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2008

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Full-Text Articles in Physical Sciences and Mathematics

Wireless Intelligent Structural Health Monitoring System, Belle Ashwin Dec 2008

Wireless Intelligent Structural Health Monitoring System, Belle Ashwin

Theses and Dissertations

Metal structures are susceptible to various types of damages, including corrosion, stress damage, pillowing deformation, cracks etc. These kinds of damages in the metal structures occur mainly due to operational conditions and exposure to the environment. Our research involves a portable integrated wireless sensor system with video camera and ultrasound capabilities which is being developed to investigate corrosion damage on real structures in real time. This system uses images of the metal surfaces, which are captured from an integrated wireless sensor and then quantified and analyzed using computational intelligence. The quantification of the obtained images is done with specialized component …


Performance Analysis Of A Light Weight Packet Scanner, Paras Gandhi Dec 2008

Performance Analysis Of A Light Weight Packet Scanner, Paras Gandhi

Theses and Dissertations

The growth of networks around the world has also given rise to threats like viruses and Trojans. This rise in threats has resulted in counter measures for these threats. These counter measures are in the form of applications called firewalls or IDS. The incorporation of these applications in the network results in some delay in communications. The aim of the experiment in this thesis is to measure the delay introduced by such a firewall in the best case and compare it with the communication done on a network without such an application. These experiments are done using a special miniature …


Recursive Dispersion Relations In One-Dimensional Periodic Elastic Media, Ani P. Velo, George A. Gazonas, Erwin Bruder, Nancy Rodriguez Dec 2008

Recursive Dispersion Relations In One-Dimensional Periodic Elastic Media, Ani P. Velo, George A. Gazonas, Erwin Bruder, Nancy Rodriguez

Mathematics: Faculty Scholarship

A frequency bandgap is a range of wave frequencies that are prohibited from passing through a medium. The dispersion relation, which links the frequency to the wave number, enables us to illustrate the bandgaps. In [E. H. Lee, “A survey of variational methods for elastic wave propagation analysis in composites with periodic structures,” in Dynamics of Composite Materials, E. H. Lee, ed., ASME, New York, 1972, pp. 122–138] and [E. H. Lee and W. H. Yang, SIAM J. Appl. Math., 25 (1973), pp. 492–499] the dispersion relation was studied theoretically for the one-dimensional periodic structure made of two materials …


Using Geoscience Education Graduate Students To Help Faculty Transform Teaching Practice, Teagan L. Tomlin Dec 2008

Using Geoscience Education Graduate Students To Help Faculty Transform Teaching Practice, Teagan L. Tomlin

Theses and Dissertations

Universities make claims about student learning that graduates don't often achieve and are under pressure to show improvement in teaching and learning in their undergraduate programs. This has been the constant focus of university-level professional development programs, but most teachers are still not using the most effective teaching methods. Individual departments need to find ways to help their instructors overcome three main challenges associated with adopting more effective student-centered teaching methods. No matter what strategy is adopted, instructors need considerable support to 1) change their beliefs about what constitutes effective teaching and learning, 2) learn to effectively implement new strategies, …


Synthesis And Evaluation Of Structural Analogs Of Escherichia Coli Lipid A For Application Towards Cd14-Targeting Glycotherapeutics, Aileen Fay Galos Bongat Dec 2008

Synthesis And Evaluation Of Structural Analogs Of Escherichia Coli Lipid A For Application Towards Cd14-Targeting Glycotherapeutics, Aileen Fay Galos Bongat

Dissertations

Lipid A is a glucosamine-based phospholipid that anchors carbohydrate molecules to the outer membrane of most Gram-negative bacteria. During severe infection, this amphiphilic macromolecule invoke a strong and acute pro-inflammatory response that leads to sepsis and ultimately to septic shock, organ failure and death. Thus, following the convention that the best antidote is often a derivative of the parent agonistic molecule, researchers have actively pursued the idea of creating an analog of Lipid A that can block the cellular receptor for this molecule and thereby arrest the cascade of events that lead to sepsis. Consequently, we became interested in creating …


