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2007

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Articles 271 - 300 of 5729

Full-Text Articles in Physical Sciences and Mathematics

Friends Of The Uta Library Mcnair Scholarship Awards, The Mcnair Team Dec 2007

Friends Of The Uta Library Mcnair Scholarship Awards, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.


Study Of Multiple Impacts Of A Rigid Body With A Flat Surface, Florin Vasile Badiu Dec 2007

Study Of Multiple Impacts Of A Rigid Body With A Flat Surface, Florin Vasile Badiu

Mathematics Dissertations - Archive

Both analytical and numerical results are presented for two rigid body problems: a rod colliding with the ground, and a rigid thin plate colliding with the ground. The study of the succession of impacts of the rod with the ground confirms results from literature, and explores new cases. Numerical simulations can provide results in the study of the clattering impacts of a 3D body colliding with the ground. For a simplification of the analytical calculations, a rectangular plate without thickness is studied. In this case, a comparison between the numerical method, which is a continuous contact method, and the analytical …


The Global Stratotype Section And Point (Gssp) For The Base Of The Katian Stage Of The Upper Ordovician Series At Black Knob Ridge, Southeastern Oklahoma, Usa, Daniel Goldman, Stephen A. Leslie, Jaak Nõlvak, Seth Young, Stig M. Bergström, Warren D. Huff Dec 2007

The Global Stratotype Section And Point (Gssp) For The Base Of The Katian Stage Of The Upper Ordovician Series At Black Knob Ridge, Southeastern Oklahoma, Usa, Daniel Goldman, Stephen A. Leslie, Jaak Nõlvak, Seth Young, Stig M. Bergström, Warren D. Huff

Department of Earth, Environment and Sustainability Faculty Publications

The International Subcomission on Ordovician Stratigraphy (ISOS) of the International Commission on Stratigraphy (ICS) recently defined the base of the global Upper Ordovician Series to be at the first appearance datum (FAD) of the graptolite species Nemagraptus gracilis in the Fågelsång GSSP in southern Sweden. This designation recognized the tremendous utility for global correlation of the first appearance of a cosmopolitan taxon that occurs within a consistent succession of other first appearance datums (e.g., Finney and Bergström, 1986; Bergström et al., 2000). Current efforts by the ISOS have focused on subdividing the Upper Ordovician into three stages and choosing appropriate …


Structure And Excitations In Metal Ammonia Compounds, Xue Wang Dec 2007

Structure And Excitations In Metal Ammonia Compounds, Xue Wang

Dissertations

This work has two parts. In the first part, inelastic x-ray scattering was used to measure the plasmon excitations in liquid lithium ammonia systems. The measurements were carried out for different metal concentrations, 8 mole per metal (MPM), 10 MPM, 11 MPM, 16 MPM and 20 MPM of temperature 200K. The data were analyzed to determine the plasmon energy and the linewidth as a function of momentum for each metal concentration. Deviations from the random phase approximation (RPA) in the jellium model increase as the concentration is lowered.

In the second part of this work, elastic x-ray scattering was used …


What Is Rcu, Fundamentally?, Paul E. Mckenney, Jonathan Walpole Dec 2007

What Is Rcu, Fundamentally?, Paul E. Mckenney, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Read-copy update (RCU) is a synchronization mechanism that was added to the Linux kernel in October of 2002. RCU achieves scalability improvements by allowing reads to occur concurrently with updates. In contrast with conventional locking primitives that ensure mutual exclusion among concurrent threads regardless of whether they be readers or updaters, or with reader-writer locks that allow concurrent reads but not in the presence of updates, RCU supports concurrency between a single updater and multiple readers. RCU ensures that reads are coherent by maintaining multiple versions of objects and ensuring that they are not freed up until all pre-existing read-side …


A Random Change Of Variables And Applications To The Stochastic Porous Medium Equation With Multiplicative Time Noise, S V Lototsky Dec 2007

A Random Change Of Variables And Applications To The Stochastic Porous Medium Equation With Multiplicative Time Noise, S V Lototsky

Communications on Stochastic Analysis

No abstract provided.


