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Using A Computer Simulation To Teach Science Process Skills To College Biology And Elementary Majors, Aimée T. Lee, Rosalina V. Hairston, Rachel Thames, Tonya Lawrence, Sherry S. Herron Dec 2002

Using A Computer Simulation To Teach Science Process Skills To College Biology And Elementary Majors, Aimée T. Lee, Rosalina V. Hairston, Rachel Thames, Tonya Lawrence, Sherry S. Herron

Faculty Publications

The Lateblight computer simulation (Arneson and Ticknor, 1990) has been implemented in the general biology laboratory and the science methods course for elementary teachers to reinforce the processes of science and to allow the students to engage, explore, explain, elaborate and evaluate the methods of building concepts in science. The students develop testable hypotheses and then use the program to run experiments and collect data. In addition, they research relevant background information and subsequently present their results in a poster during class.

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Urinary Excretion Of Dithiocarbamates And Selfreported Cruciferous Vegetable Intake: Application Of The ‘Method Of Triads’ To A Foodspecific Biomarker, Jay H. Fowke, James R. Hébert, Jed W. Fahey Dec 2002

Urinary Excretion Of Dithiocarbamates And Selfreported Cruciferous Vegetable Intake: Application Of The ‘Method Of Triads’ To A Foodspecific Biomarker, Jay H. Fowke, James R. Hébert, Jed W. Fahey

Faculty Publications

Objective: Greater intake of Cruciferous vegetables (e.g. broccoli) may prevent cancer at several sites. Urinary excretion of isothiocyanate conjugates (dithiocarbamates, DTC) provides a specific biomarker of Cruciferous vegetable consumption suitable for epidemiological investigations. However, no gold-standard referent is available for evaluating urinary DTC levels as an estimator of Cruciferous vegetable consumption. We compared urinary DTC levels to intake as measured by two selfreported dietary assessment techniques. Design: Cruciferous vegetable consumption was measured before and after a behavioural dietary intervention using multiple 24-hour recalls (24HR), a foodcounting questionnaire (VFQ) and urinary DTC excretion levels. Analysis included a structural equation approach (Method …

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Properties Of Hadronic Final States In Diffractive Deep Inelastic Ep Scattering At Desy Hera, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli Dec 2002

Properties Of Hadronic Final States In Diffractive Deep Inelastic Ep Scattering At Desy Hera, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli

Faculty Publications

Characteristics of the hadronic final state of diffractive deep inelastic scattering events ep→eXp were studied in the kinematic range 4X35GeV, 4

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Searches For Excited Fermions In Ep Collisions At Hera, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli Nov 2002

Searches For Excited Fermions In Ep Collisions At Hera, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli

Faculty Publications

Searches in ep collisions for heavy excited fermions have been performed with the ZEUS detector at HERA. Excited states of electrons and quarks have been searched for in e+ p collisions at a centre-of-mass energy of 300 GeV using an integrated luminosity of 47.7 pb-1. Excited electrons have been sought via the decays e± → eγ, e± → eZ and e± → vW. Excited quarks have been sought via the decays q± → qγ and q± → qW. A search for excited neutrinos decaying via v± → vγ, v± → vZ and v± → eW is presented using e-p collisions …

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Embedding Dissipation And Decoherence In Unitary Evolution Schemes, A. R.P. Rau, R. A. Wendell Nov 2002

Embedding Dissipation And Decoherence In Unitary Evolution Schemes, A. R.P. Rau, R. A. Wendell

Faculty Publications

The dissipation and decoherence in unitary evolution schemes of quantum physics was discussed. The master equations of damped, driven two-level system were used in the density matrix. The elements of density matrix were embedded in higher-dimensional Liouville-Bloch equations. The density matrix was solved as a function of time using nonunitary integration.

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A Quantum Rosetta Stone For Interferometry, Hwang Lee, Pieter Kok, Jonathan P. Dowling Nov 2002

A Quantum Rosetta Stone For Interferometry, Hwang Lee, Pieter Kok, Jonathan P. Dowling

Faculty Publications

Heisenberg-limited measurement protocols can be used to gain an increase in measurement precision over classical protocols. Such measurements can be implemented using, for example, optical Mach-Zehnder interferometers and Ramsey spectroscopes. We address the formal equivalence between the Mach-Zehnder interferometer, the Ramsey spectroscope and a generic quantum logic circuit. Based on this equivalence we introduce the 'quantum Rosetta stone', and we describe a projective-measurement scheme for generating the desired correlations between the interferometric input states in order to achieve Heisenberg-limited sensitivity. The Rosetta stone then tells us that the same method should work in atom spectroscopy.