Collaborative Research: Geophysical Evaluation Of Biogenic Gasses In Peatlands, Andrew S. Reeve Dec 2008

Collaborative Research: Geophysical Evaluation Of Biogenic Gasses In Peatlands, Andrew S. Reeve

University of Maine Office of Research Administration: Grant Reports

Biogenic gas emission from northern peatlands, by wicking from vascular plants and by episodic ebullition events, accounts for approximately 7% of the global annual emission of methane to the atmosphere. This proposal involves experiments to apply ground penetrating radar (GPR) for (1) estimating the amount of biogenic gas stored in peatlands, (2) determining the spatial distribution of biogenic gas within the peat, and (3) monitoring biogenic gas release to the atmosphere. Data from a large northern peatland in Maine (EAR-0242353) show that (1) higher CH4 and CO2 concentrations correlate with high velocity/high attenuation zones in cross-borehole GPR data as well …


Chemistry's Essential Tensions: Three Views Of A Science, Roald Hoffmann Dec 2008

Chemistry's Essential Tensions: Three Views Of A Science, Roald Hoffmann

IMSA Great Minds Program ®

In this generously illustrated lecture several views of chemistry will be presented, stressing its psychological dimension and its tie to the arts: First of all, chemistry is, as it has always been, the art, craft, business of substances and their transformations. It is now also the science of microscopic molecules, both simple and complex. And then there are people’s perceptions of chemistry - alternating between seeing the healing and the hurting aspects of this truly anthropic science. The underlying psychological tensions of this truly anthropic science will be explored.


Transforming Water: Water Efficiency As Stimulus And Long‐Term Investment, David Mitchell, Janice Beecher, Thomas Chesnutt, David Pekelney Dec 2008

Transforming Water: Water Efficiency As Stimulus And Long‐Term Investment, David Mitchell, Janice Beecher, Thomas Chesnutt, David Pekelney

Publications (WR)

Water Efficiency programs have an established track record as cost‐effective long‐term public resource investments. Less well understood are the short‐term economic impacts of these rapidly scalable and adaptable programs, and the ability of these programs to quickly deliver economic benefit as well as sustainable solutions. This paper quantitatively examines the short‐term economic growth impacts of water/energy efficiency investments, specifically in terms of job creation, income, GDP, national output, water savings, and other benefits.

Our consultant team modeled a wide range of water/energy efficiency program possibilities, across all water‐using sectors and involving indoor, outdoor, and water system efficiencies. This modeling clearly …


Locality And Stability Of The Cascades Of Two-Dimensional Turbulence, Eleftherios Gkioulekas Dec 2008

Locality And Stability Of The Cascades Of Two-Dimensional Turbulence, Eleftherios Gkioulekas

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

We investigate and clarify the notion of locality as it pertains to the cascades of two-dimensional turbulence. The mathematical framework underlying our analysis is the infinite system of balance equations that govern the generalized unfused structure functions, first introduced by L’vov and Procaccia. As a point of departure we use a revised version of the system of hypotheses that was proposed by Frisch for three-dimensional turbulence. We show that both the enstrophy cascade and the inverse energy cascade are local in the sense of nonperturbative statistical locality. We also investigate the stability conditions for both cascades. We have shown that …


The Thermoelectric Properties Investigation Of X0.05Mo3Sb7-YTeY (X=Mn, Fe, Ni, Co; Y=1.5, 1.6, 1.7), Tim Holgate Dec 2008

The Thermoelectric Properties Investigation Of X0.05Mo3Sb7-YTeY (X=Mn, Fe, Ni, Co; Y=1.5, 1.6, 1.7), Tim Holgate

All Theses

With ever increasing energy costs, dwindling resources, and terms with the prefix 'green' filling headlines, the need for environmentally friendly energy sources has never been greater. Since the mid-20th century researchers have been pursuing greater efficiency in thermoelectric materials. Thermoelectric materials achieve energy conversion via the Seebeck effect (heat to electric power) and the Peltier effect (electricity to cooling power). Presented herein are the measured electrical and thermal transport properties and phenomenal analysis of the Ir3Ge7-type system: X0.05Mo3Sb7-yTey (X=Mn, Fe, Ni, Co; y=1.5, 1.6, 1.7) where 'X' are interstitially …


