Physical Sciences and Mathematics Commons^™

Electron Diffraction Study Of The Structure Of Vinylidene Fluoride–Trifluoroethylene Copolymer Nanocrystals, Mengjun Bai, Xingzhong Li, Stephen Ducharme

Stephen Ducharme Publications

The structures of nanocrystals consisting of 70% vinylidene fluoride and 30% trifluoroethylene made by Langmuir–Blodgett deposition were studied using transmission electron microscopy and electron diffraction. Highly ordered nanocrystals with sizes ranging from 100 nm to 4 μm were grown on Langmuir– Blodgett films at a deposition surface pressure of 20 mN m^-1. Electron diffraction patterns from individual crystals allowed us to determine the crystal symmetry and lattice parameters. A monoclinic phase had been found with the lattice parameters a = 9.06 ± 0.03 Å, b = 5.18 ± 0.02 Å, c = 20.40 ± 0.05 Å, α = …

Reliable Structures And Energetics For Two New Delocalized Π⋯Π Prototypes: Cyanogen Dimer And Diacetylene Dimer, Brian W. Hopkins, Adel M. Elsohly, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

Two new prototypes delocalized π⋯π complexes are introduced: the dimers of cyanogen, (N≡C-C≡N)2, and diacetylene, (HC≡C-C≡CH)2. These dimers have properties similar to larger delocalized π⋯π systems such as benzene dimer but are small enough that they can be probed in far greater detail with high accuracy electronic structure methods. Parallel-slipped and T-shaped structures of both cyanogen dimer and diacetylene dimer have been optimized with 15 different procedures. The effects of basis set size, theoretical method, counterpoise correction, and the rigid monomer approximation on the structure and energetics of each dimer have been examined. MP2 and CCSD(T) optimized geometries for all …

The Evolution Of Internet Legal Regulation In Addressing Crime And Terrorism, Murdoch Watney

Annual ADFSL Conference on Digital Forensics, Security and Law

Internet regulation has evolved from self-regulation to the criminalization of conduct to state control of information available, accessed and submitted. Criticism has been leveled at the different forms of state control and the methods employed to enforce state control. After the terrorist attack on the USA on 11 September 2001, governments justify Internet state control as a law enforcement and national security tool against the abuse and misuse of the Internet for the commission of serious crimes, such as phishing, child pornography; terrorism and copyright infringement. Some Internet users and civil rights groups perceive state control as an abomination which …

Molecular Hydrogen Formation On Amorphous Silicates Under Interstellar Conditions, Gianfranco Vidali, Hagai B. Perets, Ling Li, S. Swords, E. Congiu

Physics - All Scholarship

Experimental results on the formation of molecular hydrogen on amorphous silicate surfaces are presented for the first time and analyzed using a rate equation model. The energy barriers for the relevant diffusion and desorption processes are obtained. They turn out to be significantly higher than those obtained earlier for polycrystalline silicates, demonstrating the importance of grain morphology. Using these barriers we evaluate the efficiency of molecular hydrogen formation on amorphous silicate grains under interstellar conditions. It is found that unlike polycrystalline silicates, amorphous silicate grains are efficient catalysts of H_{2} formation within a temperature range which is relevant to diffuse …

Semantic Web Applications In Industry, Government, Health Care And Life Sciences, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

Irreducible Polynomials And Factorization Properties Of The Ring Of Integer-Valued Polynomials, Megan Gallant

Math Honors Theses

No abstract provided.

Cellular Planets: Optimizing Planetary Simulations For The Cell Processor, Brent Peckham

Computer Science Honors Theses

The Cell Broadband Engine is the first version of a new type of microprocessor developed jointly between IBM, Toshiba and Sony. The Cell is a multiprocessor that contains nine separate processors that all operate on a shared main memory. This thesis alters C code of planetary simulations that use numeric integrators with gravity as the inter-particle force, and optimizing the simulations to run on the Cell processor so the chip’s power can be harnessed. These optimizations are benchmarked and compared to one another in order to see what is necessary to get the most out of the Cell processor. In …