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Seasonality Of Dissolved Rare Earth Elements In The Lower Mississippi River, Alan M. Shiller Nov 2002

Seasonality Of Dissolved Rare Earth Elements In The Lower Mississippi River, Alan M. Shiller

Faculty Publications

[1] Dissolved rare earth element (REE) concentrations were determined in a 27-month time series of the lower Mississippi River. Overall, the results agree with limited previous investigations; that is, the river shows enrichment of heavy REEs relative to light REEs and also has a significant Ce anomaly. However, the previous investigations relied on only single samples from the river. This seasonal investigation reveals significant temporal variations in the river's REE chemistry. In particular, large ( approximately fivefold) variations in light REE concentrations are observed. The light REEs follow a seasonality similar to particle-reactive trace elements. Also, the Ce anomaly shows …

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Statistical Cataloging Of Archival Data For Luminosity Class Iv-V Stars, B. J. Taylor Nov 2002

Statistical Cataloging Of Archival Data For Luminosity Class Iv-V Stars, B. J. Taylor

Faculty Publications

This paper is one of a pair in which temperatures and metallicity catalogs for class IV-V stars are considered. The temperature catalog described here is derived from a calibration based on stellar angular diameters. If published calibrations of this kind are compared by using color-index transformations, temperature-dependent differences among the calibrations are commonly found. However, such differences are minimized if attention is restricted to calibrations based on Johnson V-K. A calibration of this sort from Di Benedetto (1998) is therefore tested and adopted. That calibration is then applied to spectroscopic and photometric data, with the latter predominating. Cousins R-I photometry …

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Statistical Cataloging Of Archival Data For Luminosity Class Iv-V Stars - Ii. The Epoch 2001 [Fe/H] Catalog, B. J. Taylor Nov 2002

Statistical Cataloging Of Archival Data For Luminosity Class Iv-V Stars - Ii. The Epoch 2001 [Fe/H] Catalog, B. J. Taylor

Faculty Publications

This paper describes the derivation of an updated statistical catalog of metallicities. The stars for which those metallicities apply are of spectral types F, G, and K, and are on or near the main sequence. The input data for the catalog are values of [Fe/H] published before 2002 February and derived from lines of weak and moderate strength. The analyses used to derive the data have been based on one-dimensional LTE model atmospheres. Initial adjustments which are applied to the data include corrections to a uniform temperature scale which is given in a companion paper (see Taylor 2003). After correction, …

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Inclusive Jet Cross Sections In The Breit Frame In Neutral Current Deep Inelastic Scattering At Hera And Determination Of Α S, S. Chekanov, D. Krakauer, S. Magill, B. Musgrave, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, A. Margotti, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli, A. Zichichi, G. Aghuzumtsyan, D. Bartsch, I. Brock Nov 2002

Inclusive Jet Cross Sections In The Breit Frame In Neutral Current Deep Inelastic Scattering At Hera And Determination Of Α S, S. Chekanov, D. Krakauer, S. Magill, B. Musgrave, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, A. Margotti, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli, A. Zichichi, G. Aghuzumtsyan, D. Bartsch, I. Brock

Faculty Publications

Inclusive jet differential cross sections have been measured in neutral current deep inelastic e +p scattering for boson virtualities Q 2 > 125 GeV 2. The data were taken using the ZEUS detector at HERA and correspond to an integrated luminosity of 38.6 pb -1. Jets were identified in the Breit frame using the longitudinally invariant k T cluster algorithm. Measurements of differential inclusive jet cross sections are presented as functions of jet transverse energy (E BT.jet), jet pseudorapidity and Q 2, for jets with E BT.jet > 8 GeV. Next-to-leading-order QCD calculations agree well with the measurements both at high Q …

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Nitrogen Loading Into An Urban Estuary: Lake Pontchartrain (Louisiana, U.S.A.), R. Eugene Turner, Q. Dortch, Dubravko Justic, Erick M. Swenson Nov 2002

Nitrogen Loading Into An Urban Estuary: Lake Pontchartrain (Louisiana, U.S.A.), R. Eugene Turner, Q. Dortch, Dubravko Justic, Erick M. Swenson