Choosing Among Unequals: A Statistical Solution To A Stalemate, Durgesh Chandra Pathak Dec 2008

Choosing Among Unequals: A Statistical Solution To A Stalemate, Durgesh Chandra Pathak

Durgesh Chandra Pathak

In Uttar Pradesh, a new tradition has been started of selecting B.Ed degree holders for a job in Primary Schools and it has been named "Vishisht BTC". Applying their own logic, the ruling governments use variuos criterion to select the candidates. The basic problem is that they have to choose candidates on the basis of merit of their marks in various exams. Now, it is well-established fact that marking is not similar in all universities/colleges. So for a same exam, there can be much inter-university as well as intra-university variation in marks given to students. The point is that student …


Giant Sequoia Insect, Disease, And Ecosystem Interactions, Douglas D. Piirto Dec 2008

Giant Sequoia Insect, Disease, And Ecosystem Interactions, Douglas D. Piirto

Douglas D. Piirto

Individual trees of giant sequoia (Sequoia gigantea [Lindl.] Decne.) have demonstrated a capacity to attain both a long life and very large size. It is not uncommon to find old-growth giant sequoia trees in their native range that are 1,500 years old and over 15 feet in diameter at breast height. The ability of individual giant sequoia trees to survive over such long periods of time has often been attributed to the species high resistance to disease, insect, and fire damage. Such a statement, however, is a gross oversimplification, given broader ecosystem and temporal interactions. For example, why isn't there …


Efficacy Of Herbicide Application Methods Used To Control Tanoak (Lithocarpus Densiflorus) In An Uneven-Aged Coast Redwood Management Context, Douglas D. Piirto, Brenda Smith, Eric K. Huff, Scott T. Robinson Dec 2008

Efficacy Of Herbicide Application Methods Used To Control Tanoak (Lithocarpus Densiflorus) In An Uneven-Aged Coast Redwood Management Context, Douglas D. Piirto, Brenda Smith, Eric K. Huff, Scott T. Robinson

Douglas D. Piirto

Three methods of tanoak (Lithocarpus densiflorus [Hook. & Arn.] Rehd.) control involving the application of the amine or ester form of triclopyr were evaluated in this coast redwood uneven-aged forest management study of herbicides. A cut-stump application with the amine form of triclopyr (Garlon 3A), frill cut with the amine form of triclopyr, basal-bark (outer surface) with the ester form of triclopyr (Garlon 4), and an untreated control were replicated three times. The tanoak control results in Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) and/ or coast redwood (Sequoia sempervirens [D. Don] Endl.) predominated stands obtained in earlier studies …


Cost-Effective Fire Management For Southern California's Chaparral Wilderness: An Analytical Procedure, Chris A. Childers, Douglas D. Piirto Dec 2008

Cost-Effective Fire Management For Southern California's Chaparral Wilderness: An Analytical Procedure, Chris A. Childers, Douglas D. Piirto

Douglas D. Piirto

Fire management has always meant fire suppression to the managers of the chaparral covered southern California National Forests. Today, Forest Service fire management programs must be cost effective, while wilderness fire management objectives are aimed at recreating natural fire regimes. A cost-effectiveness analysis has been developed to compare fire management options for meeting these objectives in California's chaparral wilderness. This paper describes the analytical procedure using examples from a study currently being conducted for the Los Padres National Forest, and discusses some preliminary results.


The Birge Sponer Extrapolation, Carl W. David Dec 2008

The Birge Sponer Extrapolation, Carl W. David

Chemistry Education Materials

The Birge Sponer extrapolation is explained using examples.


