Physical Sciences and Mathematics Commons^™

Jackknife Empirical Likelihood For The Accelerated Failure Time Model With Censored Data, Maxime K. Bouadoumou

Mathematics Theses

Kendall and Gehan estimating functions are used to estimate the regression parameter in accelerated failure time (AFT) model with censored observations. The accelerated failure time model is the preferred survival analysis method because it maintains a consistent association between the covariate and the survival time. The jackknife empirical likelihood method is used because it overcomes computation difficulty by circumventing the construction of the nonlinear constraint. Jackknife empirical likelihood turns the statistic of interest into a sample mean based on jackknife pseudo-values. U-statistic approach is used to construct the confidence intervals for the regression parameter. We conduct a simulation study …

Thermal-Initiated Hydroxyethyl Methacrylate Functionalization Of Multiwalled Carbon Nanotubes, Greg Curtzwiler, Philip Costanzo, Ray Fernando, Jeffrey E. Danes, Keith Vorst

Chemistry and Biochemistry

Multiwalled-carbon nanotubes (MWCNTs) were functionalized via thermoinitiated free radical polymerization of 2-hydroxyethyl methacrylate (HEMA) using benzoyl peroxide. Tip sonication was used during the polymerization reaction to separate agglomerated nanotubes. The functionalization was confirmed by control experiments and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). Differential scanning calorimetry indicated that the addition of poly(HEMA)-MWCNTs to a two-component polyurethane coating will have little effect on the glass transition temperature of the coating. The poly(HEMA)-functionalized MWCNTs formed large colloidal structures of highly dispersed nanotubes in both the nonsheared and sheared coatings as determined by atomic force microscopy. This study determined a quick …

Taxonomy And Geochemistry Of The Globigerinoides Ruber-Elongatus Plexus, With Paleontological Implications, Elizabeth Ann Brown

USF Tampa Graduate Theses and Dissertations

The reliability of foraminifera as stratigraphic index fossils, and as isotopic proxies of marine environments, is based on the assumption that the fossil concepts represent uniform species, responding consistently to their ambient environments. Understanding sources of uncertainty is, therefore, critical. In this dissertation, I explore a potential bias in the application of planktonic foraminifera utilized extensively for Cenozoic paleo-reconstruction and, to a lesser extent, biostratigraphy: the Globigerinoides ruber-elongatus plexus (‘plexus’ meaning a complex network of interconnected members). Taxonomic revisions since 1826 have resulted in the merging of multiple Globigerinoides species names under one general designation (“Globigerinoides ruber”), the implications of …

Exact Workspace Boundary By Extremal Reaches, Ciprian S. Borcea, Ileana Streinu

Computer Science: Faculty Publications

We present the first exact, combinatorial, polynomial time algorithm for computing the description of the workspace boundary for the class of revolute jointed robot arms arising from polygonal orthogonal chains in 3D. Copyright 2011 ACM.

Extremal Reaches In Polynomial Time, Ciprian S. Borcea, Ileana Streinu

Computer Science: Faculty Publications

Given a 3D polygonal chain with fixed edge lengths and fixed angles between consecutive edges (shortly, a revolutejointed chain or robot arm), the Extremal Reaches Problem asks for those configurations where the distance between the endpoints attains a global maximum or minimum value. In this paper, we solve it with a polynomial time algorithm. Copyright 2011 ACM.

Assessing Medicare Beneficiaries’ Strength‐Of‐Preference Scores For Health Care Options: How Engaging Does The Elicitation Technique Need To Be?, Trafford Crump, Hilary A. Llewellyn-Thomas

Dartmouth Scholarship

The objective was to determine if participants’ strength‐of‐preference scores for elective health care interventions at the end‐of‐life (EOL) elicited using a non‐engaging technique are affected by their prior use of an engaging elicitation technique.