Faculty Publications

We constructed a nitrogen loading budget for the Lake Pontchartrain watershed located north of New Orleans, Louisiana (U.S.A.). Water quality measurements, discharge estimates, and literature values were used to establish the annual and seasonal variations in loading rates for total nitrogen and nitrate. The relatively stable annual loadings (million kg N) are about 10× that of the pre-settlement nitrogen loading, and come from atmosphere (1.3), the watershed (7.8), pumped urban runoff from New Orleans (1.0), and leakage through the Bonnet Carré flood control structure (0.5–0.9). Relatively minor additional amounts come from nitrogen fixation in the Lake. Occasional openings of the …

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The Cauchy Problem And Stability Of Solitary-Wave Solutions For Rlw-Kp-Type Equations, Jerry L. Bona, Yue Liu, Michael M. Tom Nov 2002

The Cauchy Problem And Stability Of Solitary-Wave Solutions For Rlw-Kp-Type Equations, Jerry L. Bona, Yue Liu, Michael M. Tom

Faculty Publications

The Kadomtsev-Petviashvilli (KP) equation, (ut + ux + uux + uxxx )x + euyy = 0, (*) arises in various contexts where nonlinear dispersive waves propagate principally along the x-axis, but with weak dispersive effects being felt in the direction parallel to the y-axis perpendicular to the main direction of propagation. We propose and analyze here a class of evolution equations of the form (ut + ux, + upux + Lut)x + euyy = 0, (* *) which provides an alternative to Eq. (*) in the same way the regularized long-wave equation is related to the classical Korteweg-de …

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The Design And Evaluation Of Interactivities In A Digital Library, Muniram Budhu, Anita Coleman Nov 2002

The Design And Evaluation Of Interactivities In A Digital Library, Muniram Budhu, Anita Coleman

Faculty Publications

The US National Science Foundation has established a program to create a National Science, Mathematics, Engineering and Technology Education Digital Library (NSDL). One of the subsidiary NSDL libraries under development is the National Civil Engineering Educational Resources Library (NCERL). The first phase of NCERL is the creation and collection of digital resources in three areas of civil engineering—geotechnical (soil), rock, and water engineering (GROW). The concept of interactivities guides the design, development, and evaluation efforts of the GROW digital collection. This article describes the salient features of GROW, defines and discusses interactivities as an emerging, integral part of teaching and …

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Modeling The Multicast Address Allocation Problem, Daniel Zappala, Chris Gauthierdickey, Virginia Lo Nov 2002

Modeling The Multicast Address Allocation Problem, Daniel Zappala, Chris Gauthierdickey, Virginia Lo

Faculty Publications

To support IP multicast, domains must assign a unique multicast address to each application from a limited, globally-shared address space. We examine the performance of several classes of address allocation algorithms withln the context of the MASC architecture. This study is the first of its kind to model the generalized multicast address allocation problem and consider non-contiguous allocation algorithms. We find that prefix-based allocation outperforms our non-contiguous algorithm, despite the apparent advantages of non-contiguous allocation. We also verify the benefits of using worst-fit for new allocations.

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Analysis Of Vesicular Basalts And Lava Emplacement Processes For Application As A Paleobarometer/Paleoaltimeter, Dork L. Sahagian, Alexander A. Prusevich, William D. Carlson Nov 2002

Analysis Of Vesicular Basalts And Lava Emplacement Processes For Application As A Paleobarometer/Paleoaltimeter, Dork L. Sahagian, Alexander A. Prusevich, William D. Carlson

Faculty Publications

We have developed a method for determining paleoelevations of highland areas on the basis of the vesicularity of lava flows. Vesicular lavas preserve a record of paleopressure at the time and place of emplacement because the difference in internal pressure in bubbles at the base and top of a lava flow depends on atmospheric pressure and lava flow thickness. At the top of the flow, the pressure is simply atmospheric pressure, while at the base, there is an additional contribution of hydrostatic lava overburden. Thus the modal size of the vesicle (bubble) population is larger at the top than at …

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A Theoretical Framework For The Multicast Address Allocation Problem, Daniel Zappala, Chris Gauthierdickey, Virginia Lo, Timothy Singer Nov 2002

A Theoretical Framework For The Multicast Address Allocation Problem, Daniel Zappala, Chris Gauthierdickey, Virginia Lo, Timothy Singer

Faculty Publications

The multicast address allocation problem requires Internet domains to allocate unique addresses to multicast applications from a globally-shared space. We develop a theoretical framework for multicast allocation algorithms that is influenced by subcube allocation in hypercube computer systems. Based on this framework we derive complexity results for the address allocation problem and describe several new allocation algorithms that use a hypercube model for address representation.

