Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

2006

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 1441 - 1470 of 5872

Full-Text Articles in Physical Sciences and Mathematics

Teaching Time Savers: Style Points, Michael E. Orrison Jr. Aug 2006

Teaching Time Savers: Style Points, Michael E. Orrison Jr.

All HMC Faculty Publications and Research

When I began as an assistant professor, I had a pretty good sense of how much time it would take for me to prepare for each class. After a few conversations with my new colleagues, I even had a good sense of how much time I should devote to tasks like office hours and committee work. Somewhere in the middle of grading my first exam, though, it became painfully clear that I had underestimated the amount of time I would need to grade exams!


Cobaltocene Adsorption And Dissociation On Cu(1 1 1), Jaewu Choi, Peter A. Dowben Aug 2006

Cobaltocene Adsorption And Dissociation On Cu(1 1 1), Jaewu Choi, Peter A. Dowben

Peter Dowben Publications

Photoemission results indicate that the initial adsorption of cobaltocene on Cu(1 1 1) at 150 K leads to molecular fragmentation, but with subsequent cobaltocene exposures, molecular absorption occurs. The molecularly adsorbed species is either adsorbed with only a fraction of molecules adopting a preferential orientation along the surface normal or adsorbed with the molecular axis away from the surface normal. This adsorption behavior is compared to nickelocene and ferrocene adsorption.


Min–Max Hyperellipsoidal Clustering For Anomaly Detection In Network Security, Suseela T. Sarasamma, Qiuming Zhu Aug 2006

Min–Max Hyperellipsoidal Clustering For Anomaly Detection In Network Security, Suseela T. Sarasamma, Qiuming Zhu

Computer Science Faculty Publications

A novel hyperellipsoidal clustering technique is presented for an intrusion-detection system in network security. Hyperellipsoidal clusters toward maximum intracluster similarity and minimum intercluster similarity are generated from training data sets. The novelty of the technique lies in the fact that the parameters needed to construct higher order data models in general multivariate Gaussian functions are incrementally derived from the data sets using accretive processes. The technique is implemented in a feedforward neural network that uses a Gaussian radial basis function as the model generator. An evaluation based on the inclusiveness and exclusiveness of samples with respect to specific criteria is …


Ab-Initio Calculations Of The Charge-Density Response In Complex Materials, Oscar Dario Restrepo Tovar Aug 2006

Ab-Initio Calculations Of The Charge-Density Response In Complex Materials, Oscar Dario Restrepo Tovar

Doctoral Dissertations

Our main goal is to have a realistic description of the charge excitations in complex materials in the range of energies such as the coulomb energy U, which is in the eV range. Spectra of these charge excitations, for a large range of wave vector transfers, may provide signatures of the underlying electronic structures. The charge-density response function calculated within Time-dependent Density functional (TDDFT) is an ideal theoretical framework for the calculation of these excitations, since comparison with experimental data (in particular with non-resonant inelastic x-ray scattering experiments) can be done in absolute units (without the need of any adjustable …


Neutron Scat- Tering In The Novel Quantum Magnets: Livo2 And Dmacucl3, Wei Tian Aug 2006

Neutron Scat- Tering In The Novel Quantum Magnets: Livo2 And Dmacucl3, Wei Tian

Doctoral Dissertations

The behavior of magnetic systems in the extreme quantum limit is one of the most interesting forefront areas in condensed matter physics. This dissertation investigates two particularly interesting quantum magnets: LiVO2 and DMACuCl3. Systematic studies were performed on single crystal samples using different experimental techniques, especially inelastic neutron scattering. Detailed experimental results and corresponding model calculations are presented and discussed in this dissertation.

