Physical Sciences and Mathematics Commons^™

Harmonic Functions On R-Covered Foliations And Group Actions On The Circle, Sergio Fenley, Renato Feres, Kamlesh Parwani

Faculty Research and Creative Activity

Let (M,F) be a compact codimension-one foliated manifold whose leaves are equipped with Riemannian metrics, and consider continuous functions on M that are harmonic along the leaves of F. If every such function is constant on leaves we say that (M,F) has the Liouville property. Our main result is that codimension-one foliated bundles over compact negatively curved manifolds satisfy the Liouville property. Related results for R-covered foliations, as well as for discrete group actions and discrete harmonic functions, are also established.

Harmonic Functions On R-Covered Foliations And Group Actions On The Circle, Sergio Fenley, Renato Feres, Kamlesh Parwani

Faculty Research and Creative Activity

Let (M,F) be a compact codimension-one foliated manifold whose leaves are equipped with Riemannian metrics, and consider continuous functions on M that are harmonic along the leaves of F. If every such function is constant on leaves we say that (M,F) has the Liouville property. Our main result is that codimension-one foliated bundles over compact negatively curved manifolds satisfy the Liouville property. Related results for R-covered foliations, as well as for discrete group actions and discrete harmonic functions, are also established.

Rfid-Based Smart Freezer, Ahmet Soylemezoglu, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel radio-frequency identification (RFID)-based smart freezer using a new inventory-management scheme for extremely low temperature environments. The proposed solution utilizes backpressure inventory control, systematic selection of antenna configuration, and antenna power control. The proposed distributed-inventory-control (DIC) scheme dictates the amount of items transferred through the supply chain. when a high item visibility is ensured, the control scheme maintains the desired level of inventory at each supply-chain echelon. The performance of the DIC scheme is guaranteed using a Lyapunov-based analysis. The proposed RFID antenna-configuration design methodology coupled with locally asymptotically stable distributed power control ensures a 99% …

Joint Routing And Link Rate Allocation Under Bandwidth And Energy Constraints In Sensor Networks, Maggie Cheng, Xuan Gong, Lin Cai

Computer Science Faculty Research & Creative Works

In sensor networks, both energy and bandwidth are scarce resources. in the past, many energies efficient routing algorithms have been devised in order to maximize network lifetime, in which wireless link bandwidth has been optimistically assumed to be sufficient. This article shows that ignoring the bandwidth constraint can lead to infeasible routing solutions. as energy constraint affects how data should be routed, link bandwidth also affects not only the routing topology but also the allowed data rate on each link. in this paper, we discuss the sufficient condition on link bandwidth that makes a routing solution feasible, then provide mathematical …

Optimal Control Of Unknown Affine Nonlinear Discrete-Time Systems Using Offline-Trained Neural Networks With Proof Of Convergence, Travis Dierks, Balaje T. Thumati, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

The optimal control of linear systems accompanied by quadratic cost functions can be achieved by solving the well-known Riccati equation. However, the optimal control of nonlinear discrete-time systems is a much more challenging task that often requires solving the nonlinear Hamilton-Jacobi-Bellman (HJB) equation. in the recent literature, discrete-time approximate dynamic programming (ADP) techniques have been widely used to determine the optimal or near optimal control policies for affine nonlinear discrete-time systems. However, an inherent assumption of ADP requires the value of the controlled system one step ahead and at least partial knowledge of the system dynamics to be known. in …

Cs 240: Introduction To Computer Science I, Vanessa Starkey

Computer Science & Engineering Syllabi

Basic concepts of programming and programming languages are introduced.
Emphasis is on structured programming and stepwise refinement. Prerequisite: MTH 130 or MPL 5.