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Distributions Of Nobel Metal Pd And Pt In Mesoporous Silica, J. Arbiol, A. Cabot, J. R. Morante, Fanglin Chen, Meilin Liu Oct 2002

Distributions Of Nobel Metal Pd And Pt In Mesoporous Silica, J. Arbiol, A. Cabot, J. R. Morante, Fanglin Chen, Meilin Liu

Faculty Publications

Mesoporous silicananostructures have been synthesized and loaded with Pd and Pt catalytic noble metals. It is found that Pd forms small nanoclusters (3–5 nm) on the surface of the mesoporous structure whereas Pt impregnation results in the inclusion of Pt nanostructures within the silica hexagonal pores (from nanoclusters to nanowires). It is observed that these materials have high catalyticproperties for CO–CH4CO–CH4CO–CH4 combustion, even in a thick film form. In particular, results indicate that the Pt and Pd dispersed in mesoporous silica are catalytically active as a selective filter for gas sensors.

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Horizon Occlusion Culling For Real-Time Rendering Of Hierarchical Terrains, Parris K. Egbert, Brandon Lloyd Oct 2002

Horizon Occlusion Culling For Real-Time Rendering Of Hierarchical Terrains, Parris K. Egbert, Brandon Lloyd

Faculty Publications

We present a technique to perform occlusion culling for hierarchical terrains at run-time. The algorithm is simple to implement and requires minimal pre-processing and additional storage, yet leads to 2-4 times improvement in framerate for views with high degrees of occlusion. Our method is based on the well-known occlusion horizon algorithm. We show how to adapt the algorithm for use with hierarchical terrains. The occlusion horizon is constructed as the terrain is traversed in an approximate front to back ordering. Regions of the terrain are compared to the horizon to determine when they are completely occluded from the viewpoint. Culling …

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Volcanic Mound Fields On The East Pacific Rise, 16˚-19˚S: Low Effusion Rate Eruptions At Overlapping Spreading Centers For The Past 1 Myr, Scott M. White, Ken C. Macdonald, John Sinton Oct 2002

Volcanic Mound Fields On The East Pacific Rise, 16˚-19˚S: Low Effusion Rate Eruptions At Overlapping Spreading Centers For The Past 1 Myr, Scott M. White, Ken C. Macdonald, John Sinton

Faculty Publications

Volcanic mound fields identified on SeaMARC II and HMR1 12 kHz side-scan data from the southern East Pacific Rise (SEPR) occur near overlapping spreading centers (OSCs) and migration traces of OSCs. The volcanic mound fields appear as a distinctive hummocky seafloor fabric due to side-scan backscatter reflections from clusters of moundshaped reflectors. The lack of growth of the mound fields away from the ridge axis, and their occurrence in association with OSC traces, suggests that mound fields form along the ridge crest near OSCs. Volcanic mound fields are found where 120 kHz side-scan and visual observations find fields of pillow …

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Rf Rendez-Blue: Reducing Power And Inquiry Costs In Bluetooth-Enabled Mobile Systems, Eric S. Hall, Charles D. Knutson, David K. Vawdrey Oct 2002

Rf Rendez-Blue: Reducing Power And Inquiry Costs In Bluetooth-Enabled Mobile Systems, Eric S. Hall, Charles D. Knutson, David K. Vawdrey

Faculty Publications

In resource-limited mobile computing devices, Bluetooth wireless technology imposes a weighty burden due to inefficient power utilization and a sluggish device discovery process. Buttressing Bluetooth with Radio Frequency Identification (RFID) technology by performing an operation we call “Rendez-Blue” alleviates these limitations. In the Rendez-Blue process, an RFID signal is used as a cue to “wake-up” a sleeping Bluetooth radio. This ensures that the Bluetooth radio is active only when needed, significantly reducing power consumption. In addition, RFID is used to communicate Bluetooth device information, allowing the user to bypass the traditional 10.24-second discovery process.