LiVO2 is a good candidate to study the interplay between “magnetic frustration” and orbital ordering. V3+ ions in LiVO2 form a triangular lattice involving threefold degenerate t2g orbitals. LiVO2 undergoes …


Microwave Reflectometry As A Novel Diagnostic Tool For Detection Of Skin Cancers, Pratik Mehta, Kundan Chand, Deepak Narayanswamy, Daryl G. Beetner, R. Zoughi, William V. Stoecker Aug 2006

Microwave Reflectometry As A Novel Diagnostic Tool For Detection Of Skin Cancers, Pratik Mehta, Kundan Chand, Deepak Narayanswamy, Daryl G. Beetner, R. Zoughi, William V. Stoecker

Electrical and Computer Engineering Faculty Research & Creative Works

More than 1 000 000 people are diagnosed with skin cancer each year in the United States, and more than 10 000 people die from the disease. Methods such as visual inspection and dermoscopy are available for early detection of skin cancers, but improvement in accuracy is needed. This paper investigates the use of microwave reflectometry as a potential diagnostic tool for detection of skin cancers. Open-ended coaxial probes were used to measure microwave properties of skin. The influences of measurement parameters such as probe application pressure, power level, and variation in reflection properties of skin with location and hydration …


Variations On U-Shaped Learning, Lorenzo Carlucci, Sanjay Jain, Efim Kinber, Frank Stephen Aug 2006

Variations On U-Shaped Learning, Lorenzo Carlucci, Sanjay Jain, Efim Kinber, Frank Stephen

School of Computer Science & Engineering Faculty Publications

The paper deals with the following problem: is returning to wrong conjectures necessary to achieve full power of algorithmic learning? Returning to wrong conjectures complements the paradigm of U-shaped learning when a learner returns to old correct conjectures. We explore our problem for classical models of learning in the limit from positive data: explanatory learning (when a learner stabilizes in the limit on a correct grammar) and behaviourally correct learning (when a learner stabilizes in the limit on a sequence of correct grammars representing the target concept). In both cases we show that returning to wrong conjectures is necessary to …


Exponents For B-Stable Ideals, Eric Sommers, Julianna Tymoczko Aug 2006

Exponents For B-Stable Ideals, Eric Sommers, Julianna Tymoczko

Mathematics Sciences: Faculty Publications

Let G be a simple algebraic group over the complex numbers containing a Borel subgroup B. Given a B-stable ideal I in the nilradical of the Lie algebra of B, we define natural numbers m 1, m 2,. . .,m k which we call ideal exponents. We then propose two conjectures where these exponents arise, proving these conjectures in types A n, B n, C n and some other types. When I = 0, we recover the usual exponents of G by Kostant (1959), and one of our conjectures reduces to a well-known factorization of the Poincaré polynomial of the …


Susceptibility Of Greater Sage-Grouse To Experimental Infection With West Nile Virus, Larry Clark, Jeffrey Hall, Robert Mclean, Michael Dunbar, Kaci Klenk, Richard Bowen, Cynthia A. Smeraski Aug 2006

Susceptibility Of Greater Sage-Grouse To Experimental Infection With West Nile Virus, Larry Clark, Jeffrey Hall, Robert Mclean, Michael Dunbar, Kaci Klenk, Richard Bowen, Cynthia A. Smeraski

United States Department of Agriculture Wildlife Services: Staff Publications

Populations of greater sage-grouse (Centrocercus urophasianus) have declined 45– 80% in North America since 1950. Although much of this decline has been attributed to habitat loss, recent field studies have indicated that West Nile virus (WNV) has had a significant negative impact on local populations of grouse. We confirm the susceptibility of greater sage-grouse to WNV infection in laboratory experimental studies. Grouse were challenged by subcutaneous injection of WNV (103.2 plaque-forming units [PFUs]). All grouse died within 6 days of infection. The Kaplan-Meier estimate for 50% survival was 4.5 days. Mean peak viremia for nonvaccinated birds was 106.4 PFUs/ml (6100.2 …


Wmi Outdoor News Bulletin * August 2006, Volume 60, No. 8 Aug 2006

Wmi Outdoor News Bulletin * August 2006, Volume 60, No. 8

Wildlife Management Institute Outdoor News Bulletin

New report reveals problems with Bison Range agreement

WMI's Distinguished Service Award gets distinguished namesake

Wyoming and feds still growling over wolf management

New twist in reauthorization of Great Lakes Fish and Wildlife Restoration Act

Worth reading: Marley & Me


Magnetic Moment Softening And Domain Wall Resistance In Ni Nanowires, John D. Burton, Renat F. Sabirianov, Sitaram S. Jaswal, Evgeny Y. Tsymbal, O. N. Mryasov Aug 2006