Investigation Of Novel Microseparation Techniques, Yansheng Liu

Theses and Dissertations

Ultrahigh pressure liquid chromatography (UHPLC) makes it possible to use very small particles (< 2 µm) as packing materials to provide high column efficiencies. Results from a careful comparison of small porous and nonporous particles show that when the particle size is small enough (< 2 µm), both porous and nonporous particles give excellent performance, and the differences in column efficiencies between porous and nonporous particles become insignificant. Columns packed with bare diamond particles could separate small molecules, especially polar molecules, however, severe tailing occurred for less polar compounds. The polybutadiene coated diamond particles gave greater retention and better separation of small molecules compared to bare particles, although no improvement in column efficiency was observed. Changes in surface bonding of thermally hydrogenated diamond particles was achieved by chemical modification using various organic peroxides with or without reagents containing long carbon chain functional groups. It appears that the alkyl groups were attached onto the diamond surface with limited coverage. LC experiments did not demonstrate good separation; however, changes in LC behavior were observed. A repetitive solvent programming approach was successfully applied to the analysis of a continuous sample stream in microbore LC. Each analysis cycle consisted of three steps: pseudo-injection, elution and rinse. In the pseudo-injection step, elution with a non- or poor-eluting solvent produced a concentrated sample plug due to on-column focusing. Factors influencing peak symmetry, resolution and analysis cycle length were investigated. Quantitative analysis of a continuous sample stream is possible under certain operating conditions. Electric field gradient focusing (EFGF) devices with distributed resistor substrates could focus proteins in the separation channel, however, the focused bands were not stable, and the repeatability was poor due to the formation of bubbles and pH gradient in the separation channel. Both fiber-based and porous glass capillary-based planar EFGF devices with changing cross-sectional area (CCSA) channels were constructed and evaluated with the aid of a home-made scanning laser-induced fluorescence detection system. The fiber-based CCSA EFGF devices gave poorer performance compared with glass capillary based devices. Porous glass capillary-based EFGF devices could focus single proteins and separate mixtures of two to three proteins.

Dialogue Television: The Climate Engineers, James Fleming

James R. Fleming

The problem of global warming is getting massive public attention. This comes forty years after the first major government report outlining the problem. But there is considerable disagreement over what steps should be taken to mitigate the problem and some scientist fear that politicians are not displaying sufficient urgency. James Fleming describes the technological quick fixes proposed by some scientists and the problems they might create.

Computation Of Correlation Functions And Wave Function Projections In The Context Of Quantum Trajectory Dynamics, Sophya Garashchuk

Faculty Publications

The de Broglie-Bohm formulation of the Schrödinger equation implies conservation of the wave function probability density associated with each quantum trajectory in closed systems. This conservation property greatly simplifies numerical implementations of the quantum trajectory dynamics and increases its accuracy. The reconstruction of a wave function, however, becomes expensive or inaccurate as it requires fitting or interpolation procedures. In this paper we present a method of computing wave packet correlation functions and wave function projections, which typically contain all the desired information about dynamics, without the full knowledge of the wave function by making quadratic expansions of the wave function …

Electrospray Ionization Applied To C60 And Carbon Nanotubes, Joshua V. Cardenzana

Opportunities for Undergraduate Research Experience Program (OURE)

An apparatus has been developed with the intent to produce beams consisting of C₆₀ and Single Walled Carbon Nanotubes (SWCNTs) by using Electrospray Ionization. Although Electrospray Ionization is commonly used for producing beams of large biomolecules, this technique has not been attempted before for producing Fullerene beams.

Through the process of Electrospray Ionization, beams consisting of C₆₀, and Single Walled Carbon Nanotubes (SWCNTs) can be obtained and measured using electrometers. Utilizing these measurements various alterations have been done to maximize the intensity of these beams. Many more minor and major additions are planned to improve the sensitivity …

Brown Tree Snake Technical Meetings

Other Publications in Wildlife Management

This is a preliminary announcement for the annual Brown Tree Snake working group Technical Meetings. These meetings are scheduled to occur between the 17th and 20th of April (a Tuesday through Friday). This meeting is open to the general public and interested parties.

The format of this meeting will be different from the previous brown tree snake working group technical meetings and participation is anticipated to be greater than the previous meetings. We currently have reserved space for up to 140 people at the Guam Hilton for the first day of the meeting. It is anticipated that attendance will be …

Mpscm: A Distributed Extension To Mzscheme, Alexander Starche

Computer Science Honors Theses

MPSCM is an extension to the MzScheme dialect of Scheme that provides facilities for distributed programming with a message passing base and higher-level distributing constructs designed in a more functional style. This paper provides a desciption of the MPSCM environment and an analysis of the results in terms of performance, expressivity, and usability.