Urban Climate And Challenges Of Tropical Cities, B E. Omogbai

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

This study examines the nature of urban climate, features and the challenges on the developing tropical cities in the 21st century. It argues that the use of principles of urban climate would help in providing comfortable living conditions and problem immune working environments for the inhabitants of tropical cities. The findings reveal that owing to poor environmental planning, inadequate geotechnical landscape surveys prior to the development of urban infrastructures, and non-adherence to the principles of urban climate, challenges of landscape degradation, excessive flooding of the built infrastructures, heat-island effects, and collapse of buildings have emerged. Suggested measures to avert these …

Prevalence Of Chronic Diseases And Risk Factors For Death Among Elderly Americans, Guangming Han

Mathematics Theses

The main aim of this study is to explore the effects of risk factors contributing to death in the elderly American population. To achieve this purpose, we constructed Cox proportional hazard regression models and logistic regression models with the complex survey dataset from the national Second Longitudinal Study of Aging (LSOA II) to calculate the hazard ratios (HR)/odds ratios (OR) and confidence interval (CI) of risk factors. Our results show that in addition to chronic disease conditions, many risk factors, such as demographic factors (gender and age), social factors (interaction with friends or relatives), personal health behaviors (smoking and exercise), …

Scuta: A Server-Side Access Control System For Web Applications, Xi Tan, Wenliang Du, Tongbo Luo, Karthick Jayaraman

Electrical Engineering and Computer Science - Technical Reports

The Web is playing a very important role in our lives, and is becoming an essential element of the computing infrastructure. Unfortunately, its importance makes it the preferred target of attacks. Web-based vulnerabilities now outnumber traditional computer security concerns. A recent study shows that over 80 percent of web sites have had at least one serious vulnerability. We believe that the Web’s problems, to a large degree, are caused by the inadequacy of its underlying access control systems. To reduce the number of vulnerabilities, it is essential to provide web applications with better access control models that can adequately address …

On Khovanov-Seidel Quiver Algebras And Bordered Floer Homology, Denis Auroux, J. Elisenda Grigsby, Stephan M. Wehrli

Mathematics - All Scholarship

We discuss a relationship between Khovanov- and Heegaard Floer-type homology theories for braids. Explicitly, we define a filtration on the bordered Heegaard-Floer homology bimodule associated to the double-branched cover of a braid and show that its associated graded bimodule is equivalent to a similar bimodule defined by Khovanov and Seidel.

Green Decarbonylation Of Aldehydes Using Palladium (Ii) Acetate, Jessica Konopka

Pell Scholars and Senior Theses

Decarbonylation reactions are important reactions in the chemical industry with typical methods being costly and wasteful. It is important to determine an effective catalyst and to see how general the reaction is with varying aldehydes, as well as to reduce the waste and make the reaction more cost effective. Several different aldehydes were studied using palladium (II) acetate as a catalyst. The samples were analyzed using Gas Chromatography Mass Spectroscopy (GC-MS) to determine if a product was formed based on the percent report obtained. Palladium (II) acetate was found to be an effective catalyst, yielding 100% product for several aldehydes …

The Electrochemical Detection Of Interleukin-8, Cancer Biomarker, Based On A Gold Nanoparticle Platform And Its Political Implications, Jaimee Doucette

Pell Scholars and Senior Theses

Herein we report on an ultrasensitive immunosensor based on glutathione protected gold nanoparticle (GSH-AuNP) for the electrochemical detection of interleukin 8 (IL-8), cancer biomarker in calf serum and proof of concept IL-8 detection in HNSCC cells. GSH-AuNP were bioconjugated to the primary antibodies (Ab1) and used to capture human IL-8 in a sandwich electrochemical immunoassay coupled to horseradish peroxidase enzyme labels. Using the optimized concentrations of the primary (Ab1) and secondary antibodies (Ab2), two sensor approaches were used to measure ultra low (≤ 500 fg mL-1) and elevated levels of IL-8. Biotinylated Ab2 bound to streptavidin HRP with 14-16 labels …

New Measurements Of Total Ionizing Dose In The Lunar Environment, J. E. Mazur, W. R. Crain, M. D. Looper, D. J. Mabry, J. B. Blake, A. W. Case, M. J. Golightly, J. C. Kasper, Harlan E. Spence

Physics & Astronomy

[1] We report new measurements of solar minimum ionizing radiation dose at the Moon onboard the Lunar Reconnaissance Orbiter (LRO) from June 2009 through May 2010. The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument on LRO houses a compact and highly precise microdosimeter whose design allows measurements of dose rates below 1 micro-Rad per second in silicon achieved with minimal resources (20 g, ∼250 milliwatts, and ∼3 bits/second). We envision the use of such a small yet accurate dosimeter in many future spaceflight applications where volume, mass, and power are highly constrained. As this was the first …