Magnetic Moment Softening And Domain Wall Resistance In Ni Nanowires, John D. Burton, Renat F. Sabirianov, Sitaram S. Jaswal, Evgeny Y. Tsymbal, O. N. Mryasov

Evgeny Tsymbal Publications

We perform ab initio calculations of the electronic structure and conductance of atomic-size Ni nanowires with domain walls only a few atomic lattice constants wide. We show that the hybridization between noncollinear spin states leads to a reduction of the magnetic moments in the domain wall resulting in the enhancement of the domain wall resistance. Experimental studies of the magnetic moment softening may be feasible with modern techniques such as scanning tunneling spectroscopy.


Strychninium (S)-2-(2-Bromo­Phen­Oxy)Propanoate 1.4-Hydrate, Kraig A. Wheeler, Aaron M. Lineberry Aug 2006

Strychninium (S)-2-(2-Bromo­Phen­Oxy)Propanoate 1.4-Hydrate, Kraig A. Wheeler, Aaron M. Lineberry

Faculty Research and Creative Activity

In the title mol­ecular salt, C21H23N2O2+·C9H8BrO3−·1.4H2O, the components are linked by inter­molecular C—O−⋯H—+N and OW—H⋯O inter­actions.


Magnetic Moment Softening And Domain Wall Resistance In Ni Nanowires, J. D. Burton, Renat F. Sabirianov, Sitaram Jaswal, Evgeny Y. Tsymbal, Oleg N. Mryasov Aug 2006

Magnetic Moment Softening And Domain Wall Resistance In Ni Nanowires, J. D. Burton, Renat F. Sabirianov, Sitaram Jaswal, Evgeny Y. Tsymbal, Oleg N. Mryasov

Physics Faculty Publications

We perform ab initio calculations of the electronic structure and conductance of atomic-size Ni nanowires with domain walls only a few atomic lattice constants wide. We show that the hybridization between noncollinear spin states leads to a reduction of the magnetic moments in the domain wall resulting in the enhancement of the domain wall resistance. Experimental studies of the magnetic moment softening may be feasible with modern techniques such as scanning tunneling spectroscopy.


Trigger For Group A Streptococcal M1t1 Invasive Disease, J. N. Cole, Jason D. Mcarthur, F. C. Mckay, Martina L. Sanderson-Smith, Amanda J. Cork, Marie Ranson, M. Rohde, A. Itzek, H. Sun, D. Ginsburg, M. Kotb, V. Nizet, G. S. Chhatwal, Mark J. Walker Aug 2006

Trigger For Group A Streptococcal M1t1 Invasive Disease, J. N. Cole, Jason D. Mcarthur, F. C. Mckay, Martina L. Sanderson-Smith, Amanda J. Cork, Marie Ranson, M. Rohde, A. Itzek, H. Sun, D. Ginsburg, M. Kotb, V. Nizet, G. S. Chhatwal, Mark J. Walker

Faculty of Science - Papers (Archive)

The globally disseminated Streptococcus pyogenes M1T1 clone causes a number of highly invasive human diseases. The transition from local to systemic infection occurs by an unknown mechanism; however invasive M1T1 clinical isolates are known to express significantly less cysteine protease SpeB than M1T1 isolates from local infections. Here, we show that in comparison to the M1T1 strain 5448, the isogenic mutant ∆speB accumulated 75-fold more human plasmin activity on the bacterial surface following incubation in human plasma. Human plasminogen was an absolute requirement for M1T1 strain 5448 virulence following subcutaneous infection of humanized plasminogen transgenic mice. S. pyogenes M1T1 isolates …


Generalization And Enforcement Of Role-Based Access Control Using A Novel Event-Based Approach, Raman Adaikkalavan Aug 2006

Generalization And Enforcement Of Role-Based Access Control Using A Novel Event-Based Approach, Raman Adaikkalavan

Computer Science and Engineering Dissertations

Protecting information against unauthorized access is a key issue in information system security. Advanced access control models and mechanisms have now become necessary for applications and systems due to emerging acts, such as the Health Insurance Portability and Accountability Act (HIPAA) and the Sarbanes-Oxley Act. Role-Based Access Control (RBAC) is a viable alternative to traditional discretionary and mandatory access control. RBAC has been shown to be cost effective and is being employed in various application domains on account of its characteristics: rich specification, policy neutrality, separation of duty relations, principle of least privilege, and ease of management. Existing RBAC approaches …