Superluminal Motion In The Lobe-Dominated Quasars 3c207 And 3c245, Eric Danielson

Physics & Astronomy Honors Theses

We are conducting a Very Long Baseline Interferometer (VLBI) survey of a complete sample of 25 lobe-dominated quasars, with the goal of testing relativistic jet models. Since the quasars 3C207 and 3C245 have the most prominent parsec-scale jets, we have observed them intensively with the Very Long Baseline Array (VLBA) from 2003 to 2005 at 15 and 22 GHz. Data from observations made of 3C245 at 22 GHz were not usable due to the weak flux density of the source. We find superluminal motion in 3C207 when observing at 15 GHz, increasing from 2 to 3 times the speed of …

Hop-By-Hop Transport Control For Multi-Hop Wireless Networks, Daniel N. Scofield

Theses and Dissertations

TCP can perform poorly in multi-hop wireless networks due to problems with contention and poor feedback from end-to-end control algorithms. This thesis explores the design of a hop-by-hop transport protocol (HxH). By allowing intermediate nodes to actively participate, the protocol can respond more quickly to changing network conditions and exploit the unique characteristics of wireless networks. Results indicate that hop-by-hop transport can achieve throughput rates that are double those of TCP, depending on the speed of the wireless links.

T-Spline Simplification, David L. Cardon

Theses and Dissertations

This work focuses on generating approximations of complex T-spline surfaces with similar but less complex T-splines. Two approaches to simplifying T-splines are proposed: a bottom-up approach that iteratively refines an over-simple T-spline to approximate a complex one, and a top-down approach that evaluates existing control points for removal in producing an approximations. This thesis develops and compares the two simplification methods, determining the simplification tasks to which each is best suited. In addition, this thesis documents supporting developments made to T-spline research as simplification was developed.

Systematic Errors In Cosmic Microwave Background Interferometry, Emory F. Bunn

Physics Faculty Publications

Cosmic microwave background (CMB) polarization observations will require superb control of systematic errors in order to achieve their full scientific potential, particularly in the case of attempts to detect the B modes that may provide a window on inflation. Interferometry may be a promising way to achieve these goals. This paper presents a formalism for characterizing the effects of a variety of systematic errors on interferometric CMB polarization observations, with particular emphasis on estimates of the B-mode power spectrum. The most severe errors are those that couple the temperature anisotropy signal to polarization; such errors include cross talk within …

Detecting People In Images: An Edge Density Approach, Son Lam Phung, A. Bouzerdoum

Faculty of Informatics - Papers (Archive)

In this paper, we present a new method for detecting visual objects in digital images and video. The novelty of the proposed method is that it differentiates objects from non-objects using image edge characteristics. Our approach is based on a fast object detection method developed by Viola and Jones. While Viola and Jones use Harr-like features, we propose a new image feature - the edge density - that can be computed more efficiently. When applied to the problem of detecting people and pedestrians in images, the new feature shows a very good discriminative capability compared to the Harr-like features.

Principles And Analysis Of The Squeezing Approach To Low Bit Rate Spatial Audio Coding, B. Cheng, C. H. Ritz, I. Burnett

Faculty of Informatics - Papers (Archive)

This paper presents a novel solution to multichannel spatial audio coding: spatial squeezing surround audio coding (S³AC). The S³AC scheme analyses a multichannel audio signal and downmixes it into a stereo signal pair containing both the monophonic properties of audio sources and their localization information; this avoids the need for side information. The approach uses time-frequency analysis of a spatial audio scene and exploits virtual sources and amplitude panning techniques to 'squeeze' 360deg of a horizontal soundfield to a 60deg stereo signal pair. In comparison with other spatial audio coding techniques, S³AC significantly advances …

1,3-Bi-9-Anthrylpropane, Mustafa Arslan, Erol Asker, John Masnovi, Ronald J. Baker

Chemistry Faculty Publications

The title compound, C₃₁H₂₄, with three molecules in the asymmetric unit. The crystal packing is mainly stabilized by weak C—H⋯π inter­actions in addition to van der Waals forces.

Factors Contributing To Dust Emissions In Clark County, Nevada Quarterly Progress Report: Period Ending April 15, 2007, Margaret N. Rees

Dust Emissions from Public Lands

• Post-doctoral scholar commenced work
• Discussions with BLM personnel and site assessment necessitate additional project funds through Task Agreement Modification

Factors Contributing To Dust Emissions In Clark County, Nevada Quarterly Progress Report 2: Period Ending April 15, 2007, Margaret N. Rees

Dust Emissions from Public Lands

• Post-doctoral scholar commenced work
• Discussions with BLM personnel and site assessment necessitate additional project funds through Task Agreement Modification
• Preliminary Fieldwork and data collection initiated.

Monitoring Relative Abundance Of American Shad In Virginia Rivers 2006 Annual Report, John E. Olney, Kristen Delano Walter

Reports

Concern about the decline in landings of American shad (Alosa sapidissima) along the Atlantic coast prompted the development of an interstate fisheries management plan (FMP) under the auspices of the Atlantic States Marine Fisheries Management Program (ASMFC 1999). Legislation enables imposition of federal sanctions on fishing in those states that fail to comply with the FMP. To be in compliance, coastal states are required to implement and maintain fishery-dependent and fishery-independent monitoring programs as specified by the FMP. For Virginia, these requirements include spawning stock assessments, the collection of biological data on the spawning run (e.g., age-structure, sex ratio, and …

Squares Of Characters And Finite Groups, Edith Adan-Bante

Faculty Publications

Let G be a finite group and χ be an irreducible complex character. We study the character χ² in the case that χ(1) is a prime power.

