Physical Sciences and Mathematics Commons^™

Neutron Scattering From Aerosols: Intraparticle Structure Factor, Guinier Analysis Of Particle Speed, And Crossed Beam Kinematics, Gerald Wilemski

Physics Faculty Research & Creative Works

A theoretical formalism for neutron scattering from systems of particles is applied to liquid nanodroplet aerosols. A term arising from intraparticle, intermolecular correlations is identified. The kinematical theory of two body scattering is recast into a form convenient for interpreting the results of experiments with crossed beams of neutrons and aerosol particles. Based on a theoretical analysis of the scattered intensity in the Guinier region, a method for determining the particle velocity directly from the experimental data is outlined. The method is not restricted by assumptions about particle shape, composition, uniformity, or size distribution.

Electron Correlations Observed Through Intensity Interferometry, Michael Schulz, Robert Moshammer, Wayne M. Schmitt, Holger Kollmus, Bernold Feuerstein, Rido Mann, Siegbert Hagmann, Joachim Hermann Ullrich

Physics Faculty Research & Creative Works

Intensity interferometry was applied to study electron correlations in doubly ionizing ion-atom collisions. In this method, the probability to find two electrons emitted in the same double ionization event with a certain momentum difference is compared to the corresponding probability for two uncorrelated electrons from two independent events. The ratio of both probabilities, the so-called correlation function, is found to sensitively reveal electron correlation effects, but it is rather insensitive to the collision dynamics.

An Examination Of A Multidimensional Model Of Customer Satisfaction With Internet Purchasing, Kathleen Vanscoyoc

Theses and Dissertations in Business Administration

The World Wide Web and Internet have transformed the competitive business environment and altered the customer-firm relationship by creating a new retailing format and service enterprise. It is rapidly growing as a competitive distribution medium in which customer satisfaction will be a major success factor in the development and maintenance of this new retailing format. Despite its growing importance as a new shopping medium, little empirical research has been conducted that examines the relationship between Internet shopping, customer satisfaction, company image, and future online purchasing. Research is needed to develop theoretical models that will systematically explain and predict behavior related …

Upper Bounds To The Clique Width Of Graphs, Bruno Courcelle, Stephan Olariu

Computer Science Faculty Publications

Hierarchical decompositions of graphs are interesting for algorithmic purposes. Many NP complete problems have linear complexity on graphs with tree-decompositions of bounded width. We investigate alternate hierarchical decompositions that apply to wider classes of graphs and still enjoy good algorithmic properties. These decompositions are motivated and inspired by the study of vertex-replacement context-free graph grammars. The complexity measure of graphs associated with these decompositions is called clique width. In this paper we bound the clique width of a graph in terms of its tree width on the one hand, and of the clique width of its edge complement on …

Iowa Academy Of Science Membership Directory, 2000-2001, Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Editorial Board, Journal ... 5
Committees ... 6
Sections ... 18
ISTS Regional Directors ... 22
Awards of Merit ... 24
Excellence in Science Teaching Awards ... 25
Past Presidents ... 26
Membership Roster ... 27
Corporate Sponsors ... 63

Virtual Compton Scattering In The Nucleon Resonance Region, Luminita Anca Todor

Physics Theses & Dissertations

This thesis is a study of virtual Compton scattering reaction in which a virtual photon is elastically scattered off a proton γv p → γp. The p( e,e′p)γ reaction was measured in the nucleon resonance region for the first time in the experiment E93-050 in Hall A at Thomas Jefferson National Accelerator Facility. To lowest order in ^αQED, this reaction is a coherent superposition of radiation from the incident or scattered electron in elastic ep scattering (Bethe-Heitler) and exclusive production of a photon on the proton, by absorption of a virtual photon …

Vhdl Design And Simulation For Embedded Zerotree Wavelet Quantisation, Hung Huynh

Theses : Honours

This thesis discusses a highly effective still image compression algorithm – The Embedded Zerotree Wavelets coding technique, as it is called. This technique is simple but achieves a remarkable result. The image is wavelet-transformed, symbolically coded and successive quantised, therefore the compression and transmission/storage saving can be achieved by utilising the structure of zerotree. The algorithm was first proposed by Jerome M. Shapiro in 1993, however to minimise the memory usage and speeding up the EZW processor, a Depth First Search method is used to transverse across the image rather than Breadth First Search method as initially discussed in Shapiro's …