Geoexpert - An Expert System Based Framework For Data Quality In Spatial Databases, Aditya Kumar Aug 2006

Geoexpert - An Expert System Based Framework For Data Quality In Spatial Databases, Aditya Kumar

Masters Theses & Specialist Projects

Usage of very large sets of historical spatial data in knowledge discovery process became a common trend, and in order to obtain better results from this knowledge discovery process the data should be of high quality. In this thesis we proposed a framework 'GeoExpert' for data quality assessment and cleansing tool for spatial data that integrates the spatial data visualization and analysis capabilities of the ARCGIS, the reason and inference capability of an expert system. In this thesis we implemented the proposed framework both stand-alone and web versions using ArcGIS Engine and ArcGIS Server, respectively. We used JESS expert system …


Chainability And Hemmingsen's Theorem, Paul Bankston Aug 2006

Chainability And Hemmingsen's Theorem, Paul Bankston

Mathematics, Statistics and Computer Science Faculty Research and Publications

On the surface, the definitions of chainability and Lebesgue covering dimension ⩽1 are quite similar as covering properties. Using the ultracoproduct construction for compact Hausdorff spaces, we explore the assertion that the similarity is only skin deep. In the case of dimension, there is a theorem of E. Hemmingsen that gives us a first-order lattice-theoretic characterization. We show that no such characterization is possible for chainability, by proving that if κ is any infinite cardinal and AA is a lattice base for a nondegenerate continuum, then AA is elementarily equivalent to a lattice base for a continuum Y …


The Radio Structure Of Radio-Quiet Quasars, C. Leipski, H. Falcke, N. Bennert, S. Hüttenmeister Aug 2006

The Radio Structure Of Radio-Quiet Quasars, C. Leipski, H. Falcke, N. Bennert, S. Hüttenmeister

Physics

Aims. We investigate the radio emitting structures of radio-quiet active galactic nuclei with an emphasis on radio-quiet quasars to study their connection to Seyfert galaxies. Methods. We present and analyse high-sensitivity VLA radio continuum images of 14 radio-quiet quasars and six Seyfert galaxies. Results. Many of the low redshift radio-quiet quasars show radio structures that can be interpreted as jet-like outflows. However, the detection rate of extended radio structures on arcsecond scales among our sample decreases with increasing redshift and luminosity, most likely due to a lack of resolution. The morphologies of the detected radio emission indicate strong interactions of …


Upper Flow Regime Sheets, Lenses And Scour Fills: Extending The Range Of Architectural Elements For Fluvial Sediment Bodies, Christopher R. Fielding Aug 2006

Upper Flow Regime Sheets, Lenses And Scour Fills: Extending The Range Of Architectural Elements For Fluvial Sediment Bodies, Christopher R. Fielding

Department of Earth and Atmospheric Sciences: Faculty Publications

Fluvial strata dominated internally by sedimentary structures of interpreted upper flow regime origin are moderately common in the rock record, yet their abundance is not appreciated and many examples may go unnoticed. A spectrum of sedimentary structures is recognised, all of which occur over a wide range of scale: 1. cross-bedding with humpback, sigmoidal and ultimately low-angle cross-sectional foreset geometries (interpreted as recording the transition from dune to upper plane bed bedform stability field), 2. planar/flat lamination with parting lineation, characteristic of the upper plane bed phase, 3. flat and low-angle lamination with minor convex-upward elements, characteristic of the transition …


Does Joseph's Letter To Emma Of 4 November 1838 Show That He Knew About Chiasmus?, Boyd F. Edwards, W. F. Edwards Aug 2006

Does Joseph's Letter To Emma Of 4 November 1838 Show That He Knew About Chiasmus?, Boyd F. Edwards, W. F. Edwards

All Physics Faculty Publications

No abstract provided.


