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Faculty Publications

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Articles 2371 - 2400 of 3797

Full-Text Articles in Physical Sciences and Mathematics

Data-Driven Programming And Behavior For Autonomous Virtual Characters, Jonathan Dinerstein, Parris K. Egbert, Michael A. Goodrich, Dan A. Ventura Jul 2008

Data-Driven Programming And Behavior For Autonomous Virtual Characters, Jonathan Dinerstein, Parris K. Egbert, Michael A. Goodrich, Dan A. Ventura

Faculty Publications

In the creation of autonomous virtual characters, two levels of autonomy are common. They are often called motion synthesis (low-level autonomy) and behavior synthesis (high-level autonomy), where an action (i.e. motion) achieves a short-term goal and a behavior is a sequence of actions that achieves a long-term goal. There exists a rich literature addressing many aspects of this general problem (and it is discussed in the full paper). In this paper we present a novel technique for behavior (high-level) autonomy and utilize existing motion synthesis techniques. Creating an autonomous virtual character with behavior synthesis abilities frequently includes three stages: forming …

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A High Resolution Neutrino Experiment In A Magnetic Field For Project-X At Fermilab, Sanjib R. Mishra, Roberto Petti, Carl Rosenfeld Jun 2008

A High Resolution Neutrino Experiment In A Magnetic Field For Project-X At Fermilab, Sanjib R. Mishra, Roberto Petti, Carl Rosenfeld

Faculty Publications

We propose a new high-resolution neutrino experiment within a dipole magnetic field, HiResMν. This experiment will run along with long-baseline neutrino oscillation experiments (LBLν) such as NOνA, a large-cavity detector at DUSEL, or a Liquid-Argon detector in the Medium-Energy (ME) configuration of the NuMI-beam. Assuming the 120 GeV Main Injector proton intensities we anticipate 140(50) million νμ (⊽μ) Charged-Current (CC) events in the fiducial volume, for 3(4)-year run with the ME (anti)neutrino beam. Alternatively, the same statistics could be collected in just 1(1.5) year with the High Energy (HE) beam configuration. …

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The Role Of Upstream Sequences In Selecting The Reading Frame On Tmrna, Allen R. Buskirk, Mickey R. Miller, David W. Healey, Jonathan D. Dewey, Stephen G. Robison Jun 2008

The Role Of Upstream Sequences In Selecting The Reading Frame On Tmrna, Allen R. Buskirk, Mickey R. Miller, David W. Healey, Jonathan D. Dewey, Stephen G. Robison

Faculty Publications

tmRNA acts first as a tRNA and then as an mRNA to rescue stalled ribosomes in eubacteria. Two unanswered questions about tmRNA function remain: how does tmRNA, lacking an anticodon, bypass the decoding machinery and enter the ribosome? Secondly, how does the ribosome choose the proper codon to resume translation on tmRNA? According to the -1 triplet hypothesis, the answer to both questions lies in the unique properties of the three nucleotides upstream of the first tmRNA codon. These nucleotides assume an A-form conformation that mimics the codon-anticodon interaction, leading to recognition by the decoding center and choice of the …

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Manipulating The Cavity Of A Porous Material Changes The Photoreactivity Of Included Guests, Mahender B. Dewal, Yuewen Xu, Jun Yang, Fiaz Mohammed, Mark D. Smith, Linda S. Shimizu Jun 2008

Manipulating The Cavity Of A Porous Material Changes The Photoreactivity Of Included Guests, Mahender B. Dewal, Yuewen Xu, Jun Yang, Fiaz Mohammed, Mark D. Smith, Linda S. Shimizu

Faculty Publications

Changing an ether to a ketone within the framework of a bis-urea macrocycle has little effect on the supramolecular assembly of this building block into porous crystals but introduces a triplet sensitizer into the framework that dramatically alters the photochemical reactions of included guests.