An Investigation On Sun Microsystems Jini Technology, Ferdina D. Soeyadi

Theses : Honours

Sun Microsystems introduced the Jini^TM Technology as its vision of the future in networking, where services can be registered dynamically and he used easily regardless of their location in the network. This is an investigation of feasibility on such claims made by Sun regarding Jini^TM and comparisons with the directly similar Universal Plug and Play from Microsoft. The aim is to implement a simple application of the Jini^TM Technology in order to demonstrate its capabilities as a contribution to the distributed computing research.

Biofilm Composition And Function In Stormwater Constructed Wetland Systems On The Swan Coastal Plain, Western Australia, S. A. Hawkins

Theses : Honours

The ability of natural wetlands to act as effective nutrient sinks and to absorb new nutrient loadings is well documented. Constructed wetland systems (CWSs) aimed at optimising these nutrient removal mechanisms have been used for the removal of nutrients and pollutants from a variety of waters and wastewaters over the past thirty years. Over the past decade, the use of CWSs has extended to the removal of nutrients from urban stormwater, as a more ecologically sensible management option to the traditional method of discharging stormwater into natural wetlands. Stormwater CWSs on the Swan Coastal Plain are designed to remove phosphorus. …

Detecting The Cause Of Acidification At A Seasonal Wetland On The Swan Coastal Plain, Western Australia, Through Laboratory And Field Mesocosm Experiments, Kelli O'Neill

Theses : Honours

Acidification (pH< 4.5) was detected at Lake Jandabup, a shallow, seasonal wetland on the Swan Coastal Plain. Western Australia. Concern has been raised because populations of invertebrate species have declined or disappeared since acidification, potentially compromising the status of the lake as a nature reserve. The Jake bed is underlain with pyrite (feS₂), which oxidises when dry producing sulfates, hydrogen ions and ferrous iron. Being seasonal, Lake Jandabup would be expected to be naturally acidic, but the more recent trend has been a prolonged (> 1 year) and extreme acidification (pH < 4.0). This study endeavoured to explain why the Jake may have undergone an acidic change, why it may have recovered and whether it will happen again. It was hypothesised that the acidification may have been caused by prolonged drying of the lake causing excessive oxidation of pyrite which produced more acid than the wetland could neutralise through buffering. The hypothesis was tested through laboratory and field experiments. The laboratory experiment involved taking intact sediment cores from around the lake, drying them for various lengths of time, and measuring pH, sulfate, total iron, total alkalinity and total aridity upon rehydration. Dried sediment from diatomaceous earth under Fe(OH)₃ precipitate gave the lowest pH of less than 4.0. High sulfates, low alkalinity and low pH were interrelated. While drying in its own right produced low pH, generally there was no significant difference between drying times for release of selected variables. The field experiment involved the establishment of small in situ mesocosms to test for the effects …

The Use Of Stable Isotopic Signatures Of Marine Biota To Map Sewage Effluent Disposed Into The Marine Environment, Adam Gartner

Theses : Honours

Recent work indicates that nitrogen stable isotopic signatures of aquatic biota can be used to link nutrient inputs in the marine environment to terrestrial sources. While this technique of tracing nutrients has been shown to be effective in environments that are not nutrient limited, it has not been proved that this method is effective in oligotrophic environments. This study examined whether nitrogen stable isotopic signatures of marine biota can be used to trace the distribution of sewage effluent in highly mixed, nitrogen limited waters, by examining the δ¹⁵N values of marine biota situated close to and distant from …

Identification Of Wetland Plant Hydrotypes On The Swan Coastal Plain Western Australia, Robyn Loomes

Theses : Honours

The hydrology of 19 Swan Coastal Plain wetlands was described in relation to its influence on the composition and stn1cturc of wetland vegetation. Sixty species were identified as ‘wetland’ plants. The water depth ranges, or hydrological envelopes, of these species were determined and species grouped together based on the water regimes they experienced. Descriptions of wetland hydrology suggested that the surface and groundwater levels of the majority of study wetlands had declined in both the short (3-5 years) and long-term (20-50 years). Wetlands belonging to the Bibra Suite did not follow this trend as surface water levels either increased or …