Investigation Of Negative Refractive Index In Reciprocal Chiral Materials, Monish Ranjan Chatterjee, Partha P. Banerjee, Pradeep R. Anugula Aug 2006

Investigation Of Negative Refractive Index In Reciprocal Chiral Materials, Monish Ranjan Chatterjee, Partha P. Banerjee, Pradeep R. Anugula

Electrical and Computer Engineering Faculty Publications

It is well known that there exist both natural materials (such as milk or sugar solution) possessing chiral (or handed) properties, as well as an increasing list of man-made materials (such as sodium bromate) that exhibit chirality. One of the principal properties of chirality is that light of any arbitrary polarization, when propagating through a chiral material, splits up into two circular polarizations propagating in different directions. In the past decade or longer, researchers have investigated electromagnetic transverse (plane) wave propagation across a non-chiral/chiral interface, and determined the electromagnetic Fresnel coefficients for such propagation. Traditionally, such coefficients are derived under …


Baylisascaris Procyonis (Nematoda: Ascaridoidea) In Raccoons (Procyon Lotor) From Duval County, Texas, David B. Long, Tyler A. Campbell, Scott E. Henke Aug 2006

Baylisascaris Procyonis (Nematoda: Ascaridoidea) In Raccoons (Procyon Lotor) From Duval County, Texas, David B. Long, Tyler A. Campbell, Scott E. Henke

United States Department of Agriculture Wildlife Services: Staff Publications

Baylisascaris procyonis, or the raccoon roundworm, primarily utilizes the raccoon as its definitive host, and has been found in >90 species of North American animal intermediate hosts (mostly birds, lagomorphs, and rodents) (Kazacos 2001). In non-raccoon hosts, including humans, larvae of this parasitic nematode can cause severe neurological disease (cerebrospinal nematodiasis) and often damage visceral and ocular tissues (Kazacos 2001). Formerly, B. procyonis was not thought to occur in Texas (Chandler 1942; Schaffer et al. 1981). However, it was recently discovered in raccoons occurring in moist environments of coastal areas (Kerr et al. 1997) and in eastern portions of …


A Simulation Model For Determining Cost-Effectiveness Of Fences For Reducing Deer Damage, Kurt C. Vercauteren, Michael J. Lavelle, Scott E. Hygnstrom Aug 2006

A Simulation Model For Determining Cost-Effectiveness Of Fences For Reducing Deer Damage, Kurt C. Vercauteren, Michael J. Lavelle, Scott E. Hygnstrom

United States Department of Agriculture Wildlife Services: Staff Publications

The installation of fences to protect agricultural products, natural resources, or other areas from deer (Odocoileus spp.) can be expensive and potential benefits of fencing are difficult to quantify. A rational method is needed to help evaluate whether fencing can be cost-effective and which fence designs will be optimal for particular applications. We describe an interactive, dynamic simulation model that conducts economic analyses and predicts economic benefit associated with fences for crops relative to area and perimeter of protected plot, value of crop, percentage of crop damaged by deer annually prior to fencing, efficacy of fence, and costs of fence …


The John Muir Newsletter, Fall 2006, The John Muir Center For Environmental Studies Aug 2006

The John Muir Newsletter, Fall 2006, The John Muir Center For Environmental Studies

Muir Center Newsletters (1981-2015)

The John Muir pr/- FEB UNlVfeHSnY 0F THE PACIFIC, STOCKTON, CA VOLUME 16, NC1MBKX 4 Fall 2006 John Muir's World Tour (part IV) Introduction by W. R. Swagerty Director, John Muir Center Edited by John Hurley and W.R. Swagerty In Part IV of John Muir's unpublished World Tour, we follow Muir from Egypt to Ceylon (Sri Lanke) to Australia. Notebook "# 51" begins with a description of Suez as a "queer old town" followed by praise for the oasis-environment that produces so many palms and bananas. Much of the notebook focuses on Muir's touring of the Pyramids, those "stupendous monuments …


4,4′-(1,1,1,3,3,3-Hexafluoro­Propane-2,2-Diyl)Bis­(Benzoyl Chloride), Cecilia Rodriguez De Barbarin, Sylvain Bernes, Javier Macossay-Torres, Patrick E. Cassidy Aug 2006

4,4′-(1,1,1,3,3,3-Hexafluoro­Propane-2,2-Diyl)Bis­(Benzoyl Chloride), Cecilia Rodriguez De Barbarin, Sylvain Bernes, Javier Macossay-Torres, Patrick E. Cassidy

Chemistry Faculty Publications and Presentations

In the structure of the title mol­ecule, C17H8Cl2F6O2, the dihedral angle between the least-squares planes of the benzene rings is 66.31 (15)°. The CF3 groups adopt an eclipsed conformation.