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Characterizing Subpixel Variability Of Low Resolution Radiometer Derived Soil Moisture Using High Resolution Radar Data, Ujjwal Narayan, Venkataraman Lakshmi Jun 2008

Characterizing Subpixel Variability Of Low Resolution Radiometer Derived Soil Moisture Using High Resolution Radar Data, Ujjwal Narayan, Venkataraman Lakshmi

Faculty Publications

Soil moisture estimates obtained using passive remote sensing from satellite platforms often suffer from the drawback of coarse spatial resolution. In this current work, low resolution soil moisture estimates from passive remote sensing are fused with high resolution radar backscatter data to produce soil moisture change estimates at the spatial resolution of radar. More specifically, soil moisture estimated from AMSR-E and TMI (separate cases) for a single 50 km × 50 km pixel has been fused with TRMM-PR backscatter data at 5 km resolution to produce soil moisture change estimates at 5 km resolution. A brief sensitivity analysis has been …

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Algorithm For Generating Derivative Structures, Gus L. W. Hart, Rodney W. Forcade Jun 2008

Algorithm For Generating Derivative Structures, Gus L. W. Hart, Rodney W. Forcade

Faculty Publications

We present an algorithm for generating all derivative superstructures--for arbitrary parent structures and for any number of atom types. This algorithm enumerates superlattices and atomic configurations in a geometry-independent way. The key concept is to use the quotient group associated with each superlattice to determine all unique atomic configurations. The run time of the algorithm scales linearly with the number of unique structures found.

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Link Quality Prediction For Wireless Devices With Multiple Radios, Qiuyi Duan, Charles D. Knutson, Lei Wang, Daniel Zappala Jun 2008

Link Quality Prediction For Wireless Devices With Multiple Radios, Qiuyi Duan, Charles D. Knutson, Lei Wang, Daniel Zappala

Faculty Publications

Communication between wireless devices ought to be as simple as possible; they should be able to seamlessly switch between different radios and network stacks on the fly in order to better serve the user. To make this a possibility, we consider the challenging problem of predicting link quality in a changing mobile environment. In this paper we present an algorithm that uses Weighted Least Squares Regression to predict whether a given link can meet application requirements in terms of throughput, delay, and jitter. We use a simulation study to demonstrate that our algorithm is able to predict link quality accurately …

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Predicting The Hydrogen Pressure To Achieve Ultralow Friction And Diamondlike Carbon Surfaces From First Principles, Haibo Guo, Yue Qi, Xiaodong Li Jun 2008

Predicting The Hydrogen Pressure To Achieve Ultralow Friction And Diamondlike Carbon Surfaces From First Principles, Haibo Guo, Yue Qi, Xiaodong Li

Faculty Publications

Hydrogen atmosphere can significantly change the tribological behavior at diamond and diamondlike carbon (DLC) surfaces and the friction-reducing effect depends on the partial pressure of hydrogen. We combined density functional theory modeling and thermodynamic quantities to predict the equilibrium partial pressures of hydrogen at temperature T, PH2 (T), for a fully atomic hydrogen passivated diamondsurface. Above the equilibrium PH2 (T), ultralow friction can be achieved at diamond and DLC surfaces. The calculation agrees well with friction tests at various testing conditions. We also show that PH2 (T) …

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Astrophysically Triggered Searches For Gravitational Waves: Status And Prospects, B. Abbott, R. Abbott, R. Adhikari, P. Ajith, B. Allen, G. Allen, R. Amin, S. B. Anderson, W. G. Anderson, M. A. Arain, M. Araya, H. Armandula, P. Armor, Y. Aso, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, M. A. Barton, M. Bastarrika, K. Bayer, J. Betzwieser, P. T. Beyersdorf, I. A. Bilenko, Tiffany Z. Summerscales Jun 2008

Astrophysically Triggered Searches For Gravitational Waves: Status And Prospects, B. Abbott, R. Abbott, R. Adhikari, P. Ajith, B. Allen, G. Allen, R. Amin, S. B. Anderson, W. G. Anderson, M. A. Arain, M. Araya, H. Armandula, P. Armor, Y. Aso, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, M. A. Barton, M. Bastarrika, K. Bayer, J. Betzwieser, P. T. Beyersdorf, I. A. Bilenko, Tiffany Z. Summerscales

Faculty Publications

In gravitational-wave detection, special emphasis is put onto searches that focus on cosmic events detected by other types of astrophysical observatories. The astrophysical triggers, e.g. from γ-ray and x-ray satellites, optical telescopes and neutrino observatories, provide a trigger time for analyzing gravitational-wave data coincident with the event. In certain cases the expected frequency range, source energetics, directional and progenitor information are also available. Beyond allowing the recognition of gravitational waveforms with amplitudes closer to the noise floor of the detector, these triggered searches should also lead to rich science results even before the onset of Advanced LIGO. In this paper …

