Physical Sciences and Mathematics Commons^™

Smith On Krauss, 'The Physics Of Star Trek', Anne Collins Smith

Faculty Publications

Review of Lawrence M. Krauss.The Physics of Star Trek. New York: Basic Books, 1995. xvi + 188 pp. $20.00(cloth), ISBN 978-0-465-00559-8.

Reviewed by Anne Collins Smith (Austin Community College) Published on H-PCAACA (May, 1996)

A Brief Introduction To Formal Methods, Paul E. Black, Kelly M. Hall, Michael D. Jones, Trent N. Larson, Phillip J. Windley

Faculty Publications

As hardware designs grow in size and complexity, current design methods are proving less adequate. Current methods for specification, design, and test are typically empirical or informal, that is, they are based on experience and argument. Formal methods are solidly based on mathematical logic systems and precise rules of inference. Formal methods offer a discipline which complements current methods so designers can successfully meet the demand for high performance systems. Formal methods covers a broad and diverse set of techniques aimed at improving computer correctness. This paper explains the role of specifications and implementation models in formal methods, and different …

Simulations Of Electrostatic Modes Of Non-Neutral Plasmas With Small Aspect Ratio In A Penning Trap, Grant W. Mason, Ross L. Spencer, Jonathan A. Bennett

Faculty Publications

The dependence on induced charge, experimental geometry, and temperature of electrostatic modes in very low aspect ratio non-neutral plasmas in a Penning trap is considered. The modes are of interest as non-destructive diagnostics of the shape of the plasmas. These investigations include equilibrium calculations of plasma shapes and profiles at finite temperature and particle-in-cell simulations of axisymmetric modes. The results of the simulations are compared to the zero-temperature theory by Dubin [Phys. Rev. Lett. 66, 2076 (1991)] taken to first-order in the aspect ratio and to experimental measurements by Weimer et al. [Phys. Rev. A 49, 3842 (1994)]. In general, …

Error Correction Via A Post-Processor For Continuous Speech Recognition, Eric K. Ringger, James F. Allen

Faculty Publications

This paper presents a new technique for overcoming several types of speech recognition errors by post-processing the output of a continuous speech recognizer. The post-processor output contains fewer errors, thereby making interpretation by higher-level modules, such as a parser, in a speech understanding system more reliable. The primary advantage to the post-processing approach over existing approaches for overcoming SR errors lies in its abilityto introduce options that are not available in the SR module’s output. This work provides evidence for the claim that a modern continuous speech recognizer can be used successfully in “black-box” fashion for robustly interpreting spontaneous utterances …

Changing Source Characteristics During Multifragment Decay, T. M. Hamilton, E. Cornell, D. Fox, Y. Lou, R. T. De Souza, M. J. Huang, W. C. Hsi, C. Schwarz, C. Williams, D. R. Bowman, J. Dinius, C. K. Gelbke, T. Glasmacher, D. O. Handzy, M. A. Lisa, W. G. Lynch, Graham F. Peaslee, L. Phair, M. B. Tsang, G. Vanburen, R. J. Charity, L. G. Sobotka, A. A. Sonzogni, D. Prindle

Faculty Publications

The spatial-temporal extent of the emitting system for central collisions in Kr84 + Au197 at E/A = 35, 55, and 70 MeV is probed using fragment-fragment velocity correlation functions. Selection on fragment pairs of high velocity yields a stronger fragment-fragment Coulomb interaction than for inclusive fragment pairs. This result is consistent with fragment emission from a source of decreased spatial-temporal extent. The universality of this association and the effect of different selection criteria are explored. The sensitivity of the spatial-temporal extent deduced by the correlation function technique to measurement uncertainties, assumed source characteristics, and rotational effects is assessed.

The Advanced Glycation End Product, NE-(Carboxymethyl)Lysine, Is A Product Of Both Lipid Peroxidation And Glycoxidation Reactions, Min-Xin Fu, Jesus R. Requena, Alicia J. Jenkins, Timothy J. Lyons, John W. Baynes, Suzanne R. Thorpe

Faculty Publications

Nepsilon-(Carboxymethyl)lysine (CML) is an advanced glycation end product formed on protein by combined nonenzymatic glycation and oxidation (glycoxidation) reactions. We now report that CML is also formed during metal-catalyzed oxidation of polyunsaturated fatty acids in the presence of protein. During copper-catalyzed oxidation in vitro, the CML content of low density lipoprotein increased in concert with conjugated dienes but was independent of the presence of the Amadori compound, fructoselysine, on the protein. CML was also formed in a time-dependent manner in RNase incubated under aerobic conditions in phosphate buffer containing arachidonate or linoleate; only trace amounts of CML were formed from …