Portfolio Optimization With Consumption In A Fractional Black-Scholes Market, Yalçin Sarol, Frederi G Viens, Tao Zhang Dec 2007

Portfolio Optimization With Consumption In A Fractional Black-Scholes Market, Yalçin Sarol, Frederi G Viens, Tao Zhang

Communications on Stochastic Analysis

No abstract provided.


Local Theorems Related To Lévy-Type Branching Mechanism, Vladimir Vinogradov Dec 2007

Local Theorems Related To Lévy-Type Branching Mechanism, Vladimir Vinogradov

Communications on Stochastic Analysis

No abstract provided.


Functional Limit Theorems For Trace Processes In A Dyson Brownian Motion, Victor Pérez-Abreu, Constantin Tudor Dec 2007

Functional Limit Theorems For Trace Processes In A Dyson Brownian Motion, Victor Pérez-Abreu, Constantin Tudor

Communications on Stochastic Analysis

No abstract provided.


Almost Any State Of Any Amplitude Markov Chain Is Recurrent, Luigi Accardi, Hiromichi Ohno Dec 2007

Almost Any State Of Any Amplitude Markov Chain Is Recurrent, Luigi Accardi, Hiromichi Ohno

Communications on Stochastic Analysis

No abstract provided.


Schrödinger Type Equation Associated With The Lévy And Volterra Laplacians, Kazuyoshi Sakabe Dec 2007

Schrödinger Type Equation Associated With The Lévy And Volterra Laplacians, Kazuyoshi Sakabe

Communications on Stochastic Analysis

No abstract provided.


Existence And Uniqueness Of Solutions To The Backward Stochastic Lorenz System, P Sundar, Hong Yin Dec 2007

Existence And Uniqueness Of Solutions To The Backward Stochastic Lorenz System, P Sundar, Hong Yin

Communications on Stochastic Analysis

No abstract provided.


The Characterization Of A Class Of Probability Measures By Multiplicative Renormalization, Izumi Kubo, Hui-Hsiung Kuo, Suat Namli Dec 2007

The Characterization Of A Class Of Probability Measures By Multiplicative Renormalization, Izumi Kubo, Hui-Hsiung Kuo, Suat Namli

Communications on Stochastic Analysis

No abstract provided.


Synthesis, Study Of Self-Assembly, And Trivalent Lanthanide Metal Ion Recognition Characteristics Of Amphiphilic Acylpyrazolones And Amphiphilic Acylisoxazolones, Venkat Reddy Guduru Dec 2007

Synthesis, Study Of Self-Assembly, And Trivalent Lanthanide Metal Ion Recognition Characteristics Of Amphiphilic Acylpyrazolones And Amphiphilic Acylisoxazolones, Venkat Reddy Guduru

Dissertations

This research project focused on the separation of trivalent lanthanide metal ions by HPLC using amphiphilic acylpyrazolones and amphiphilic acylisoxazolones. The central hypothesis of our research project is that the nanoscale self-assembly nature of amphiphilic ligands (chelating lingads) can influence their metal ion recognition and separation. To test the central hypothesis, we have synthesized a family of novel amphiphilic ligands and employed them as model systems for the separation of trivalent lanthanide metal ions. Several novel intermediates such as 4-acylated. N -acylated, O -acylated pyrazolones and isoxazolones, have been efficiently synthesized and fully characterized.*

The trivalent lanthanide metal ion recognition …


Diagnostics For Choosing Between Log-Rank And Wilcoxon Tests, Ruvie Lou Maria Custodio Martinez Dec 2007

Diagnostics For Choosing Between Log-Rank And Wilcoxon Tests, Ruvie Lou Maria Custodio Martinez

Dissertations

Two commonly used tests for comparison of survival curves are the generalized Wilcoxon procedure of Gehan (1965) and Breslow (1970) and the Log-rank test proposed by Mantel (1966) and Cox (1972). In applications, the Log-rank test is used after checking for validity of the proportional hazards (PH) assumption, with Wilcoxon being the fallback method when the PH assumption fails.