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A Boundary Meshless Method Using Chebyshev Interpolation And Trigonometric Basis Function For Solving Heat Conduction Problems, S. Yu. Reutskiy, C.S. Chen, Haiyan Y. Tian Jun 2008

A Boundary Meshless Method Using Chebyshev Interpolation And Trigonometric Basis Function For Solving Heat Conduction Problems, S. Yu. Reutskiy, C.S. Chen, Haiyan Y. Tian

Faculty Publications

A boundary meshless method has been developed to solve the heat conduction equations through the use of a newly established two-stage approximation scheme and a trigonometric series expansion scheme to approximate the particular solution and fundamental solution, respectively. As a result, no fundamental solution is required and the closed form of approximate particular solution is easy to obtain. The effectiveness of the proposed computational scheme is demonstrated by several examples in 2D and 31). We also compare our proposed method with the finite-difference method and the other meshless method showed in Sarler and Vertnik (Comput. Math. Appl. 2006; 51:1269-1282). Excellent …

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Or Best Offer: A Privacy Policy Negotiation Protocol, Eric G. Mercer, Kent E. Seamons, Daniel D. Walker Jun 2008

Or Best Offer: A Privacy Policy Negotiation Protocol, Eric G. Mercer, Kent E. Seamons, Daniel D. Walker

Faculty Publications

Privacy policy languages, such as P3P, allow websites to publish their privacy practices and policies in machine readable form. Currently, software agents designed to protect users’ privacy follow a “take it or leave it” approach that is inflexible and gives the server ultimate control. Privacy policy negotiation is one approach to leveling the playing field by allowing a client to negotiate with a server to determine how that server collects and uses the client’s data. We present a privacy policy negotiation protocol, “Or Best Offer”, that includes a formal model for specifying privacy preferences and reasoning about privacy policies. The …

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Assessing The Costs Of Sampling Methods In Active Learning For Annotation, James Carroll, Robbie Haertel, Peter Mcclanahan, Eric K. Ringger, Kevin Seppi Jun 2008

Assessing The Costs Of Sampling Methods In Active Learning For Annotation, James Carroll, Robbie Haertel, Peter Mcclanahan, Eric K. Ringger, Kevin Seppi

Faculty Publications

Traditional Active Learning (AL) techniques assume that the annotation of each datum costs the same. This is not the case when annotating sequences; some sequences will take longer than others. We show that the AL technique which performs best depends on how cost is measured. Applying an hourly cost model based on the results of an annotation user study, we approximate the amount of time necessary to annotate a given sentence. This model allows us to evaluate the effectiveness of AL sampling methods in terms of time spent in annotation. We acheive a 77% reduction in hours from a random …

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Application And Evaluation Of Spatiotemporal Enhancement Of Live Aerial Video Using Temporally Local Mosaics, Dennis Eggett, Cameron Engh, Damon Gerhardt, Michael A. Goodrich, Bryan S. Morse, Nathan Rasmussen, Daniel Thornton Jun 2008

Application And Evaluation Of Spatiotemporal Enhancement Of Live Aerial Video Using Temporally Local Mosaics, Dennis Eggett, Cameron Engh, Damon Gerhardt, Michael A. Goodrich, Bryan S. Morse, Nathan Rasmussen, Daniel Thornton

Faculty Publications

Camera-equipped mini-UAVs are popular for many applications, including search and surveillance, but video from them is commonly plagued with distracting jittery motions and disorienting rotations that make it difficult for human viewers to detect objects of interest and infer spatial relationships. For time-critical search situations there are also inherent tradeoffs between detection and search speed. These problems make the use of dynamic mosaics to expand the spatiotemporal properties of the video appealing. However, for many applications it may not be necessary to maintain full mosaics of all of the video but to mosaic and retain only a number of recent …

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Energy Dependence Of The Charged Multiplicity In Deep Inelastic Scattering At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, M. Jechow, N. Pavel, P. Antonioli, G. Bari, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, F. Cindolo, M. Corradi, G. Iacobucci, A. Margotti, R. Nania, A. Polini, S. Antonelli, M. Basile, M. Bindi, L. Cifarelli, A. Contin, S. De Pasquale, G. Sartorelli, A. Zichichi, D. Bartsch Jun 2008

