Digital Commons Network^™

Psr J1856+0245: Arecibo Discovery Of A Young Energetic Pulsar Coincident With The Tev G-Ray Source Hess J1857+026, J. W.T. Hessels, D. J. Nice, B. M. Gaensler, V. M. Kaspi, D. R. Lorimer, D. J. Champion, A. G. Lyne, M. Kramer, J. M. Cordes, P. C.C. Freire, Fredrick A. Jenet

Physics & Astronomy Faculty Publications

We present the discovery of the Vela-like radio pulsar J1856+0245 in the Arecibo PALFA survey. PSR J1856+0245 has a spin period of 81 ms, a characteristic age of 21 kyr, and a spin-down luminosity Ä– p 4.6 x 10 36 ergs s-1. It is positionally coincident with the TeV γ-ray source HESS J1857+026, which has no other known counterparts. Young, energetic pulsars create wind nebulae, and more than a dozen pulsar wind nebulae have been associated with very high energy (100 GeV-100 TeV) γ-ray sources discovered with the HESS telescope. The γ-ray emission seen from HESS J1857+026 is potentially produced …

Life Cycle Analysis For The Cultivation And Combustion Of Miscanthus For Biofuel Compared With Natural Gas, Amanda Ashworth, Charles West, Michael Popp, Mireille Montrejaud-Vignoles, Caroline Sablayrolles, Gabrielle Benoit

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

As negative environmental and economic impacts of fossil fuels have escalated, so has the importance of renewable bioenergy crops whose feedstocks are noncompetitive with food supplies. Compared with fossil fuels, use of lignocellulosic feedstocks offers potential for greenhouse gas reduction and highly positive net energy returns because of low input demand and high yields per unit of land area, thus making them advantageous for the emerging biofuel industry. The aim of this study was to simulate environmental impacts of producing a biofuel grass for combustion use based on the inventory of inputs and their effects on eutrophication of surface waters; …

Using Combined Prediction Models To Quantify And Visualize Stormwater Runoff In An Urban Watershed, Keshia Koehn, Cristina Scarlat, Kristofor Brye

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Stormwater runoff can transport nutrients, sediments, chemicals, and pathogens to surface waterbodies. Managing runoff is crucial to preserving water quality in rapidly developing urban watersheds like those in Northwest Arkansas. A watershed containing the majority of the University of Arkansas campus was designated as the study area because stormwater from it drains into the West Fork of the White River, designated as an impaired waterbody due to siltation. The project objective was to develop methodology to test existing stormwater drainage infrastructure, identify potential areas of improvement, and estimate potentially contaminated runoff by combining two widely used prediction models. The U.S. …

Using Biosolids To Enhance Phytoremediation Of Oil-Contaminated Soil, Heather N. Markway, Duane C. Wolf, Kaaron J. Davis, Edward E. Gbur

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

While the plant rhizosphere and associated microbial processes have been shown to amplify the degradation rate of chemical residues in soils, phytoremediation can be a slow process. The objective of this greenhouse study was to determine if the addition of biosolids as an organic soil amendment would enhance growth of plants in oil-contaminated soil and thus potentially increase effectiveness of phytoremediation. Pearl millet (Pennisetum glaucum (L.) R. Br.) or sudangrass (Sorghum sudanense (Piper) Stapf (Piper)) was grown in a Captina silt loam (finesilty, siliceous, mesic Typic Fragiudults) contaminated with 5% crude oil (v/w) and amended with 24 g biosolids/kg soil. …

How Are Preferences Revealed?, John Beshears, James J. Choi, David Laibson, Brigitte C. Madrian

Faculty Publications

Revealed preferences are tastes that rationalize an economic agent's observed actions. Normative preferences represent the agent's actual interests. It sometimes makes sense to assume that revealed preferences are identical to normative preferences. But there are many cases where this assumption is violated. We identify five factors that increase the likelihood of a disparity between revealed preferences and normative preferences: passive choice, complexity, limited personal experience, third-party marketing, and intertemporal choice. We then discuss six approaches that jointly contribute to the identification of normative preferences: structural estimation, active decisions, asymptotic choice, aggregated revealed preferences, reported preferences, and informed preferences. Each …