Nonlinear Hydrodynamics Of Disentangled Flux-Line Liquids, Panayotis Benetatos, M. Cristina Marchetti

Physics - All Scholarship

In this paper we use non-Gaussian hydrodynamics to study the magnetic response of a flux-line liquid in the mixed state of a type-II superconductor. Both the derivation of our model, which goes beyond conventional Gaussian flux liquid hydrodynamics, and its relationship to other approaches used in the literature are discussed. We focus on the response to a transverse tilting field which is controlled by the tilt modulus, c44, of the flux array. We show that interaction effects can enhance c44 even in infinitely thick clean materials. This enhancement can be interpreted as the appearance of a disentangled flux-liquid fraction. In …

Ejecta Knot Flickering, Mass Ablation, And Fragmentation In Cassiopeia A, Robert A. Fesen, Jordan A. Zastrow, Molly C. Hammell, J. Michael Shull, Devin W. Silvia

Dartmouth Scholarship

Ejecta knot flickering, ablation tails, and fragmentation are expected signatures associated with the gradual dissolution of high-velocity supernova (SN) ejecta caused by their passage through an inhomogeneous circumstellar medium or interstellar medium (ISM). Such phenomena mark the initial stages of the gradual merger of SN ejecta with and the enrichment of the surrounding ISM. Here we report on an investigation of this process through changes in the optical flux and morphology of several high-velocity ejecta knots located in the outskirts of the young core-collapse SN remnant Cassiopeia A using Hubble Space Telescope images. Examination of WFPC2 F675W and combined ACS …

The Vaporization Enthalpies Of 2- And 4-(N,N-Dimethylamino)Pyridine, 1,5-Diazabicyclo[4.3.0]Non-5-Ene, 1,8-Diazabicyclo[5.4.0]Undec-7-Ene, Imidazo[1,2-A]Pyridine And 1,2,4-Triazolo[1,5-A]Pyrimidine By Correlation-Gas Chromatography., Dmitry Lipkind, Nigam Rath, James S. Chickos, Vasiliy A. Pozdeev, Sergey P. Verevkin

James Chickos

No abstract provided.

Importance Of Soil Texture To Vineyard Management, Thomas J. Rice

Thomas J. Rice

No abstract provided.

How Do Environmental And Natural Resource Economics Texts Deal With The Simple Model Of The Intertemporal Allocation Of A Nonrenewable Resource, Robert Main

Robert S. Main

Textbooks in Environmental and Natural Resource Economics invariably deal with the problem of allocating a non-renewable resource over time. The simplest version of that problem is the case of a resource that is to be allocated over two periods. The resource has a constant Marginal Extraction Cost (MEC). Most textbooks treat this case before moving on to more complex and realistic cases. This paper suggests the results that should be emphasized and the method that should be used to arrive at those results. It also points out the possible confusions that should be avoided. Finally, it examines how several well-known …

Photodissociation Of N2O: Energy Partitioning, Johan A. Schmidt, M. S. Johnson, U. Lorenz, George C. Mcbane, Reinhard Schinke

Peer Reviewed Articles

The energy partitioning in the UV photodissociation of N₂O is investigated by means of quantum mechanical wave packet and classical trajectory calculations using recently calculated potential energy surfaces. Vibrational excitation of N₂ is weak at the onset of the absorption spectrum, but becomes stronger with increasing photon energy. Since the NNO equilibrium angles in the ground and the excited state differe by about 70°, the molecule experiences an extraordinarily large torque during fragmentation producing N₂in very high rotational states. The vibrational and rotational distributions obtained from the quantum mechanical and the classical calculations agree remarkably …

Evaluating And Implementing Web Scale Discovery Services: Part One, Jason Vaughan, Tamera Hanken

Library Faculty Presentations

Preface: Before Web Scale Discovery

• A very brief overview

Part 1: What is Web Scale Discovery

• Content
• Technology

Part 2: Why is Web Scale Discovery important?

• What’s the need?
• How is it different from earlier attempts at broad discovery?

Part 3: A Framework for Evaluating Web Scale Discovery Services

• What we did at UNLV
• Other options