Energy Dependence Of The Charged Multiplicity In Deep Inelastic Scattering At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, M. Jechow, N. Pavel, P. Antonioli, G. Bari, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, F. Cindolo, M. Corradi, G. Iacobucci, A. Margotti, R. Nania, A. Polini, S. Antonelli, M. Basile, M. Bindi, L. Cifarelli, A. Contin, S. De Pasquale, G. Sartorelli, A. Zichichi, D. Bartsch

Faculty Publications

The charged multiplicity distributions and the mean charged multiplicity have been investigated in inclusive neutral current deep inelastic ep scattering with the ZEUS detector at HERA, using an integrated luminosity of 38.6 pb-1. The measurements were performed in the current region of the Breit frame, as well as in the current fragmentation region of the hadronic centre-of-mass frame. The KNO-scaling properties of the data were investigated and the energy dependence was studied using different energy scales. The data are compared to results obtained in e+e- collisions and to previous DIS measurements as well as to leading-logarithm parton-shower Monte Carlo predictions. …

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The Enigmatic Young Object: Walker 90/V590 Monocerotis, M. D. Joner, M. R. Perez, B. Mccollum, M. E. Van Dend Ancker May 2008

The Enigmatic Young Object: Walker 90/V590 Monocerotis, M. D. Joner, M. R. Perez, B. Mccollum, M. E. Van Dend Ancker

Faculty Publications

Aims. We assess the evolutionary status of the intriguing object Walker 90/V590 Mon, which is located about 20 arcmin northwest of the Cone Nebula near the center of the open cluster NGC 2264. This object, according to its most recent optical spectral type determination (B7), which we confirmed, is at least 3 mag too faint in V for the cluster distance, but it shows the classical signs of a young pre-main sequence object, such as highly variable H emission, Mg II emission, IR excess, UV continuum, and optical variability. Methods. We analyzed a collection of archival and original data on …

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A Joint Search For Gravitational Wave Bursts With Auriga And Ligo, L. Baggio, M. Bignotto, M. Bonaldi, M. Cerdonio, M. De Rosa, P. Falferi, S. Fattori, P. Fortini, G. Giusfredi, M. Inguscio, N. Liguori, S. Longo, F. Marin, R. Mezzena, A. Mion, A. Ortolan, S. Poggi, G. A. Prodi, V. Re, F. Salemi, G. Soranzo, L. Taffarello, G. Vedovato, A. Vinante, S. Vitale, J. P. Zendri, B. Abbott, R. Abbott, R. Adhikari, J. Agresti, P. Ajith, Tiffany Z. Summerscales May 2008

A Joint Search For Gravitational Wave Bursts With Auriga And Ligo, L. Baggio, M. Bignotto, M. Bonaldi, M. Cerdonio, M. De Rosa, P. Falferi, S. Fattori, P. Fortini, G. Giusfredi, M. Inguscio, N. Liguori, S. Longo, F. Marin, R. Mezzena, A. Mion, A. Ortolan, S. Poggi, G. A. Prodi, V. Re, F. Salemi, G. Soranzo, L. Taffarello, G. Vedovato, A. Vinante, S. Vitale, J. P. Zendri, B. Abbott, R. Abbott, R. Adhikari, J. Agresti, P. Ajith, Tiffany Z. Summerscales

Faculty Publications

The first simultaneous operation of the AURIGA detector and the LIGO observatory was an opportunity to explore real data, joint analysis methods between two very different types of gravitational wave detectors: resonant bars and interferometers. This paper describes a coincident gravitational wave burst search, where data from the LIGO interferometers are cross-correlated at the time of AURIGA candidate events to identify coincident transients. The analysis pipeline is tuned with two thresholds, on the signal-to-noise ratio of AURIGA candidate events and on the significance of the cross-correlation test in LIGO. The false alarm rate is estimated by introducing time shifts between …

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An Optimal-Order Error Estimate For A Family Of Ellam-Mfem Approximations To Porous Medium Flow, Hong Wang May 2008

An Optimal-Order Error Estimate For A Family Of Ellam-Mfem Approximations To Porous Medium Flow, Hong Wang

Faculty Publications

Mathematical models used to describe porous medium flow lead to coupled systems of time-dependent nonlinear partial differential equations, which present serious mathematical and numerical difficulties. Standard methods tend to generate numerical solutions with nonphysical oscillations or numerical dispersion along with spurious grid-orientation effect. The ELLAM-MFEM time-stepping procedure, in which an Eulerian–Lagrangian localized adjoint method (ELLAM) is used to solve the transport equation and a mixed finite element method (MFEM) is used for the pressure equation, simulates porous medium flow accurately even if large spatial grids and time steps are used. In this paper we prove an optimal-order error estimate for …