Contamination Cannot Explain The Lack Of Large-Scale Power In The Cosmic Microwave Background Radiation, Emory F. Bunn, Austin Bourdon Dec 2008

Contamination Cannot Explain The Lack Of Large-Scale Power In The Cosmic Microwave Background Radiation, Emory F. Bunn, Austin Bourdon

Physics Faculty Publications

Several anomalies appear to be present in the large-angle cosmic microwave background (CMB) anisotropy maps of the Wilkinson Microwave Anisotropy Probe. One of these is a lack of large-scale power. Because the data otherwise match standard models extremely well, it is natural to consider perturbations of the standard model as possible explanations. We show that, as long as the source of the perturbation is statistically independent of the source of the primary CMB anisotropy, no such model can explain this large-scale power deficit. On the contrary, any such perturbation always reduces the probability of obtaining any given low value of …


Statistics Of Auroral Langmuir Waves, M. Samara, J. Labelle, I. H. Cairns Dec 2008

Statistics Of Auroral Langmuir Waves, M. Samara, J. Labelle, I. H. Cairns

Dartmouth Scholarship

The Physics of Auroral Zone Electrons II (PHAZE II) sounding rocket was launched in February 1997 into active pre-midnight aurora. The resulting high frequency wave data are dominated by Langmuir waves. Consistent with many previous observations the Langmuir waves are sporadic, occurring in bursts lasting up to a few hundred ms. We compute statistics of the electric field amplitudes of these Langmuir waves, with two results. First, the shape of the distribution of running averages of the electric field amplitudes remains approximately stationary for a large range of widths of running average less than ~0.3 ms and for a large …


Developing Real Time Applications With Java Based Sun Spot, L. Chen, Phillip J. Mckerrow, Q. Lu Dec 2008

Developing Real Time Applications With Java Based Sun Spot, L. Chen, Phillip J. Mckerrow, Q. Lu

Faculty of Informatics - Papers (Archive)

Most researchers develop real-time applications with C, including programming hardware with C and using a Real Time Operating System (RTOS) that is written in C to manage the task environment. In this paper, we research a different approach by using Java to develop a real-time application. We implement an example real-time project, onboard computation of a coaxial helicopter Lama, with a Java based Sun SPOT to control the hardware and a Java RTOS (JARTOS) running on top of the Sun SPOT to manage the processes. This project enables us to answer several questions regarding to real-time system development with the …


Suppression Pattern Of Neutral Pions At High Transverse Momentum In Au + Au Collisions At Square Root Of Snn = 200 Gev And Constraints On Medium Transport Coefficients, Andrew Marshall Adare, Sergey V. Afanasiev, Christine A. Aidala, N. N. Ajitanand, Yasuyuki Akiba, Gyöngyi Baksay, László A. Baksay, Marcus Hohlmann, S. Rembeczki, Klaus Dehmelt Dec 2008

Suppression Pattern Of Neutral Pions At High Transverse Momentum In Au + Au Collisions At Square Root Of Snn = 200 Gev And Constraints On Medium Transport Coefficients, Andrew Marshall Adare, Sergey V. Afanasiev, Christine A. Aidala, N. N. Ajitanand, Yasuyuki Akiba, Gyöngyi Baksay, László A. Baksay, Marcus Hohlmann, S. Rembeczki, Klaus Dehmelt

Aerospace, Physics, and Space Science Faculty Publications

For Au þ Au collisions at 200 GeV, we measure neutral pion production with good statistics for transverse momentum, pT, up to 20 GeV=c. A fivefold suppression is found, which is essentially constant for 5 < pT < 20 GeV=c. Experimental uncertainties are small enough to constrain any model-dependent parametrization for the transport coefficient of the medium, e.g., hq^i in the parton quenching model. The spectral shape is similar for all collision classes, and the suppression does not saturate in Au þ Au collisions.


Resonance Raman Interrogation Of The Consequences Of Heme Rotational Disorder In Myoglobin And Its Ligated Derivatives, Freeborn Rwere, Piotr J. Mak, James R. Kincaid Dec 2008

Resonance Raman Interrogation Of The Consequences Of Heme Rotational Disorder In Myoglobin And Its Ligated Derivatives, Freeborn Rwere, Piotr J. Mak, James R. Kincaid