However, the relative performance of the two procedures depend not just on the PH assumption but also on the pattern of differences between the two curves. We will show that the crucial factor is whether the differences tend to occur early …


Adsorption Of Lead On Single And Mixed Solid Systems, Soumya Das Dec 2007

Adsorption Of Lead On Single And Mixed Solid Systems, Soumya Das

Dissertations

Metal oxy-hydroxides and phyllosilicate minerals play a significant role in the fate and transport of heavy metals in the environment (Bertsch and Seaman, 1999). Chemical speciation of metals affects their bioavailability and chemical reactivity (Stumm and Morgan, 1996). Surface complexation models (SCMs) based on equilibrium thermodynamic principles have been successfully used to quantify adsorption of heavy metals on pure solid minerals, including phyllosilicates and oxy-hydroxides. For natural sediments with mixed mineralogy, Davis et al. (1998) suggested two different SCM approaches, namely, the component additivity and generalized composite models. In this study, adsorption of lead on pure HFO, silica and kaolinite …


Quantum Properties Of Light Emitted By Dipole Nano-Laser, Talal Ghannam Dec 2007

Quantum Properties Of Light Emitted By Dipole Nano-Laser, Talal Ghannam

Dissertations

Recent technological advances allow entire optical systems to be lithographically implanted on small silicon chips. These systems include tiny semiconductor lasers that function as light sources for digital optical signals. Future advances will rely on even smaller components. At the theoretical limit of this process, the smallest lasers will have an active medium consisting of a single atom (natural or artificial). Several suggestions for how this can be accomplished have already been published, such as nano-lasers based on photonic crystals and nano wires. In particular, the "dipole nanolaser" consists of a single quantum dot functioning as the active medium. It …


Synthesis And Characterization Of Stilbenoids And Their Aza-Analogs As Photoluminescent Materials For The Detection Of Nerve Agent Mimics, Chun Wang Dec 2007

Synthesis And Characterization Of Stilbenoids And Their Aza-Analogs As Photoluminescent Materials For The Detection Of Nerve Agent Mimics, Chun Wang

Dissertations

A novel series of stilbenoids and their aza analogs were synthesized, characterized and used as photoluminescent components in the detection of nerve agents. Their structure-property relationship was elucidated through UV-visible and fluorescence spectroscopy. The research in this thesis is driven by the hypothesis that the two-block sensor system consisting of a receptor incorporated ruthenium complex and a fluorescent signal molecule of stilbenoids, is capable of detecting chemical warfare agents. The sensor anchored onto nanoparticles and subsequently the nanoparticles were arranged through mediated self-assembly. While photo-induced electron transfer is a well-known mechanism for sensor design, the described system showed that photo-induced …


Efficacy Of Cognitive Therapy And Pharmacotherapy In Depression: A Meta-Analysis, Daniel B. Michel Dec 2007

Efficacy Of Cognitive Therapy And Pharmacotherapy In Depression: A Meta-Analysis, Daniel B. Michel

Loma Linda University Electronic Theses, Dissertations & Projects

A meta-analysis comparing the long-term effectiveness of cognitive behavioral therapy (CBT) and pharmacotherapy in preventing relapse following treatment discontinuation was performed using published studies of depressed participants. Twenty-three articles met inclusionary criteria and were included in the analyses. Weighted effect sizes and moderators, treatment type, were calculated using statistical analysis software. Initially, fixed effects models were applied to the data, but due to significant between-group heterogeneity that could not be fully explained by treatment type, mixed effect models were used to account for the residual heterogeneity. Results indicated that overall, depressed individuals treated to remission with CBT evidence decreased relapse …


On The Total Duration Of Negative Surplus Of A Risk Process With Two-Step Premium Function, Pavlina Jordanova Dec 2007

On The Total Duration Of Negative Surplus Of A Risk Process With Two-Step Premium Function, Pavlina Jordanova

Applications and Applied Mathematics: An International Journal (AAM)

We consider a risk reserve process whose premium rate reduces from cd to cu when the reserve comes above some critical value v. In the model of Cramer-Lundberg with initial capital u ≥ 0, we obtain the probability that ruin does not occur before the first up-crossing of level v. When u < v, following H. Gerber and E. Shiu (1997), we derive the probability that starting with initial capital u ruin occurs and the severity of ruin is not bigger than v. Further we express the probability of ruin in the two step premium function model - ψ (u,v), by the last two probabilities. Our assumptions imply that the surplus process will go to infinity almost surely. This entails that the process will stay below zero only temporarily. We derive the distribution of the total duration of negative surplus and obtain its Laplace transform and mean value. As a consequence of these results, under certain conditions in the Model of Cramer-Lundberg we obtain the expected value of the severity of ruin. In the end of the paper we give examples with exponential claim sizes.