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Optical Phase Unwrapping In The Presence Of Branch Points, Todd M. Venema [*], Jason D. Schmidt May 2008

Optical Phase Unwrapping In The Presence Of Branch Points, Todd M. Venema [*], Jason D. Schmidt

Faculty Publications

Strong turbulence causes phase discontinuities known as branch points in an optical field. These discontinuities complicate the phase unwrapping necessary to apply phase corrections onto a deformable mirror in an adaptive optics (AO) system. This paper proposes a non-optimal but effective and implementable phase unwrapping method for optical fields containing branch points. This method first applies a least-squares (LS) unwrapper to the field which isolates and unwraps the LS component of the field. Four modulo-2π-equivalent non-LS components are created by subtracting the LS component from the original field and then restricting the result to differing ranges. 2π phase jumps known …

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On The Steering Of Sound Energy Through A Supercritical Plate By A Near-Field Transducer Array, Brian E. Anderson, Stephen A. Hambric, Jack W. Hughes May 2008

On The Steering Of Sound Energy Through A Supercritical Plate By A Near-Field Transducer Array, Brian E. Anderson, Stephen A. Hambric, Jack W. Hughes

Faculty Publications

The ability to direct sound energy through the flexural vibrations of a submerged plate at various angles of incidence using a near-field transducer array is investigated. An alumina bar is placed in front of a one-dimensional, eight-element transducer array, between the array and the water. Operating in a receive mode, data were taken as a function of angle of incidence and compared to data taken without the presence of the alumina bar. The array was also operated in transmit mode and results were compared to corresponding receive mode data, showing that reciprocity holds. Results show that in fact sound energy …

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Diffractive Photoproduction Of Dijets In Ep Collisions At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, M. Jechow, N. Pavel, A. G. Yagües Molina, S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, G. Sartorelli, A. Zichichi May 2008

Diffractive Photoproduction Of Dijets In Ep Collisions At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, M. Jechow, N. Pavel, A. G. Yagües Molina, S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, G. Sartorelli, A. Zichichi

Faculty Publications

Diffractive photoproduction of dijets was measured with the ZEUS detector at the ep collider HERA using an integrated luminosity of 77.2 pb-1. The measurements were made in the kinematic range Q2 < 1 GeV 2, 0.20

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Integrating Trust Into The Cybercraft Initiative Via The Trust Vectors Model, Michael Stevens, Paul D. Williams, Gilbert L. Peterson, Stuart H. Kurkowski May 2008

Integrating Trust Into The Cybercraft Initiative Via The Trust Vectors Model, Michael Stevens, Paul D. Williams, Gilbert L. Peterson, Stuart H. Kurkowski

Faculty Publications

This research supports the hypothesis that the Trust Vector model can be modified to fit the CyberCraft Initiative, and that there are limits to the utility of historical data. This research proposed some modifications and expansions to the Trust Model Vector, and identified areas for future research.

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Co2 Fixation Kinetics Of Halothiobacillus Neapolitanus Mutant Carboxysomes Lacking Carbonic Anhydrase Suggest The Shell Acts As A Diffusional Barrier For Co2, Zhicheng Dou, Sabine Heinhorst, Eric B. Williams, C. Daniel Murin, Jessup M. Shively, Gordon C. Cannon Apr 2008

Co2 Fixation Kinetics Of Halothiobacillus Neapolitanus Mutant Carboxysomes Lacking Carbonic Anhydrase Suggest The Shell Acts As A Diffusional Barrier For Co2, Zhicheng Dou, Sabine Heinhorst, Eric B. Williams, C. Daniel Murin, Jessup M. Shively, Gordon C. Cannon

Faculty Publications

The widely accepted models for the role of carboxysomes in the carbon-concentrating mechanism of autotrophic bacteria predict the carboxysomal carbonic anhydrase to be a crucial component. The enzyme is thought to dehydrate abundant cytosolic bicarbonate and provide ribulose 1.5-bisphosphate carboxylase/oxygenase (RubisCO) sequestered within the carboxysome with sufficiently high concentrations of its substrate, CO2, to permit its efficient fixation onto ribulose 1,5-bisphosphate. In this study, structure and function of carboxysomes purified from wild type Halothiobacillus neapolitanus and from a high CO2-requiring mutant that is devoid of carboxysomal carbonic anhydrase were compared. The kinetic constants for the carbon …