Chemistry Faculty Research and Publications

Resonance Raman spectroscopy is employed to characterize heme site structural changes arising from conformational heterogeneity in deoxyMb and ligated derivatives, i.e., the ferrous CO (MbCO) and ferric cyanide (MbCN) complexes. The spectra for the reversed forms of these derivatives have been extracted from the spectra of reconstituted samples. Dramatic changes in the low-frequency spectra are observed, where newly observed RR modes of the reversed forms are assigned using protohemes that are selectively deuterated at the four methyl groups or at the four methine carbons. Interestingly, while substantial changes in the disposition of the peripheral vinyl and propionate groups can be …


Dynamic Ordering Transitions Of Liquid Crystals Driven By Interfacial Complexes Formed Between Polyanions And Amphiphilic Polyamines, Michael I. Kinsinger, Maren E. Buck, Fernando Campos, David M. Lynn, Nicholas L. Abbott Dec 2008

Dynamic Ordering Transitions Of Liquid Crystals Driven By Interfacial Complexes Formed Between Polyanions And Amphiphilic Polyamines, Michael I. Kinsinger, Maren E. Buck, Fernando Campos, David M. Lynn, Nicholas L. Abbott

Chemistry: Faculty Publications

We report the design of an amphiphilic polyamine (polymer 1) based on poly(2-alkenyl azlactone) that strongly couples the formation of polyelectrolyte complexes at aqueous/liquid crystal (LC) interfaces to ordering transitions in the LC. We demonstrate that the addition of a strong anionic polyelectrolyte to aqueous solutions in contact with polymer 1-laden LC interfaces (prepared by Langmuir-Schaefer transfer of monolayers of polymer 1 onto micrometerthick films of nematic LC) triggers ordering transitions in the LCs. We further demonstrate that changes in the ordering of the LCs (i) are driven by electrostatic interactions between the polyelectrolytes, (ii) involve multivalent interactions between the …


Correction Of Electronic Record For Weighing Bucket Precipitation Gauge Measurements, Anurag Nayak, David G. Chandler, Danny Marks, James P. Mcnamara, Mark Seyfried Dec 2008

Correction Of Electronic Record For Weighing Bucket Precipitation Gauge Measurements, Anurag Nayak, David G. Chandler, Danny Marks, James P. Mcnamara, Mark Seyfried

Geosciences Faculty Publications and Presentations

Electronic sensors generate valuable streams of forcing and validation data for hydrologic models but are often subject to noise which must be removed as part of model input and testing database development. We developed an automated precipitation correction program (APCP) for weighing bucket precipitation gauge records, which are subject to several types of mechanical and electronic noise and discontinuities, including gauge maintenance, missing data, wind vibration, and sensor drift. Corrected cumulative water year precipitation from APCP did not exhibit an error bias and matched measured water year total precipitation within 2.1% for 58 station years tested. Removal of low-amplitude periodic …


Simulation And Analysis Of Cadmium Sulfide Nanoparticles, Chad Everett Junkermeier Dec 2008

Simulation And Analysis Of Cadmium Sulfide Nanoparticles, Chad Everett Junkermeier

Theses and Dissertations

I used ab initio molecular dynamics calculations to model cadmium sulfide nanoparticles. The nanoparticles were originaly spherical, bulk-like zinc-blende structures. Constant temperature molecular dynamics calculations reveals that CdS nanoparticles that are about 2 nm in diameter and have unpassivated surfaces are in an amorphous structure with short range order. The nearest neighbor distance on the surface of the nanoparticles being near the wurtzite nearest neighbor distance. I wrote the program xyzSTATS and used its results in justifying the amorphous nanoparticles claim. I also estimated the band gap of the CdS nanoparticles with unpassivated dangling bonds.


Book I, Otto Vogl: Papers And Patents, 1948-1970, Jane C. Vogl Dec 2008

Book I, Otto Vogl: Papers And Patents, 1948-1970, Jane C. Vogl

Emeritus Faculty Author Gallery

Books I-XII include citations to Otto Vogl's publications and patents. Printed versions of these twelve volumes are also available in the Integrated Sciences and Engineering Library of the University of Massachusetts in Amherst. MA, Lederle Graduate Research Center. The printed volumes include the full reprints of all cited publications.


