures, Ming-Te Liang

Journal of Marine Science and Technology–Taiwan

The major purpose of this paper is the theoretical elucidation of the corrosion tube growth mechanism of mild steel occurred from the effect of pH value and oxygen corrosion at elevated pressure provided by Riggs et al. [6]. Based on the Nernst-Planck equation, continuity principle, Green's theorem, Stokes's theorem and the equation of Newton's second law of motion, the mechanism of corrosion tube development can be explained theoretically. The Bernoulli sum is contant at any cross-section of tubular corrosion product. The implication of the present results are theoretically enhanced the formation of corrosion tube mechanism.

The Manpower Supply Planning And Shift Setting For Mass Rapid Transit Carriage Maintenance In Short-Term Operations, Shangyao Yan, Chia-Hung Chen, Miawjane Chen

Journal of Marine Science and Technology–Taiwan

An effective carriage maintenance plan cannot only reduce the mass rapid transit system operating costs, but is also directly related to its safety and schedule punctuality. Traditionally, the arrangement of the carriage maintenance manpower supply has been based on staff experience, and has been performed manually following simple rules. This is not only time-consuming but often ineffective. Therefore, in this research, we incorporate flexible management strategies, different combinations of principles, and the related operating constraints, to develop a basic carriage maintenance manpower supply plan model. Furthermore, we construct an integrated model by modifying the basic model, which can help an …