Polarization Switching Kinetics Of Ferroelectric Nanomesas Of Vinylidene Fluoride-Trifluoroethylene Copolymer, R. V. Gaynutdinov, O. A. Lysova, S. G. Yudin, A. L. Tolstikhina, A. L. Kholkin, V. M. Fridkin, Stephen Ducharme

Stephen Ducharme Publications

The polarization switching kinetics of ferroelectric polymer nanomesas was investigated using piezoresponse force microscopy. The nanomesas were made by self-organization from Langmuir–Blodgett films of a 70% vinylidene fluoride and 30% trifluoroethylene copolymer. The polarization switching time exhibits an exponential dependence on reciprocal voltage that is consistent with nucleation-type switching dynamics.

Unified Behavior Framework For Reactive Robot Control, Brian G. Woolley, Gilbert L. Peterson

Faculty Publications

Behavior-based systems form the basis of autonomous control for many robots. In this article, we demonstrate that a single software framework can be used to represent many existing behavior based approaches. The unified behavior framework presented, incorporates the critical ideas and concepts of the existing reactive controllers. Additionally, the modular design of the behavior framework: (1) simplifies development and testing; (2) promotes the reuse of code; (3) supports designs that scale easily into large hierarchies while restricting code complexity; and (4) allows the behavior based system developer the freedom to use the behavior system they feel will function the best. …

A Thermodynamic And Kinetic Characterization Of The Solvent Dependence Of The Saddle-Crown Equilibrium Of Cyclotriveratrylene (Ctv) Oxime, David C. French, Marlon R. Lutz Jr., Chichi Lu, Matthias Zeller, Daniel Becker

Chemistry: Faculty Publications and Other Works

The equilibration of the saddle conformer of cyclotriveratrylene (CTV) oxime to the corresponding crown conformer was followed by (1)H NMR in five separate solvents, and kinetic and thermodynamic parameters were determined from the NMR data. The oxime saddle conformers of 3 are favored in CDCl(3) (K(eq) = [saddle]/[crown] = 1.4), whereas the CTV oxime crown conformer 3a is favored in three more polar solvents studied (DMSO-d(6), acetonitrile-d(3), acetone-d(6)). Surprisingly, the CTV oxime crown conformer is also slightly favored in the nonpolar solvent 1,4-dioxane-d(8). These behaviors are discussed in terms of hydrogen bonding, entropy, and possible host-guest considerations. An X-ray crystal …

Creation Of Multiple Electron-Positron Pairs In Arbitrary Fields, T Cheng, Q Su, Rainer Grobe

Faculty publications – Physics

We examine the spontaneous breakdown of the matter vacuum triggered by an external force of arbitrary strength and spatial and temporal variations. We derive a nonperturbative framework that permits the computation of the complete time evolution of various multiple electron-positron pair probabilities. These time-dependent probabilities can be computed from a generating function as well as from solutions to a set of ratelike equations with coupling constants determined by the single-particle solutions to the time-dependent Dirac equation. This approach might be of relevance to the planned experiments to observe for the first time the laser-induced breakdown process of the vacuum.

The Journal (Wheel) Keeps On Turning, Bharath Sriraman

The Mathematics Enthusiast

No abstract provided.

Small Change - Big Difference, Ilana Lavy, Atara Shriki

The Mathematics Enthusiast

Starting in a well known theorem concerning medians of triangle and using the ‘What If Not?’ strategy, we describe an example of an activity in which some relations among segments and areas in triangle were revealed. Some of the relations were proved by means of Affine Geometry.

An Application Of Gröbner Bases, Shengxiang Xia, Gaoxiang Xia

The Mathematics Enthusiast

In this paper, we program a procedure using Maple's packages, with it we can realize mechanical proving of some theorems in elementary geometry.

Tme Volume 6, Number 3

The Mathematics Enthusiast

No abstract provided.