Centers Of Polymer Science: Introduction, Otto Vogl Dec 2008

Centers Of Polymer Science: Introduction, Otto Vogl

Emeritus Faculty Author Gallery

Centers of Polymer Science describes polymer research activities taking place in Europe, Asia, and Australia primarily during the years between 1980 and 2000. This series of articles shows and records the activity in Polymer Science in this part of polymer history.


Hydrochemistry Of Wetlands Along The Platte River Near Ashland, Nebraska, Carrie L. Wiese Dec 2008

Hydrochemistry Of Wetlands Along The Platte River Near Ashland, Nebraska, Carrie L. Wiese

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Structural And Magnetic Properties Of Manganites Pr1-XCa1+XMno4, Oxypnictides Cefeaso1-XFX, And Filled Skutterudite Pros4As12, Songxue Chi Dec 2008

Structural And Magnetic Properties Of Manganites Pr1-XCa1+XMno4, Oxypnictides Cefeaso1-XFX, And Filled Skutterudite Pros4As12, Songxue Chi

Doctoral Dissertations

We present neutron scattering, with triple-axis and time-of-flight spectrometers, to study the structural and magnetic properties of the layered manganites Pr1-xCa1+xMnO4 (PCMO), and to determine the crystalline electric field (CEF) levels in iron pnictides CeFeAsO1-xFx and filled skutterudite compound PrOs4As12.

For the single-layered manganites PCMO, four dopings (x=0.5, 0.45, 0.40 and 0.35) have been studied. At half-doping, the system first becomes charge- and orbital- ordered (CO/OO) near TCO = 300 K and then develops CE-type antiferromagnetic (AF) order below TN = 130 K. …


Explicit Methods In The Nuclear Burning Problem For Supernova Ia Models, Viktor Chupryna Dec 2008

Explicit Methods In The Nuclear Burning Problem For Supernova Ia Models, Viktor Chupryna

Doctoral Dissertations

Most modern astrophysical problems such as supernova simulation require application of state-ofthe- art computational tools. Despite the fact that number of nuclei included in coupled simulations tends to be small, problems such as nuclear burning networks are often part of a large set of interconnected programs that require significant computing resources. Expansion of the nuclear reaction network to realistic sizes can easily make element and energy production the leading consumer of both time and memory in simulations. Therefore, in solving nuclear reaction networks coupled to (radiation) hydrodynamics in astrophysics simulations, the development of methods capable of improving on the traditional …


Adsorption Of Propane On The Magnesium Oxide (100) Surface And Synthesis Of Anodized Aluminum Oxide, Michael John Felty Dec 2008

Adsorption Of Propane On The Magnesium Oxide (100) Surface And Synthesis Of Anodized Aluminum Oxide, Michael John Felty

Doctoral Dissertations

This work is divided into two parts: the adsorption of propane on the magnesium oxide (100) surface and the synthesis of anodized aluminum oxide. The adsorption properties of propane on the MgO (100) surface were investigated using high-resolution volumetric isotherm techniques and a computational study was accomplished using Materials Studio. From the adsorption work, the two-dimensional isothermal compressibility, the isosteric heat of adsorption, the differential enthalpy, and the differential entropy of adsorption can be calculated. Three distinct layers of propane were observed to form on the MgO (100) surface and it was determined that a phase transition occurs at 162 …


Molecular Hydrogen Adsorbed On Mgo (100) Surfaces: A Thermodynamic Study, Lillian Ruth Frazier Dec 2008

Molecular Hydrogen Adsorbed On Mgo (100) Surfaces: A Thermodynamic Study, Lillian Ruth Frazier

Doctoral Dissertations

The thermodynamics of molecular hydrogen adsorbed on MgO (100) surfaces has been examined using high resolution volumetric adsorption isotherm techniques. These studies were undertaken using highly perfect, narrow size distributed MgO nanocubes with essentially single (100) facet exposure and extremely high chemical purity. A narrowly spaced (in temperature) series of isotherms were performed between the temperatures of ~7K and the triple point (13.8 K) using H2 and D2 gas.

A minimum of five, and in some cases seven, discrete adsorption steps are clearly observed in each isotherm trace. Analysis of these data indicate that the monolayer film forms …