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Metallicity And Effective Temperature Of The Secondary Or Rs Ophicuhi, R. L. Pearson Iii, Ya. V. Pavlenko, A. Evans, T. Kerr, L. Yakovina, C. E. Woodward, D. Lynch, R. Rudy, R. W. Russell Apr 2008

Metallicity And Effective Temperature Of The Secondary Or Rs Ophicuhi, R. L. Pearson Iii, Ya. V. Pavlenko, A. Evans, T. Kerr, L. Yakovina, C. E. Woodward, D. Lynch, R. Rudy, R. W. Russell

Faculty Publications

Context. The recurrent nova RS Ophiuchi undergoes nova eruptions every 10-20 years as a result of thermonuclear runaway on the surface of a white dwarf close to the Chandrasekhar limit. Both the progress of the eruption and its aftermath depend on the (poorly known) composition of the red giant in the RS Oph system. Aims. Our aim is to understand better the effect of the giant secondary on the recurrent nova eruption. Methods. Synthetic spectra were computed for a grid of M-giant model atmospheres having a range of effective temperatures 3200 < Teff < 4400 K, gravities 0 < log g < 1 and abundances -4 < [Fe/H] < 0.5, and fit to infrared spectra of RS Oph as it returned to quiescence after its 2006 eruption. We have modelled the infrared spectrum in the range 1.4-2.5µm to determine metallicity and effective temperature of the red giant. Results. We find Teff= 4100 ±100 K, log g = 0.0 ±0.5, [Fe/H] = 0.0 ±0.5, [C/H] = -0.8 ±0.2, [N/H] = +0.6 ±0.3 in the atmosphere of the secondary, and demonstrate that inclusion of some dust "veiling" in the spectra cannot improve our fits.

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Asymmetry Of Recoil Protons In Neutron Β Decay, Vladimir Gudkov Apr 2008

Asymmetry Of Recoil Protons In Neutron Β Decay, Vladimir Gudkov

Faculty Publications

A complete analysis of proton recoil asymmetry in neutron decay in the first order of radiative and recoil corrections is presented. The possible contributions from new physics are calculated in terms of low energy coupling constants, and the sensitivity of the measured asymmetry to models beyond the Standard Model are discussed.

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W(H)Ither Fossils? Studying Morphological Character Evolution In The Age Of Molecular Sequences, Elizabeth J. Hermsen, Jonathan R. Hendricks Apr 2008

W(H)Ither Fossils? Studying Morphological Character Evolution In The Age Of Molecular Sequences, Elizabeth J. Hermsen, Jonathan R. Hendricks

Faculty Publications

A major challenge in the post-genomics era will be to integrate molecular sequence data from extant organisms with morphological data from fossil and extant taxa into a single, coherent picture of phylogenetic relationships; only then will these phylogenetic hypotheses be effectively applied to the study of morphological character evolution. At least two analytical approaches to solving this problem have been utilized: (1) simultaneous analysis of molecular sequence and morphological data with fossil taxa included as terminals in the analysis, and (2) the molecular scaffold approach, in which morphological data are analyzed over a molecular backbone (with constraints that force extant …

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Hypogenic Speleogenesis Within Seven Rivers Evaporites: Coffee Cave, Eddy County, New Mexico, Kevin W. Stafford, Lewis Land, Alexander Klimchouk Apr 2008

Hypogenic Speleogenesis Within Seven Rivers Evaporites: Coffee Cave, Eddy County, New Mexico, Kevin W. Stafford, Lewis Land, Alexander Klimchouk

Faculty Publications

Coffee Cave, located in the lower Pecos region of southeastern New Mexico, illustrates processes of hypogenic speleogenesis in the middle Permian Seven Rivers Formation. Coffee Cave is a rectilinear gypsum maze cave with at least four stratigraphically-distinct horizons of development. Morphological features throughout the cave provide unequivocal evidence of hypogenic ascending speleogenesis in a confined aquifer system driven by mixed (forced and free) convection. Morphologic features in individual cave levels include a complete suite that defines original rising flow paths, ranging from inlets for hypogenic fluids (feeders) through transitional forms (rising wall channels) to ceiling half-tube flow features and fluid …