Who Can Solve 2x=1? An Analysis Of Cognitive Load Related To Learning Linear Equation Solving, Timo Tossavainen

The Mathematics Enthusiast

Using 2x = 1 as an example, we discuss the cognitive load related to learning linear equation solving. In the framework of the Cognitive Load Theory we consider especially the intrinsic cognitive load needed in arithmetical, geometrical and real analytical approach to linear equation solving. This will be done e.g. from the point of view of the conceptual and procedural knowledge of mathematics and the APOS Theory. Basing on our observations, in the end of the paper we design a setting for teaching linear equation solving.

Book Review: What's All The Commotion Over Commognition? A Review Of Anna Sfard's Thinking As Communicating, Bharath Sriraman

The Mathematics Enthusiast

If straight edge and compass constructions are the so-called “atoms” of Euclidean geometry, if sequences are the “atoms” of Analysis, then what are the “atoms” (if any) of mathematics education? Arguably mathematics education is a much wider field than Euclidean Geometry or Elementary Analysis, however there are several fundamental things that the field purports to study, chief among which is mathematical thinking or more generally “thinking”. The book under review, though it appears in a Cambridge University Press series entitled Learning in Doing: Social, Cognitive, and Computational Perspectives, is in my view situated at the intersection of Consciousness Studies, …

Report On The First International Workshop On Innovation In Digital Preservation (Indp 2009), Frank Mccown Ph.D., Hannes Kulovits, Andreas Rauber

Computer Science Faculty Research and Publications

Information about several topics discussed at the First International Workshop on Innovation in Digital Preservation (InDP 2009) on June 19, 2009 in Austin, Texas is presented. Topics include the collection of digital objects, web pages transition, and digital preservation (DP). The workshop featured presenters Rudolf Mayer, Martin Klein and Dominick Heutelbeck.

Assessment Of The Embodied Co2eq In Buildings Towards A Sustainable Building Design And Construction, Adolf Acquaye, Aidan Duffy, Biswajit Basu

Conference Papers

Research studies have shown that the initial energy embodied in a building can be as much as 67% of the operational energy over a 25 year period. With growing global concerns over material and resource consumption and the emissions of CO2 into the atmosphere, the energy embodied in buildings constructed in town and cities becomes important and one of the key issues that needs to be tackled in the design stages in order to strive towards sustainable buildings design. In this paper, a hybrid embodied carbon dioxide equivalent (CO2eq) methodology used to assess the CO2eq embodied in buildings is presented. …

Habitat Mapping In The Farasan Islands (Saudi Arabia) Using Casi And Quickbird Imagery, Gwilym Rowlands, James A. Goodman, Bernhard Riegl, Philip Renaud, Samuel J. Purkis

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Map products derived from remote sensing technology increase our understanding and ability to manage tropical marine environments. The enhanced mapping capabilities of hyperspectral sensors are well understood; yet technology uptake, particularly for large scale tasks, has been slow. The study presented represents one of the largest hyperspectral projects to date, and paves the way towards increased use of this technology. Hyperspectral CASI-550 imagery and multispectral QuickBird imagery, was acquired over 3,168 km² of the Farasan Islands. In addition to the typical image processing steps, inopportune water condensation in the CASI sensors lens necessitated further processing to remove an across-track …

Variability Timescales In The M87 Jet: Signatures Of E^2 Losses, Discovery Of A Quasi Period In Hst-1, And The Site Of Tev Flaring, Daniel E. Harris, Chi C. Cheung, Łukasz Stawarz, J. A. Biretta, Eric S. Perlman

Aerospace, Physics, and Space Science Faculty Publications

We investigate the variability timescales in the jet of M87 with two goals. The first is to use the rise times and decay times in the radio, ultraviolet, and X-ray light curves of HST-1 to constrain the source size and the energy loss mechanisms affecting the relativistic electron distributions. HST-1 is the first jet knot clearly resolved from the nuclear emission by Chandra and is the site of the huge flare of 2005. We find clear evidence for a frequency-dependent decrease in the synchrotron flux being consistent with E 2 energy losses. Assuming that this behavior is predominantly caused by …