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Measurement Of Diffractive Production Of D*±(2010) Mesons In Deep-Inelastic Scattering At Hera, S. Chekanov, D. Krakauer, S. Magill, B. Musgrave, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, A. Margotti, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli, A. Zichichi, G. Aghuzumtsyan, D. Bartsch, I. Brock Oct 2002

Measurement Of Diffractive Production Of D*±(2010) Mesons In Deep-Inelastic Scattering At Hera, S. Chekanov, D. Krakauer, S. Magill, B. Musgrave, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, A. Margotti, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli, A. Zichichi, G. Aghuzumtsyan, D. Bartsch, I. Brock

Faculty Publications

Diffractive production of D*±(2010) mesons in deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 44.3 pb-1. Diffractive charm production is identified by the presence of a large rapidity gap in the final state of events in which a D*±(2010) meson is reconstructed in the decay channel D*+ → (D0 → K-π+)πs+ (+ charge conjugate). Differential cross sections when compared with theoretical predictions indicate the importance of gluons in such diffractive interactions. © 2002 Elsevier Science B.V. All rights reserved.

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Seismic Experiments Target Earthquake-Prone Region In Romania, F Hauser, C Prodehl, M Landes, A Bala, V Raileanu, J Bribach, James H. Knapp, Camelia C. Diaconescu, C Dinu, V Mocanu, W Fielitz, S Harder, G. Randy Keller, E Hegedues, R A. Stephenson Oct 2002

Seismic Experiments Target Earthquake-Prone Region In Romania, F Hauser, C Prodehl, M Landes, A Bala, V Raileanu, J Bribach, James H. Knapp, Camelia C. Diaconescu, C Dinu, V Mocanu, W Fielitz, S Harder, G. Randy Keller, E Hegedues, R A. Stephenson

Faculty Publications

No abstract provided.

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Fluid Dynamics Of Flapping Aquatic Flight In The Bird Wrasse: Three-Dimensional Unsteady Computations With Fin Deformation, Ravi Ramamurti, William C. Sandberg, Rainald Lӧhner, Jeffrey A. Walker Phd, Mark W. Westneat Oct 2002

Fluid Dynamics Of Flapping Aquatic Flight In The Bird Wrasse: Three-Dimensional Unsteady Computations With Fin Deformation, Ravi Ramamurti, William C. Sandberg, Rainald Lӧhner, Jeffrey A. Walker Phd, Mark W. Westneat

Faculty Publications

Many fishes that swim with the paired pectoral fins use fin-stroke parameters that produce thrust force from lift in a mechanism of underwater flight. These locomotor mechanisms are of interest to behavioral biologists, biomechanics researchers and engineers. In the. present study, we performed the first three-dimensional unsteady computations of fish swimming with oscillating and deforming fins. The objective of these computations was to investigate the fluid dynamics of force production associated with the flapping aquatic flight of the bird wrasse Gomphosus varius. For this computational work, we used the geometry of the wrasse and its pectoral fin, and previously measured …

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Direct Estimation Of Aboveground Forest Productivity Through Hyperspectral Remote Sensing Of Canopy Nitrogen, Marie-Louise Smith, Scott V. Ollinger, Mary E. Martin, John D. Aber, Richard A. Hallett, Christine L. Goodale Oct 2002

Direct Estimation Of Aboveground Forest Productivity Through Hyperspectral Remote Sensing Of Canopy Nitrogen, Marie-Louise Smith, Scott V. Ollinger, Mary E. Martin, John D. Aber, Richard A. Hallett, Christine L. Goodale

Faculty Publications

The concentration of nitrogen in foliage has been related to rates of net photosynthesis across a wide range of plant species and functional groups and thus represents a simple and biologically meaningful link between terrestrial cycles of carbon and nitrogen. Although foliar N is used by ecosystem models to predict rates of leaf‐level photosynthesis, it has rarely been examined as a direct scalar to stand‐level carbon gain. Establishment of such relationships would greatly simplify the nature of forest C and N linkages, enhancing our ability to derive estimates of forest productivity at landscape to regional scales. Here, we report on …

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Triples Of Arrangements And Local Systems, Daniel C. Cohen Oct 2002

Triples Of Arrangements And Local Systems, Daniel C. Cohen

Faculty Publications

For a triple of complex hyperplane arrangements, there is a well-known long exact sequence relating the cohomology of the complements. We observe that this result extends to certain local coefficient systems, and use this extension to study the characteristic varieties of arrangements. We show that the first characteristic variety may contain components that are translated by characters of any order, thereby answering a question of A. Suciu.