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Skill Evaluation In Women's Volleyball, Lindsay W. Florence, Gilbert W. Fellingham, Pat R. Vehrs, Nina P. Mortensen Apr 2008

Skill Evaluation In Women's Volleyball, Lindsay W. Florence, Gilbert W. Fellingham, Pat R. Vehrs, Nina P. Mortensen

Faculty Publications

The Brigham Young University Women's Volleyball Team recorded and rated all skills (pass, set, attack, etc.) and recorded rally outcomes (point for BYU, rally continues, point for opponent) for the entire 2006 home volleyball season. Only sequences of events occurring on BYU's side of the net were considered. Events followed one of these general patterns: serve-outcome, pass-set-attack-outcome, or block-dig-set-attack-outcome. These sequences of events were assumed to be first-order Markov chains where the quality of each contact depended only on the quality of the previous contact but not explicitly on contacts further removed in the sequence. We represented these sequences in …

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Three- And Four-Jet Final States In Photoproduction At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, M. Jechow, N. Pavel, A. G. Yagües Molina, S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, G. Sartorelli, A. Zichichi Mar 2008

Three- And Four-Jet Final States In Photoproduction At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, M. Jechow, N. Pavel, A. G. Yagües Molina, S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, G. Sartorelli, A. Zichichi

Faculty Publications

Three- and four-jet final states have been measured in photoproduction at HERA using the ZEUS detector with an integrated luminosity of 121 pb -1. The results are presented for jets with transverse energy E Tjet > 6 GeV and pseudorapidity | η jet | < 2.4, in the kinematic region given by the virtuality of the photon Q 2 < 1 GeV 2 and the inelasticity 0.2 ≤ y ≤ 0.85 and in two mass regions defined as 25 ≤ M n j < 50 GeV and M n j ≥ 50 GeV, where M n j is the invariant mass of the n-jet system. The four-jet photoproduction cross section has been measured for the first time and represents the highest-order process studied at HERA. Both the three- and four-jet cross sections have been compared with leading-logarithmic parton-shower Monte Carlo models, with and without multi-parton interactions. The three-jet cross sections have been compared to an O (α α s2) perturbative QCD calculation. © 2007 Elsevier B.V. All rights reserved.

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Comment On “Contact Conditions For The Charge In The Theory Of The Electrical Double Layer”, Douglas Henderson, L. B. Bhuiyan Mar 2008

Comment On “Contact Conditions For The Charge In The Theory Of The Electrical Double Layer”, Douglas Henderson, L. B. Bhuiyan

Faculty Publications

Exact results in any field, including statistical mechanics, are both aesthetically pleasing and very valuable in assessing theoretical approximations.

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Search For Gravitational Waves Associated With 39 Gamma-Ray Bursts Using Data From The Second, Third, And Fourth Ligo Runs, B. Abbott, R. Abbott, R. Adhikari, J. Agresti, P. Ajith, B. Allen, R. Amin, S. B. Anderson, W. G. Anderson, M. Arain, M. Araya, H. Armandula, M. Ashley, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, M. A. Barton, K. Bayer, K. Belczynski, S. J. Berukoff, J. Betzwieser, P. T. Beyersdorf, B. Bhawal, Tiffany Z. Summerscales Mar 2008

Search For Gravitational Waves Associated With 39 Gamma-Ray Bursts Using Data From The Second, Third, And Fourth Ligo Runs, B. Abbott, R. Abbott, R. Adhikari, J. Agresti, P. Ajith, B. Allen, R. Amin, S. B. Anderson, W. G. Anderson, M. Arain, M. Araya, H. Armandula, M. Ashley, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, M. A. Barton, K. Bayer, K. Belczynski, S. J. Berukoff, J. Betzwieser, P. T. Beyersdorf, B. Bhawal, Tiffany Z. Summerscales

Faculty Publications

We present the results of a search for short-duration gravitational-wave bursts associated with 39 gamma-ray bursts (GRBs) detected by gamma-ray satellite experiments during LIGO's S2, S3, and S4 science runs. The search involves calculating the crosscorrelation between two interferometer data streams surrounding the GRB trigger time. We search for associated gravitational radiation from single GRBs, and also apply statistical tests to search for a gravitational-wave signature associated with the whole sample. For the sample examined, we find no evidence for the association of gravitational radiation with GRBs, either on a single-GRB basis or on a statistical basis. Simulating gravitational-wave bursts …

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