Yosemite National Park: The Continuous Evolution Of Human–Black Bear Conflict Management, Joseph S. Madison

Human–Wildlife Interactions

Human–bear conflicts are all too common throughout much of the United States (Ziegltrum 2008) and the world (Lemelin 2008, Worthy and Foggin 2008). Typically, they are a result of the availability of human food and garbage to bears (Beckmann and Lackey 2008, Thiemann et al. 2008). As people continue to build homes farther into the wildland–urban interface, the level of conflicts with bears can be expected only to increase (Conover 2008). Despite the widespread range of human–bear conflict, there is no place with quite the same problem as the Sierra Nevada mountain range of California, particularly in Yosemite National Park.

Modeling Wildlife Damage To Crops In Northern Indiana, Mónica I. Retamosa, Lee A. Humberg, James C. Beasley, Olin E. Rhodes Jr.

Human–Wildlife Interactions

Comprehensive information on crop damage by wildlife species is critical if effective strategies for controlling wildlife damage are to be formulated. Discriminating how landscape composition and configuration attributes influence crop damage is important for implementing landscape management techniques to resolve human–wildlife conflicts. We analyzed crop damage data from 100 corn fields and 60 soybean fields located in the Upper Wabash River Basin of northern Indiana during 2003 and 2004. We used negative binomial regression to model the rate of damage to corn and soybean crops in response to local and landscape variables. Rate of crop damage was best predicted by …

Trans Fatty Acids Provide Evidence Of Anthropogenic Feeding By Black Bears, Gregory W. Thiemann, Randal S. Stahl, Sharon Baruch-Mordo, Stewart W. Breck

Human–Wildlife Interactions

Bears (Ursus spp.) that become conditioned to anthropogenic food sources pose a risk to human safety and generally need to be relocated, rehabilitated, or destroyed. Identifying food-conditioned bears may be difficult if the animal is not captured or killed while immediately engaged in the nuisance behavior. Fatty acid signature analysis has been used to examine the dietary habits of bears and other carnivores and is based on the predictable incorporation of ingested fatty acids into the consumer’s fat stores. Unusual fatty acids that are available in only a few food types may be particularly useful dietary markers. In this …

In The News, Spring 2008, Joe N. Caudell, Rob Mcilvan

Human–Wildlife Interactions

The Daily Globe of Ironwood, Michigan, reported on a new Wisconsin regulation that went into effect on October 1, 2007. People who feed deer for non-hunting purposes are required to stop doing so for at least 30 days if bear or elk begin using the site. Deer-feeding currently is banned in 26 Wisconsin counties. The amount and location where bait or feed may be distributed is regulated in all of the other counties in the state. This new regulation is aimed at protecting homeowners, motorists, and the small but growing elk herd by reducing disease transmission, automobile collisions, and other …

Avoiding The Blame Game In Managing Problem Black Bears, Michael L. Wolfe

Human–Wildlife Interactions

In June 2007 a black bear (Ursus americanus) took an 11-year-old boy from the tent in which he was sleeping at a semi-wilderness campsite in the Uinta National Forest in Utah and killed him. The off ending bear, a 381-pound adult male, subsequently was destroyed by personnel of the Utah Division of Wildlife Resources and USDA/APHIS/Wildlife Services. The tragic incident, raises the number of recorded human fatalities caused by black bears during the period 1900–2007 to about 52. Although deaths caused by large carnivores are rare, the media attention associated with them focuses public concern for the responsibility …

Formalism: From Racial Integration To Same-Sex Marriage, Holning Lau

UC Law Journal

Parents Involved in Community Schools v. Seattle School District, No. i concerned racial integration in public schools; however, the case has a doctrinal impact that extends beyond the context of race, extending specifically to same-sex marriage. Ironically, the five Supreme Court Justices who formed a majority in the casefour of whom are commonly labeled social conservatives - bolstered the case for same-sex marriage. They did so by introducing a new exercise of formalism to equal protection analysis. Specifically, they created doctrine that supports the argument that same-sex marriage bans warrant heightened scrutiny because such bans discriminate on the basis of …

The Philosophy Of Forensic Scientific Identification, Allan Jamieson

UC Law Journal

This paper outlines a convenient categorization of the means by which evidence moves from crime scene to court; the forensic process. This process is proposed to include; Protection, Recording, Collection, Analysis, Interpretation, Evaluation, and Presentation.