Gluon-Spin Contribution To The Proton Spin From The Double-Helicity Asymmetry In Inclusive Π0 Production In Polarized P+P Collisions At Square Root Of S = 200 Gev, Andrew Marshall Adare, Sergey V. Afanasiev, Christine A. Aidala, N. N. Ajitanand, Yasuyuki Akiba, H. Al-Bataineh, Gyöngyi Baksay, László A. Baksay, Marcus Hohlmann, S. Rembeczki

Aerospace, Physics, and Space Science Faculty Publications

The double helicity asymmetry in neutral pion production for pT ¼ 1 to 12 GeV=c was measured with the PHENIX experiment to access the gluon-spin contribution, G, to the proton spin. Measured asymmetries are consistent with zero, and at a theory scale of 2 ¼ 4 GeV2 a next to leading order QCD analysis gives G½0:02;0:3 ¼ 0:2, with a constraint of 0:7 < G½0:02;0:3 < 0:5 at 2 ¼ 9 (3) for the sampled gluon momentum fraction (x) range, 0.02 to 0.3. The results are obtained using predictions for the measured asymmetries generated from four representative fits to polarized deep inelastic scattering data. We also consider the dependence of the G constraint on the choice of the theoretical scale, a dominant uncertainty in these predictions.

Near-Infrared Photoabsorption By C(60) Dianions In A Storage Ring, U. Kadhane, J. U. Andersen, E. Bonderup, B. Concina, P. Hvelplund, M. Kirketerp, B. Suhr, B. Liu, S. Bronsted Nielsen, S. Panja, J. Rangama, K. Stochkel, S. Tomita

Physics & Astronomy

We present a detailed study of the electronic structure and the stability of C(60) dianions in the gas phase. Monoanions were extracted from a plasma source and converted to dianions by electron transfer in a Na vapor cell. The dianions were then stored in an electrostatic ring, and their near-infrared absorption spectrum was measured by observation of laser induced electron detachment. From the time dependence of the detachment after photon absorption, we conclude that the reaction has contributions from both direct electron tunneling to the continuum and vibrationally assisted tunneling after internal conversion. This implies that the height of the …

Multipoint, High Time Resolution Galactic Cosmic Ray Observations Associated With Two Interplanetary Coronal Mass Ejections, Andrew P. Jordan, Harlan E. Spence, J. B. Blake, T. Mulligan, D. N. A. Shaul, M. Galametz

Physics & Astronomy

[1] Galactic cosmic rays (GCRs) play an important role in our understanding of the interplanetary medium (IPM). The causes of their short timescale variations, however, remain largely unexplored. In this paper, we compare high time resolution, multipoint space-based GCR data to explore structures in the IPM that cause these variations. To ensure that features we see in these data actually relate to conditions in the IPM, we look for correlations between the GCR time series from two instruments onboard the Polar and INTEGRAL (International Gamma Ray Astrophysical Laboratory) satellites, respectively inside and outside Earth's magnetosphere. We analyze the period of …

Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Annual Report, Period Ending July 1, 2009, Margaret N. Rees

Limnological Studies

Project 1: Eighteen advisory team meetings were attended this year; technical input was provided as appropriate; and summaries were prepared and delivered to Kent Turner. The SCOP Selenium Management Plan has been reviewed and a report is in preparation.

Project 2: A formal report titled, Surface Water Monitoring for Indicator Bacteria in High-use Sites of the Lake Mead National Recreation Area, was delivered in the second quarter of this year. Subsequently, a poster presentation on this topic was delivered at the Lake Mead Science Symposium and a manuscript has been prepared for submission to the journal, Lake and Reservoir Management. …

Lake Mead National Recreation Area Vegetation Monitoring And Analysis: Quarterly Progress Report, April 1, 2009 To June 30, 2009, Margaret N. Rees

Vegetation Monitoring

Executive Summary

• The Weed Sentry program surveyed over 187 miles (1,342 acres) of federal land by vehicle and foot in Clark County for incipient populations of exotic plants.
• Weed Sentry staff continue to survey never before surveyed sites, and trails and regions within Upper Las Vegas Wash CTA and Sloan Canyon NCA as requested by BLM managers
• In 2009 rare plant monitoring was completed. Data entry and analysis are in progress.