Virtual Reality And The Modern Ideology Of Order And Control, Craig I. Murrihy

Theses : Honours

In this thesis I will examine the construction of the concept of Virtual Reality. I argue that rather than a technology of liberation as it is often perceived, virtual realities' conception has been influenced significantly by a discourse of control and order. I examine books, articles and films concerning Virtual Reality to support this claim. Furthermore this discourse of control and order is born out of a larger ideology of Western culture that values order and control. Throughout modernity this ideology has manifested itself through techniques and technologies of social and environmental control. I provide a brief historical outline highlighting …

Study Of Fermion Pair Production In E+E- Collisions At 130-183 Gev, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

The cross sections and forward-backward asymmetries of hadronic and leptonic events produced in e+e−e+e− collisions at centre-of-mass energies from 130 to 183 GeV are presented. Results for e+e−e+e−, μ+μ−μ+μ−, τ+τ−τ+τ−, qq¯qq¯, bb¯bb¯ and cc¯cc¯ production show no significant deviation from the Standard Model predictions. This enables constraints to be set upon physics beyond the Standard Model such as four-fermion contact interactions, leptoquarks, Z′Z′ bosons and R-parity violating squarks and sneutrinos. Limits on the energy scale ΛΛ of e+e−ff¯e+e−ff¯ contact interactions are typically in the range from 2 to 10 TeV. Limits on R-parity violating sneutrinos reach masses of a few …

Software Piracy: Attitudes & Opinions Of Computer Users And Implications For Software Manufacturers & Consumers, Bharath Pola

Presidential Scholars Theses (1990 – 2006)

Computer software became registered as a form of literary expression by the United States Copyright Office in 1964. By 1980, the Copyright Act was amended to explicitly include software applications. Today, it is illegal to create copies of original program disks without express permission from the manufacturer (Microsoft 1994). The Software and Information Industry Association (SIIA) states that $2.4 billion worth of copyrighted software was pirated in 1990. This figure represents almost one-half of the total revenue of the software industry for that year. An additional $10 to $12 billion was lost to pirates overseas. However, such statistics maintained by …

An Inquiry Into The Development Of Expert Systems In Legal Reasoning, Trevor K. Sheeley

Presidential Scholars Theses (1990 – 2006)

The first goal of this paper is to review some of the steps necessary in developing a system that reasons effectively in some domain of law. The paper will begin by addressing the issues of domain selection, domain analysis and knowledge acquisition, knowledge representation, and selection of an inference method. After presenting a brief argument against using rule-based reasoning as the primary mode of inference, the paper will go on to expound the virtues of Kevin Ashley's HYPO, a software model of case based legal argument. It will conclude with a short description of my experience implementing part of a …

Structural And Electrical Characterization Of A Novel Mixed Conductor: Ceo2 - Sm2O3 - Zro2 Solid Solution, W. Huang, P. Shuk, M. Greenblatt, M. Croft, Fanglin Chen, M. Liu

Faculty Publications

solid solutions were synthesized for the first time by the hydrothermal method. The electrical properties of the solid solutions have been studied in air and under reducing conditions. Solid solutions with the fluorite structure were formed in all of the studied range of substitution after calcination at 1500°C. With increasing substitution up to 30 mol %, the electronic conductivity increases under a reducing atmosphere. The solid solution has good mixed electronic and ionic conductivity; the total conductivity is 0.42 S/cm at and 700°C with an estimated ionic conductivity of ca. .