A rational scientific approach to the process is discussed in terms of a cycle of observation, and hypothesis building and testing. The matching process, common to almost all forensic sciences, is assessed in the forensic and scientific contexts. Particular emphasis is recommended to differentiate between the processes of interpretation and evaluation. 'Interpretation' is proposed to be the results of the analytical process with no case-dependent …

Conceptual Hurdles To The Application Of Atkins V. Virgina, Lois A. Weithorn

UC Law Journal

In its 2002 decision in Atkins v. Virginia, the United States Supreme Court held that the Eighth Amendment's prohibition against cruel and unusual punishment precludes the execution of "mentally retarded offender[s]." Despite the apparent "brightline" clarity of an absolute ban on the execution of mentally retarded offenders, the determination of which offenders fall within the protected group is deceivingly complex. The meanings of the concepts of "mental retardation," "intelligence," and "adaptive behavior" are-like the standards of decency guiding the Court-continually evolving, and are subjects of ongoing reevaluation and debate. Given what is at stake in Atkins assessments, lawmakers, jurists, practitioners, …

Why Binomial Distributions Do Not Work As Proof Of Employment Discrimination, Ben Ikuta

UC Law Journal

Although it is possible for employer discrimination policies to be facially apparent in employment discrimination cases, usually employer policies are not overtly discriminatory. In those situations where it is not apparent, the only method of proving a prima facie case of discrimination in most systemic disparate treatment instances is to show a pattern of discrimination in the employer's hiring decisions. Since these patterns can usually "be identified and analyzed in quantitative form," cases rely primarily, and often exclusively, on statistics. If the plaintiff offers statistics that indicate a hiring practice that is unlikely absent discrimination, then the plaintiff is deemed …

The Myth Of "Lucky" Patent Verdicts: Improving The Quality Of Appellate Review By Incorporating Fuzzy Logic In Jury Verdicts, Michael T. Nguyen

UC Law Journal

Fuzzy logic, a relatively new mathematical concept, has emerged over the past few decades as an effective tool to model complexity and uncertainty. In a nutshell, fuzzy logic recognizes that truth is not always black or white, but rather, truth can be measured in shades of gray. Patents, because they rely on language to claim inventions, are fuzzy legal concepts. Fuzzy logic may help to simplify the jurors' comprehension of complex real-world problems in patent law.

In this Note, I propose a "fuzzy" special verdict form and procedure for "defuzzifying" the verdict that would allow the jury the freedom to …

Cognitive Bias And The Motherhood Penalty, Stephen Benard, In Paik, Shelley J. Correll

UC Law Journal

Women experience significant penalties in wages and other labor market outcomes when they have children. In this Article, we review and evaluate theory and research on cognitive bias and the motherhood penalty. Several theories predict that discrimination in the form of cognitive bias accounts for at least a part of the penalty that mothers experience. These theories include status characteristics theory, the stereotype content model, the shifting standards model, and the lack of fit model. Empirical evidence from controlled laboratory experiments and field studies strongly supports the general hypothesis that women experience labor market discrimination when they have children. There …

Measuring The Tax Subsidy In Private Equity And Hedge Fund Compensation, Thomas J. Brennan, Karl S. Okamoto

UC Law Journal

This Article offers a new analysis of the debate over the taxation of private equity and hedge fund managers. We provide an analytical model that allows us to compare the relative risk-reward benefit enjoyed by these fund managers and other managers. We look to "relative benefits" in order to determine the extent to which the current state of the world favors the services of a fund manager over these other workers. Our conclusion is that private equity and hedge fund managers do outperform other workers on a risk-adjusted, after-tax basis. We assume that over time compensation of private equity and …

Learning Policies For Embodied Virtual Agents Through Demonstration, Jonathan Dinerstein, Parris K. Egbert, Dan A. Ventura

Faculty Publications

Although many powerful AI and machine learning techniques exist, it remains difficult to quickly create AI for embodied virtual agents that produces visually lifelike behavior. This is important for applications (e.g., games, simulators, interactive displays) where an agent must behave in a manner that appears human-like. We present a novel technique for learning reactive policies that mimic demonstrated human behavior. The user demonstrates the desired behavior by dictating the agent’s actions during an interactive animation. Later, when the agent is to behave autonomously, the recorded data is generalized to form a continuous state-to-action mapping. Combined with an appropriate animation algorithm …