Mojave Applied Ecology Notes Summer 2009, Kevin E. Oliver, Dianne N. Bangle, E. Cayenne Engel, Lindsay P. Chiquoine, Scott R. Abella

Mojave Applied Ecology Notes

BLM and wildfire protection in the Mojave, studies of the sticky ringstem flowering phenology in Lake Mead NRA, restoration work within gypsum soils, post-fire response synthesis for Mojave and Sonoran deserts

How To Harness The Full Potential Of Integrated Catchment Management As A Pathway To Sustainability, Edward P. Weber, Ali Memon, Brett D. M. Painter

Public Policy and Leadership Faculty Publications

Water resource management authorities globally are increasingly adopting regional ecosystem approaches and reflexive governance as pathways to sustainable development (Paton et al., 2004; Vos et al.,2006). An integrated collaborative approach to natural resource management at the catchment scale is a strong theme in the recent literature (e.g., Lovell et al. 2002; Painter & Memon, 2008). New Zealand’s Resource Management Act (RMA), enacted in 1991, is a devolved planning mandate for
integrated natural resource management exercised by elected regional councils. The territorial jurisdiction of regional councils established in 1988 was purposely defined on the basis of groups of large water catchments …

Helping Teachers Un-Structure: A Promising Approach, Eric Hsu, Judy Kysh, Katherine Ramage, Diane Resek

The Mathematics Enthusiast

The amount of overt structure in the presentation of a task affects students’ engagement, creativity, and willingness to tolerate frustration. In a professional development project, with algebra teachers from nine American schools, we tried to help teachers make judicious decisions in their use of structure by having them facilitate low-structure tasks, remove structure from overly structured tasks, and observe “at-risk” students engaged in learning through low-structure tasks. Project schools that worked on structuring generally improved their algebra passing rates, both overall and for African-American students.

Intuitions Of "Infinite Numbers": Infinite Magnitude Vs. Infinite Representation, Ami Mamolo

The Mathematics Enthusiast

This study examines undergraduate students’ emerging conceptions of infinity as manifested in their engagement with geometric tasks. Students’ attempts to reduce the level of abstraction of infinity and properties of infinite quantities are described. Their arguments revealed they perceive infinity as an ongoing process, rather than a completed one, and fail to notice conflicting ideas. In particular, confusion between the infinite magnitude of points on a line segment and the infinite representation of real numbers was observed. Furthermore, students struggled to draw a connection between real numbers and their representation on a number line.

Fire Retardancy Of Bis[2-(Methacryloyloxy)Ethyl] Phosphate Modified Poly(Methyl Methacrylate) Nanocomposites Containing Layered Double Hydroxide And Montmorillonite, Linjiang Wang, Shengpei Shu, Dan Chen, Charles A. Wilkie

Chemistry Faculty Research and Publications

Copolymer nanocomposites were prepared by suspension copolymerization of bis[2-(methacryloyloxy)ethyl] phosphate and methyl methacrylate, together with bis(2-ethylhexyl) phosphate layered double hydroxide and a montmorillonite, Cloisite 93A. X-ray diffraction and transmission electron microscopy were used to characterize the morphology of nanocomposites and the dispersion of additives in the polymer. The thermal stability of the nanocomposites has been assessed by thermogravimetric analysis and cone calorimetry has been used to study the fire properties. Bis[2-(methacryloyloxy)ethyl] phosphate not only copolymerized with MMA, but also aids in the dispersion of additives in PMMA. The copolymer nanocomposites have better dispersion and higher degradation temperature and more char …