The Ups Prototype: An Experimental End-User Service Across E-Print Archives, Herbert Van De Sompel, Thomas Krichel, Michael L. Nelson, Patrick Hochstenbach, Victor Lyapunov, Kurt Maly, Mohammad Zubair, Mohamed Kholief, Xiaoming Liu, Heath O'Connell

Computer Science Faculty Publications

A meeting was held in Santa Fe, New Mexico, October 21-22, 1999, to generate discussion and consensus about interoperability of publicly available scholarly information archives. The invitees represented several well known e-print and report archive initiatives, as well as organizations with interests in digital libraries and the transformation of scholarly communication. The central goal of the meeting was to agree on recommendations that would make the creation of end-user services -- such as scientific search engines and linking systems -- for data originating from distributed and dissimilar archives easier. The Universal Preprint Service (UPS) Prototype was developed in preparation for …

Adaptive Object-Oriented Filtering Framework For Event Management Applications, Ehab Al-Shaer, Mohamed Fayad, Hussein Abdel-Wahab, Kurt Maly

Computer Science Faculty Publications

Event filtering is an essential element in event management applications. In event management environments, the filtering mechanisms are employed to track the events generated from applications at run-time and perform the corresponding appropriate actions. Several key applications domains, such as system and network management, distributed system toolkits, communication protocols and active databases, utilize event filtering for various management purposes. The goal of this paper is to describe the object-oriented design and implementation of an adaptive event filtering framework which can be integrated and reused efficiently to develop event management applications for various domain environments. In our approach, the event filtering …

Carbonate Deposition And Sequence Stratigraphy Of The Terminal Cambrian Grand Cycle In The Southern Appalachians, U.S.A, Bosiljka Glumac, Kenneth R. Walker

Geosciences: Faculty Publications

The cessation of shale and carbonate deposition of the Conasauga Group grand cycles (Middle to Upper Cambrian) and the establishment of the widespread peritidal carbonate deposition of the Knox Group (Upper Cambrian to Lower Ordovician) represent a prominent change in sedimentation along the early Paleozoic passive continental margin in the southern Appalachians. To evaluate the causes for this change, this study focuses on the Maynardville Formation, which is the uppermost carbonate unit of the Conasauga Group. The Maynardville consists of: (1) a lower subtidal faciès succession, which is underlain by the Nolichucky Shale and resembles the rest of the Conasauga …

A Wide Field 90 Cm Vla Image Of The Galactic Center Region, Ted La Rosa, Namir E. Kassim, Joseph W. Lazlo, Scott B. Hyman

Faculty Articles

We present a wide-field, high dynamic range, high-resolution, long-wavelength (lambda = 90 cm) VLA image of the Galactic center region. The image is centered on Sgr A, covers an area of 4 degrees x 5 degrees with an angular resolution of 43 ", and has a rms sensitivity of approximate to 5 mJy beam-l. The image was constructed from archival (1989 and 1991) VLA data of Pedlar et al. and Anantharamaiah et al. using new three-dimensional image restoration techniques. These three-dimensional imaging techniques resolve the problem of non-coplanar baselines encountered at long wavelengths and yield distortion-free imaging of far-field sources …

Isozyme Polymorphism In The Vigna Frutescens-V. Membranacea Complex (Tribe Phaseoleae, Fabaceae), Rémy S. Pasquet, Thierry Vanderborght

All Peer-Reviewed Publications

An electrophoretic comparison of variation at 29 isozyme loci was performed for 21 Vigna accessions belonging to V. frutescens, V. membranacea and V. friesiorum. The results do not fit accepted nomenclature and the taxonomic ranks should be reassessed. V. frutescens, V. friesiorum, and various subspecies of V. membranacea should be considered as putative species, although hybridisation data are needed in order to obtain a clear picture of the organisation of this gene pool. However, the results do not support the existence of two sections, and section Liebrechtsia is merged with section Macrodontae in a newly enlarged section Macrodontae.

Arguing About Consensus: Examining The Case Against Western Watershed Initiatives And Other Collaborative Groups Active In Natural Resources Management, Douglas S. Kenney, University Of Colorado Boulder. Natural Resources Law Center

Books, Reports, and Studies

x, 72 leaves

Laws Influencing Community-Based Conservation In Colorado And The American West: A Primer, University Of Colorado Boulder. Natural Resources Law Center

Books, Reports, and Studies

vi, 51 p.