Sentiment Regression: Using Real-Valued Scores To Summarize Overall Document Sentiment, Adam Drake, Eric K. Ringger, Dan A. Ventura

Faculty Publications

In this paper, we consider a sentiment regression problem: summarizing the overall sentiment of a review with a real-valued score. Empirical results on a set of labeled reviews show that real-valued sentiment modeling is feasible, as several algorithms improve upon baseline performance. We also analyze performance as the granularity of the classification problem moves from two-class (positive vs. negative) towards infinite-class (real-valued).

Daily Forecasts Of Columbia River Plume Circulation: A Tale Of Spring/Summer Cruises, Yinglong J. Zhang, Antonio M. Baptista, Barbara M. Hickey, Byron C. Crump, David A. Jay, Michael Wilkin, Charles Seaton

Civil and Environmental Engineering Faculty Publications and Presentations

Semi-operational daily forecasts of circulation from an observatory for the Columbia River estuary-plume-shelf system routinely support oceanographic cruises, by providing 24h-ahead estimates of plume location and structure for planning purposes and for near real-time interpretation of observations. This paper analyzes forecast skill during spring/summer cruises in 2004-2007. Assessment addresses both qualitative descriptions of major plume trends and features and quantitative representation of data from (primarily) vessel-based flow-through, cast and towed systems. Forecasts emerge as robust predictors of plume location and variability, with skill that has grown over time, at least in part due to improvements in model algorithms. When the …

New Particle Formation In The Front Range Of The Colorado Rocky Mountains, Micahel Boy, Thomas Karl, Andrew Turnipseed, Roy Lee Mauldin, Edward Kosciuch, James Greenberg, Jeff Rathbone, James Smith, Andreas Held, Kelley Barsanti, Alex Guenther

Civil and Environmental Engineering Faculty Publications and Presentations

New particle formation is of interest because of its influence on the properties of aerosol population, and due to the possible contribution of newly formed particles to cloud condensation nuclei. Currently no conclusive evidence exists as to the mechanism or mechanisms of nucleation and subsequent particle growth. However, nucleation rates exhibit a clear dependence on ambient sulphuric acid concentrations and particle growth is often attributed to the condensation of organic vapours. A detailed study of new particle formation in the Front Range of the Colorado Rocky Mountains is presented here. Gas and particle measurement data for 32 days was analyzed …

Performance Comparison Of Pb(Zr0.52Ti0.48)O3-Only And Pb(Zr0.52Ti0.48)O3-On-Silicon Resonators, Hengky Chandrahalim, Sunil A. Bhave, Ronald G. Polcawich, Jeff Pulskamp, Dan Judy, Roger Kaul, Madan Dubey

Faculty Publications

This paper provides a quantitative comparison and explores the design space of lead zirconium titanate (PZT)–only and PZT-on-silicon length-extensional mode resonators for incorporation into radio frequency microelectromechanical system filters and oscillators. We experimentally measured the correlation of motional impedance (R_X) and quality factor (Q) with the resonators’ silicon layer thickness (t_Si). For identical lateral dimensions and PZT-layer thicknesses (t_PZT), the PZT-on-silicon resonator has higher resonant frequency (f_C), higher Q (5100 versus 140), lower R_X (51 Ω versus 205 Ω), and better linearity [third-order input intercept …

Review Of The American Society For Engineering Education (Asee) Global Colloquium, Cape Town, South Africa, Philip A. Reed

STEMPS Faculty Publications

The following report addresses topics established by the Technical Foundation of America prior to attending the ASEE Global Colloquium October 19-24, 2008 in Cape Town South Africa. Specifically, this manuscript will address what the international engineering education community and the technology education community might have to offer each other. Responses appear below each of the three categories: impacts on curriculum, professional development, and collaboration.