The Pcor Partnership – Building On Successful Regional, National, And International Partnerships, University Of North Dakota. Energy And Environmental Research Center Dec 2007

The Pcor Partnership – Building On Successful Regional, National, And International Partnerships, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about the Plains CO2 Reduction (PCOR) Partnership. The PCOR Partnership supports regional research to advance safe and effective CO2 storage. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]


Time-Adaptive Numerical Simulation For High Speed Networks, Suman Kumar, Seung Jong Park, S. Sitharama Iyengar, Jung Han Kimn Dec 2007

Time-Adaptive Numerical Simulation For High Speed Networks, Suman Kumar, Seung Jong Park, S. Sitharama Iyengar, Jung Han Kimn

Computer Science Faculty Research & Creative Works

As the bandwidth of networks is increasing exponentially, the computational cost to simulate such type of networks is also growing in a similar fashion. This paper presents a scalable simulation method, called time-adaptive numerical simulation, which can be used to represent dynamics of high-speed networks using fluid-based models. The new method dynamically adjusts the size of a time step for a numerical solver which solves a system of differential equations representing dynamics of protocols and nodes' behaviors. The simulation results show that the time-adaptive-method reduces the computational time while achieving the same accuracy compared to that of a fixed step-size …


Research Issues And Overview Of Economic Models In Mobile-P2p Networks, Anirban Mondal, Sanjay Kumar Madria, Masaru Kitsuregawa Dec 2007

Research Issues And Overview Of Economic Models In Mobile-P2p Networks, Anirban Mondal, Sanjay Kumar Madria, Masaru Kitsuregawa

Computer Science Faculty Research & Creative Works

The mobile-P2P paradigm is becoming increasingly popular. Existing mobile-P2P solutions largely do not consider economic incentive models for enticing peer participation without eliminating free-riders and for effectively handling mobile resource constraints such as energy. This paper presents an executive summary of the existing solutions and an overview of some of the important issues for handling problems in mobile-P2P networks using economic models. We also present our perspectives on building 'real' mobile-P2P applications using economic models. © 2007 IEEE.


Enlightened Computing: An Architecture For Co-Allocating Network, Compute, And Other Grid Resources For High-End Applications, Lina Battestilli, Andrei Hutanut, Gigi Karmous-Edwards, Daniel S. Katz, Jon Maclarent, Joe Mambretti, John H. Moore, Seung Jong Park, Harry G. Perros, Syam Sundar, Savera Tanwir, Steven R. Thorpe, Yufeng Xin Dec 2007

Enlightened Computing: An Architecture For Co-Allocating Network, Compute, And Other Grid Resources For High-End Applications, Lina Battestilli, Andrei Hutanut, Gigi Karmous-Edwards, Daniel S. Katz, Jon Maclarent, Joe Mambretti, John H. Moore, Seung Jong Park, Harry G. Perros, Syam Sundar, Savera Tanwir, Steven R. Thorpe, Yufeng Xin

Computer Science Faculty Research & Creative Works

Many emerging high-performance applications require distributed infrastructure that is significantly more powerful and flexible than traditional Grids. Such applications require the optimization, close integration, and control of all Grid resources, including networks. The EnLIGHTened (ENL) Computing Project has designed an architectural framework that allows Grid applications to dynamically request (in-advance or on-demand) any type of Grid resource: computers, storage, instruments, and deterministic, high-bandwidth network paths, including lightpaths. Based on application requirements, the ENL middleware communicates with Grid resource managers and, when availability is verified, co-allocates all the necessary resources. ENL's Domain Network Manager controls all network resource allocations to dynamically …


I’M A Virus Harming The Earth, M. Thulasidas Dec 2007

I’M A Virus Harming The Earth, M. Thulasidas

Research Collection School Of Computing and Information Systems

We humans plunder the raw material from our host planet with such an abandon that is only seen in viruses.