Implications Of Mass Education On Chemistry Higher Education, Christine O'Connor Aug 2006

Implications Of Mass Education On Chemistry Higher Education, Christine O'Connor

Articles

The following paper discusses the implications of government policy for widening access and participation in third level institutes. The increase in ‘non-traditional’ students has been widely recognised on an international scale; however, some issues of inequality still exist. The ‘struggles’ associated with widening participation and the creation of a ‘new’ student type are discussed, with particular reference to chemistry education. A change is needed with regard to the pedagogical approach taken by staff in order to cater for a diverse student body comprising a broad range of learner types, and this must be supported both at departmental and institutional levels. …


Coarse Structures And Higson Compactification, Christian Stuart Hoffland Aug 2006

Coarse Structures And Higson Compactification, Christian Stuart Hoffland

Masters Theses

FOLLOWING John Roe in his Lectures on Coarse Geometry, we begin by describing the large-scale structure of metric spaces by means of coarse maps between them, those being maps which preserve distances at large scales. Using these techniques, we demonstrate that the real numbers and the integers have the same large scale structure--or are coarsely equivalent--but that the real line is coarsely equivalent to neither the Euclidean plane nor the set of positive real numbers. Following a generalization of these concepts for general topological spaces with the introduction of an abstract coarse structure on the space, we show, among …


Pseudostationary Phase For Solid Phase Extraction, Qing Zhao Aug 2006

Pseudostationary Phase For Solid Phase Extraction, Qing Zhao

Masters Theses & Specialist Projects

A unique pseudostationary phase for Solid Phase Extraction is presented. This pseudostationary phase consists of surfactant, which is initially immobilized onto hydrophilic cation exchange resin. The surfactant chain through hydrophobic interactions extracts hydrophobic analytes in the same manner as conventional bonded alkyl moieties on silica based non-polar sorbents. Although hydrophobic analytes can be efficiently trapped on commercially available non-polar sorbents (i.e. Ci8 silica), organic solvents that are necessary to break strong hydrophobic interactions between the analytes and the sorbent are harmful. They are also incompatible for direct introduction into a reversed phase liquid chromatographic set up. In the presented approach, …


Water Solubility Characteristics Of Hydrophobically Modified Polyethyleneimines, Jennifer N. Williams Aug 2006

Water Solubility Characteristics Of Hydrophobically Modified Polyethyleneimines, Jennifer N. Williams

Browse all Theses and Dissertations

Commercially available polyethyleneimines varying in molecular weights and viscosities were synthetically modified in order to increase their hydrophobicity when dissolved in water. Used as additives for inkjet industry inks, these polymers have been designed to promote interaction between formulated inks and paper, while increasing the water-fastness of these water-soluble inks once they are dried on bond paper. Waterfastness, the ability of an ink to maintain print integrity once it becomes wet, as well as optical density, solubility, pH, molecular weight, polydispersity and viscosity are amongst the characteristics analyzed. The modifications of these polyethyleneimines (PEis) with alkyl bromides and alkyl epoxides …


Learning State And Action Space Hierarchies For Reinforcement Learning Using Action-Dependent Partitioning, Mehran Asadi Aug 2006

Learning State And Action Space Hierarchies For Reinforcement Learning Using Action-Dependent Partitioning, Mehran Asadi

Computer Science and Engineering Dissertations

Autonomous systems are often dicult to program. Reinforcement learning (RL) is an attractive alternative, as it allows the agent to learn behavior on the basis of sparse, delayed reward signals provided only when the agent reaches desired goals. Recent attempts to address the dimensionality of RL have turned to principled ways of exploiting temporal abstraction, where decisions are not required at each step, but rather invoke the execution of temporally-extended activities which follow their own policies un- til termination. This leads naturally to hierarchical control architectures and associated learning algorithms. This dissertation reviews several approaches to temporal abstraction and hierarchical …