Factors Associated With Public School Chronic Absenteeism, Roger Herbert Antworth

UNF Graduate Theses and Dissertations

Chronic absenteeism is a problem that has plagued the public school system for a number of years. The cost of missed days of school can be counted in missed work, missed participation, and missed opportunities. The chronically absent student falls behind his/her peers academically which may lead to grade level retention and truancy. Truancy has been identified as one of the key indicators associated with students in public schools who drop out of school. Truancy can also be a predictor of illegal drug use by students (U.S. Department of Education, 2006).

Researchers have attempted to identify the various characteristics of …

Order Restricted Inference For Comparing The Cumulative Incidence Of A Competing Risk Over Several Populations, Hammou El Barmi, Subhash C. Kochar, Hari Mukerjee

Mathematics and Statistics Faculty Publications and Presentations

There is a substantial literature on testing for the equality of the cumulative incidence functions associated with one specific cause in a competing risks setting across several populations against specific or all alternatives. In this paper we propose an asymptotically distribution-free test when the alternative is that the incidence functions are linearly ordered, but not equal. The motivation stems from the fact that in many examples such a linear ordering seems reasonable intuitively and is borne out generally from empirical observations. These tests are more powerful when the ordering is justified. We also provide estimators of the incidence functions under …

Correction To "Stochastic Comparisons Of Parallel Systems When Components Have Proportional Hazard Rates", Subhash C. Kochar, Maochao Xu

Mathematics and Statistics Faculty Publications and Presentations

In the article "Stochastic comparisons of parallel systems when component have proportional hazard rates" we found a gap in the middle of the proof of Theorem 3.2. Therefore, we do not know whether Theorem 3.2 is true for the reverse hazard rate order. However, we could prove the following weaker result for the stochastic order.

Multigrid Convergence For Second Order Elliptic Problems With Smooth Complex Coefficients, Jay Gopalakrishnan, Joseph E. Pasciak

Mathematics and Statistics Faculty Publications and Presentations

The finite element method when applied to a second order partial differential equation in divergence form can generate operators that are neither Hermitian nor definite when the coefficient function is complex valued. For such problems, under a uniqueness assumption, we prove the continuous dependence of the exact solution and its finite element approximations on data provided that the coefficients are smooth and uniformly bounded away from zero. Then we show that a multigrid algorithm converges once the coarse mesh size is smaller than some fixed number, providing an efficient solver for computing discrete approximations. Numerical experiments, while confirming the theory, …

Polynomial Extension Operators. Part I, Leszek Demkowicz, Jay Gopalakrishnan, Joachim Schöberl

Mathematics and Statistics Faculty Publications and Presentations

In this series of papers, we construct operators that extend certain given functions on the boundary of a tetrahedron into the interior of the tetrahedron, with continuity properties in appropriate Sobolev norms. These extensions are novel in that they have certain polynomial preservation properties important in the analysis of high order finite elements. This part of the series is devoted to introducing our new technique for constructing the extensions, and its application to the case of polynomial extensions from H^½(∂K) into H¹(K), for any tetrahedron K.

Asymptotic And Numerical Techniques For Resonances Of Thin Photonic Structures, Jay Gopalakrishnan, Shari Moskow, Fadil Santosa

Mathematics and Statistics Faculty Publications and Presentations

We consider the problem of calculating resonance frequencies and radiative losses of an optical resonator. The optical resonator is in the form of a thin membrane with variable dielectric properties. This work provides two very different approaches for doing such calculations. The first is an asymptotic method which exploits the small thickness and high index of the membrane. We derive a limiting resonance problem as the thickness goes to zero, and for the case of a simple resonance, find a first order correction. The limiting problem and the correction are in one less space dimension, which can make the approach …

A Mixed Method For Axisymmetric Div-Curl Systems, Dylan M. Copeland, Jay Gopalakrishnan, Joseph E. Pasciak

Mathematics and Statistics Faculty Publications and Presentations

We present a mixed method for a three-dimensional axisymmetric div-curl system reduced to a two-dimensional computational domain via cylindrical coordinates. We show that when the meridian axisymmetric Maxwell problem is approximated by a mixed method using the lowest order Nédélec elements (for the vector variable) and linear elements (for the Lagrange multiplier), one obtains optimal error estimates in certain weighted Sobolev norms. The main ingredient of the analysis is a sequence of projectors in the weighted norms satisfying some commutativity properties.