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Performance Evaluation Of Path Searching Heuristics For Multicast Qos Routing, Daniel Zappala, Dayi Zhou Oct 2002

Performance Evaluation Of Path Searching Heuristics For Multicast Qos Routing, Daniel Zappala, Dayi Zhou

Faculty Publications

Quality of Service routing for multicast enables a group member to find and install a branch of the multicast tree that can meet its QoS constraints. The most promising protocols in this area use receiver-oriented path searching heuristics to find feasible routes. In this paper, we examine the performance of the path searching heuristics used by these protocols, to determine which techniques are the most effective. We find that several low-overhead path searching heuristics are effective, and that generic path searching can work as well as targeted, QoS-specific searching.

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Transaction Costs Relating To Acquisition Or Enhancement Of Intangible Property: A Populist, Political, But Practical Perspective, John W. Lee Oct 2002

Transaction Costs Relating To Acquisition Or Enhancement Of Intangible Property: A Populist, Political, But Practical Perspective, John W. Lee

Faculty Publications

No abstract provided.

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Compact Focusing Von Hamos Spectrometer For Quantitative X-Ray Spectroscopy, Larry V. Knight, A. P. Shevelko, Yu S. Kasyanov, O. F. Yakushev Oct 2002

Compact Focusing Von Hamos Spectrometer For Quantitative X-Ray Spectroscopy, Larry V. Knight, A. P. Shevelko, Yu S. Kasyanov, O. F. Yakushev

Faculty Publications

A compact focusing crystal spectrometer based on the von Hamos scheme is described. Cylindrically curved mica and graphite crystals with a radius of curvature of R = 20 mm are used in the spectrometer. A front illuminated charge-coupled device (CCD) linear array detector makes this spectrometer useful for real-time spectroscopy of laser-produced plasma x-ray sources within the wavelength range of lambda= 1.8-10 Angstroms. Calibration of crystals and the CCD linear array makes it possible to measure absolute photon fluxes. X-ray spectra in an absolute intensity scale were obtained from Mg, Ti, and Fe laser-produced plasmas, with a spectral resolution lambda/delta …

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Bluetooth: An Emerging Technology For Wireless Personal Area Networks, Eric S. Hall, Charles D. Knutson, David K. Vawdrey Oct 2002

Bluetooth: An Emerging Technology For Wireless Personal Area Networks, Eric S. Hall, Charles D. Knutson, David K. Vawdrey

Faculty Publications

Look under your desk or behind your computer. See that rat’s nest of wires and cables? Almost every cable or wire that tethers us to our devices (or our devices to one another) is unnecessary. Bluetooth wireless technology promises to reduce the cabling chaos that afflicts us all. Bluetooth is a recently developed technology that uses radio frequency (RF) transceivers to provide point-to-multipoint wireless connectivity within a personal space. Bluetooth was designed for both voice and data communication at low per-unit costs while consuming little power. To achieve the cost and power goals, Bluetooth limits connectivity to a sphere of …

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The Nature Of Interchain Excitations In Conjugated Polymers: Spatially-Varying Interfacial Solvatochromism Of Annealed Meh-Ppv Films Studied By Near-Field Scanning Optical Microscopy (Nsom), Richard D. Schaller, Lynn F. Lee, Justin C. Johnson, Louis H. Haber, Richard J. Saykally, John Vieceli, Ilan Benjamin, Thuc Quyen Nguyen, Benjamin J. Schwartz Sep 2002

The Nature Of Interchain Excitations In Conjugated Polymers: Spatially-Varying Interfacial Solvatochromism Of Annealed Meh-Ppv Films Studied By Near-Field Scanning Optical Microscopy (Nsom), Richard D. Schaller, Lynn F. Lee, Justin C. Johnson, Louis H. Haber, Richard J. Saykally, John Vieceli, Ilan Benjamin, Thuc Quyen Nguyen, Benjamin J. Schwartz

Faculty Publications

The nature of interchain excitations in conjugated polymers was discussed. The spatially-varying solvatochromism of annealed poly(2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylene vinylene) (MEH-PPV) films were studied by near-field scanning optical microscopy (NSOM). The solvatochromic spectral shifts of the interfacial luminescence were measured as a function of solvent polarity. The results were analyzed with an interfacial dielectric continuum model to determine the dipole moment of emissive excited states.

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