Fabrication Of Robust Superconducting Granular Aluminium/Palladium Bilayer Microbolometers With Sub-Nanosecond Response, Thomas E. Wilson Dec 2007

Fabrication Of Robust Superconducting Granular Aluminium/Palladium Bilayer Microbolometers With Sub-Nanosecond Response, Thomas E. Wilson

Physics Faculty Research

We provide a convenient recipe for fabricating reliable superconducting microbolometers as acoustic phonon detectors with sub-nanosecond response, using imagereversal optical lithography and dc-magnetron sputtering, and our recipe requires no chemical or plasma etching. Our approach solves the traditional problem for granular aluminium bolometers of unreliable (i.e., non-Ohmic) electrical contacts by sequentially sputtering the granular aluminium film and then a palladium capping layer. We use dc calibration data, the method of Danilchenko et al. [1], and direct nanosecond-pulsed photoexcitation to obtain the microbolometer’s characteristic current, thermal conductance, characteristic relaxation time, and heat capacity. We also demonstrate the use of the deconvolution …


Seasonal Changes In Thermal Conductance Of Bat Pelage: A Comparison Of The Eastern Red Bat (Lasiurus Borealis) And Big Brown Bat (Eptesicus Fuscus), Daniel Justin Judy Dec 2007

Seasonal Changes In Thermal Conductance Of Bat Pelage: A Comparison Of The Eastern Red Bat (Lasiurus Borealis) And Big Brown Bat (Eptesicus Fuscus), Daniel Justin Judy

All-Inclusive List of Electronic Theses and Dissertations

Two species with different ecologies and natural histories use different morphological characteristics and thermoregulatory strategies to survive seasonal environmental changes. The purpose of this project was to investigate two such species, the eastern red bat (Lasiurus borealis) and big brown bat (Eptesicus fuscus). Red bats roost in the foliage of trees and occasionally leaf litter and have dense fur, as well as a furred interfemoral membrane. These two species differ in their morphology and roosting ecology in that big brown bats are generally larger with less dense fur, no fur on the interfemoral membrane, and are less exposed to environmental …


The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2007, David J. Lauten, Kathleen J. Castelein, Raya Pruner, Marvin Friel, Eleanor P. Gaines Dec 2007

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2007, David J. Lauten, Kathleen J. Castelein, Raya Pruner, Marvin Friel, Eleanor P. Gaines

Institute for Natural Resources Publications

From 3 April – 21 September 2007, we monitored the distribution, abundance and productivity of the federally Threatened Western Snowy Plover (Charadrius alexandrinus nivosus) along the Oregon coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Beach, and New River. Our objectives for the Oregon coastal population in 2007 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) continue selected use of mini-exclosures (MEs) to protect nests from predators …


Prey Naiveté: Evolutionary And Ecological Implications, Jonathan G. Cox Dec 2007

Prey Naiveté: Evolutionary And Ecological Implications, Jonathan G. Cox

All-Inclusive List of Electronic Theses and Dissertations

Despite its ecological importance, the concept of prey naivete has become a biological truism that receives little study. I explored the evolution of naivete and its likely influence on two major ecological patterns: a) the historically greater destructiveness of freshwater predator introductions, and b) the greater strength of aquatic trophic cascades. In a review of the ecological literature, I demonstrate that the conditions for the evolution of naivete (isolation) exist in freshwater habitats at multiple spatial scales. In addition, I show that freshwater prey exhibit naivete which could be responsible for the high impacts of freshwater predator introductions. I then …


The Development Of A Quality Risk Management Solution Designed To Facilitate Compliance With The Risk-Based Qualification, Validation And Change Control Gmp Requirement Of The Eu, Kevin O'Donnell Dec 2007

The Development Of A Quality Risk Management Solution Designed To Facilitate Compliance With The Risk-Based Qualification, Validation And Change Control Gmp Requirement Of The Eu, Kevin O'Donnell

Doctoral

This research work was concerned with investigating the risk-based regulatory requirements that are currently in place in the European Union governing the manufacture of medicinal products. The main goal of this research was to develop a practical Quality Risk Management methodology that served as a solution for facilitating compliance with the EU GMP requirements in the area of risk-based Qualification, Validation and Change Control, and which was fully in line with the principles and guidance of ICH Q9, on Quality Risk Management. Following extensive testing and evaluation activities with a range of key stakeholders including the pharmaceutical manufacturing sector in …