The New Watershed Source Book: A Directory And Review Of Watershed Initiatives In The Western United States, Douglas S. Kenney, Sean T. Mcallister, William H. Caile, Jason S. Peckham, University Of Colorado Boulder. Natural Resources Law Center

Books, Reports, and Studies

xiii, 460 p. : ill., maps ; 28 cm

Quantitative Analysis Of Ultra-Fine Goethite In Rust Layer On Steel Using Mossbauer And X-Ray Diffraction Spectroscopy, Masato Yamashita, Toshihei Misawa, H. E. Townsend, D. C. Cook

Physics Faculty Publications

We have proposed determination procedure of the relative amounts of rust constituents of steel. Mossbauer spectroscopy provides the relative amounts of crystalline rust constituents including ultra-fine crystals. A quantitative analysis of ultra-fine crystals is possible with the resolution of several percent by comparing the Mossbauer results with the relative amounts of rust constituents determined by X-ray diffraction spectroscopy.

Interaction Of Laser Radiation With A Negative Ion In The Presence Of A Strong Static Electric Field, N. L. Manakov, M. V. Frolov, Anthony F. Starace, Ilya I. Fabrikant

Anthony F. Starace Publications

This paper provides a general theoretical description of a weakly bound atomic system (a negative ion) interacting simultaneously with two (generally strong) fields, a static electric field and a monochromatic laser field having an arbitrary elliptical polarization. The zero-range δ-potential is used to model the interaction of a bound electron in a negative ion as well as the interaction of a detached electron with the residual atom. Our treatment combines the quasistationary (complex energy) and quasienergy (Floquet) approaches. This quasistationary, quasienergy state (QQES) formalism is the most appropriate one for analysing a decaying quantum system under the influence of a …

Electronic Scattering From Co/Cu Interfaces: In-Situ Measurement And Comparison With Theory, W. E. Bailey, Shan X. Wang, Evgeny Y. Tsymbal

Evgeny Tsymbal Publications

The full thickness-dependent electrical conductivity of polycrystalline NiO/Co/Cu/Co spin-valve structures was measured in situ during ion-beam deposition and compared with calculations based on realistic band structure. We have found striking features in the experimental conductivity which are unexpected from widely used semiclassical free-electron models. Addition of ∼ 1 ML Co to a NiO/Co/Cu surface causes the net film conductance to decrease; the reverse case of Cu on NiO/Co shows a strong positive curvature of the thicknessdependent conductance, indicating a reduction of the conductivity in Cu near the interface with Co. Quantitative agreement is found between the experimental thickness-dependent film conductance …

Restoring Ecological Integrity Of Great Rivers: Historical Hydrographs Aid In Defining Reference Conditions For The Missouri River, David L. Galat, Robin Lipkin

United States Geological Survey: Staff Publications

Restoring the ecological integrity of regulated large rivers necessitates characterizing the natural flow regime. We applied ‘Indicators of Hydrologic Alteration’ to assess the natural range of variation of the Missouri River’s flow regime at 11 locations before (1929–1948) and after (1967–1996) mainstem impoundment. The 3768 km long Missouri River was divided into three sections: upper basin least-altered from flow regulation, including the lower Yellowstone River; middle basin inter-reservoir, and lower basin channelized. Flow regulation was associated with a reduction in magnitude and duration of the annual flood pulse, an increase in magnitude and duration of annual discharge minima, a reduction …

Heavily Fluorinated Sugar Analogs, Stephen G. Dimagno

Department of Chemistry: Faculty Publications

Heavily fluorinated Sugar analogs of formula

wherein R₁ is selected from alkyl, alkenyl, aryl, CH₂OH, -CH₂-O-alkyl, -CH₂-O-aryl, -CH₂OPO₃H, -CH₂-O-carbohydrate, -CH₂-NH-peptide, or -CH₂-O-peptide; wherein R₂ is selected from hydroxy, -O-carbohydrate, -NH-peptide,

wherein R₃ is selected from H, halogen, lower alkyl, lower alkenyl, lower haloalkyl, lower haloalkenyl, amino, mono- or di-lower alkylamino; wherein R₄ is Selected from amino, hydroxy, alkoxy, or halogen; and wherein R₅ is H or amino. The compounds of formula (I) are useful as antiviral and antineoplastic agents …