Ua66 2007 Student Awards Ceremony, Wku Ogden College Of Science & Engineering

WKU Administration Documents

Program recognizing Ogden College students with brief list of activities for each student.

Optically Induced Suppression Of Spin Relaxation In Two-Dimensional Electron Systems With Rashba Interaction, Yuriy V. Pershin Dr

Faculty Publications

A pulsed technique for electrons in two-dimensional systems, in some ways analogous to spin echo in nuclear magnetic resonance, is discussed. We show that a sequence of optical below-band-gap pulses can be used to suppress the electron spin relaxation due to the D’yakonov-Perel’ spin relaxation mechanism. The spin relaxation time is calculated for several pulse sequences within a Monte Carlo simulation scheme. The maximum of the spin relaxation time as a function of magnitude or width of the pulses corresponds to a π pulse. It is important that even relatively distant pulses efficiently suppress spin relaxation.

Design And Implementation Of An Online Bath And Body Products Business, Norma Prince

Regis University Student Publications (comprehensive collection)

This project created an online extension of a bath and body products business. Currently, the author's son owns a business that provides soap and lip balm to brick-andmortar businesses. The products have been well accepted in the marketplace and an online venture was the next logical step to increase market share. For this project, a website was created that serves as an online storefront and product catalog. A traditional phased project management approach was used to complete the project. The analysis phase consisted of research into competitive companies as well as how to successfully design and implement an interactive website. …

Measurement Of The Charge Asymmetry In Semileptonic BS0 Decays, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collboration

Kenneth Bloom Publications

We have performed the first direct measurement of the time-integrated flavor untagged charge asymmetry in semileptonic B_s⁰ decays A_SL^s,unit by comparing the decay rate of B_s⁰ →μ⁺D_s^- νX, where D_s^-→ φ π^- and φ → K⁺K^-, with the charge-conjugate B̅_s⁰ decay rate. This sample was selected from 1.3 fb^-1 of data collected by the D0 experiment in run II of the Fermilab Tevatron collider. We obtain A_SL^s,unit= [1.23 ± 0.97(stat) ± 0.17(syst)] …

Linking Flux Network Measurements To Continental Scale Simulations: Ecosystem Carbon Dioxide Exchange Capacity Under Non-Water-Stressed Conditions, Katherine B. Owen, John Tenhunen, Markus Reichstein, Quan Wang, Eva Falge, Ralf Geyer, Xiangming Xiaos, Paul Stoy, Christof Ammann, Altaf Arain, Marc Aubinet, Mika Aurela, Christian Bernhofer, Bogdan Chojnicki, Andre Granier, Thomas Gruenwald, Julian Hadley, Bernard Heinesch, David Hollinger, Alexander Knohl, Werner Kutsch, Annalea Lohila, Tilden Meyers, Eddy Moors, Christine Moureaux, Kim Pilegaard, Nobuko Saigusa, Shashi Verma, Timo Vesala, Chris Vogel

School of Natural Resources: Faculty Publications

This paper examines long-term eddy covariance data from 18 European and 17 North American and Asian forest, wetland, tundra, grassland, and cropland sites under nonwater- stressed conditions with an empirical rectangular hyperbolic light response model and a single layer two light-class carboxylase-based model. Relationships according to ecosystem functional type are demonstrated between empirical and physiological parameters, suggesting linkages between easily estimated parameters and those with greater potential for process interpretation. Relatively sparse documentation of leaf area index dynamics at flux tower sites is found to be a major difficulty in model inversion and flux interpretation. Therefore, a simplification of the …

A Bayesian Hierarchical Framework For Spatial Modeling Of Fmri Data, F. Dubois Bowman, Brian S. Caffo, Susan Spear Bassett, Clinton Kilts

Johns Hopkins University, Dept. of Biostatistics Working Papers

Functional neuroimaging techniques enable investigations into the neural basis of human cognition, emotions, and behaviors. In practice, applications of functional magnetic resonance imaging (fMRI) have provided novel insights into the neuropathophysiology of major psychiatric,neurological, and substance abuse disorders, as well as into the neural responses to their treatments. Modern activation studies often compare localized task-induced changes in brain activity between experimental groups. One may also extend voxel-level analyses by simultaneously considering the ensemble of voxels constituting an anatomically defined region of interest (ROI) or by considering means or quantiles of the ROI. In this work we present a Bayesian extension …