Circumstantial Evidence For A Critical Behavior In Peripheral Au+Au Collisions At 35 Mev/Nucleon, P. F. Mastinu, M. Belkacem, M. D'Agostino, M. Bruno, P. M. Milazzo, G. Vannini, D. R. Bowman, N. Colonna, J. D. Dinius, A. Ferrero, M. L. Fiandri, C. K. Gelbke, T. Glasmacher, F. Gramegna, D. O. Handzy, D. Horn, W. C. Hsi, M. Huang, I. Iori, G. J. Kunde, M. A. Lisa, W. G. Lynch, G. V. Margagliotti, C. P. Montoya, A. Moroni, Graham F. Peaslee, F. Petruzzelli, R. Rui, C. Schwarz, M. B. Tsang, C. Williams, V. Latora, A. Bonasera

Faculty Publications

The fragmentation resulting from peripheral Au+Au collisions at an incident energy of E=35MeV/nucleon is investigated. A power-law charge distribution, A−τ with τ≈2.2, and an intermittency signal are observed for events selected in the region of the Campi scatter plot where “critical” behavior is expected.

Compressing Semi-Structured Text Using Hierarchical Phrase Identifications, Dan R. Olsen Jr., Craig G. Nevill-Manning, Ian H. Witten

Faculty Publications

The structure of this paper is as follows. We begin by identifying some characteristics of semi-structured text that have special relevance to data compression. We then give a brief account of a particular large textual database, and describe a compression scheme that exploits its structure. In addition to providing compression, the system gives some insight into the structure of the database. Finally we show how the hierarchical grammar can be generalized, first manually and then automatically, to yield further improvements in compression performance.

Squeeze-Out Of Nuclear Matter In Au+Au Collisions, M. B. Tsang, P. Danielewicz, W. C. Hsi, M. Huang, W. G. Lynch, D. R. Bowman, C. K. Gelbke, M. A. Lisa, Graham F. Peaslee, R. J. Charity, L. G. Sobotka, M. L. Begemann-Blaich, F. Cosmo, A. Ferrero, J. Hubele, G. Imme, I. Iori, J. Kempter, G. J. Kunde, W. D. Kunze, V. Lindenstruth, U. Lynen, M. Mang, A. Moroni, W. F.J. Müller, M. Neumann, B. Ocker, C. A. Ogilive, J. Pochodzalla, G. Raciti, F. Rosenberger, T. Rubehn, H. Sann, R. Scardaoni, A. Schüttauf, C. Schwarz, W. Seidel, V. Serfling

Faculty Publications

Emission of charged particles from a compressed reaction zone is studied for Au197+197Au collisions at E/A=100, 250, and 400 MeV. Using a modified coalescence invariant weighting, squeeze-out ratios are determined and compared to predictions of cascade and BUU transport-model calculations.

Dynamics And Conformation Of Polymer Chains In A Porous Medium, Grace M. Foo, R.B. Pandey, D. Stauffer

Faculty Publications

No abstract provided.

Squeeze-Out Of Nuclear Matter In Au + Au Collisions, M. B. Tsang, P. Danielewicz, W. C. Hsi, M. Huang, W. G. Lynch, D. R. Bowman, C. K. Gelbke, M. A. Lisa, Graham F. Peaslee, R. J. Charity, L. G. Sobotka, M. L. Begemann-Blaich, F. Cosmo, A. Ferrero, J. Hubele, G. Imme, I. Iori, J. Kempter, P. Kruetz, G. J. Kunde, W. D. Kunze, V. Lindenstruth, U. Lynen, M. Mang, A. Moroni, W. F.J. Müller, M. Neumann, B. Ocker, C. A. Ogilvie, J. Pochodzalla, G. Raciti, F. Rosenberger, T. Rubehn, H. Sann, R. Scardaoni, A. Schüttauf, C. Schwarz, W. Seidel

Faculty Publications

Emission of charged particles from a compressed reaction zone is studied for Au197+197Au collisions at E/A=100, 250, and 400 MeV. Using a modified coalescence invariant weighting, squeeze-out ratios are determined and compared to predictions of cascade and BUU transport-model calculations.

Statistical Multifragmentation In Central Au+Au Collisions At 35 Mev/U, M. D'Agostino, A. S. Botvina, P. M. Milazzo, M. Bruno, G. J. Kunde, D. R. Bowman, L. Celano, N. Colonna, J. D. Dinius, A. Ferrero, M. L. Fiandri, C. K. Gelbke, T. Glasmacher, F. Gramegna, D. O. Handzy, D. Horn, W. C. Hsi, M. Huang, I. Iori, M. A. Lisa, W. G. Lynch, L. Manduci, G. V. Margagliotti, P. F. Mastinu, I. N. Mishustin, C. P. Montoya, A. Moroni, Graham F. Peaslee, F. Petruzzelli, L. Phair, R. Rui, C. Schwarz, M. B. Tsang, G. Vannini, C. Williams

Faculty Publications

Multifragment disintegrations, measured for central Au + Au collisions at , are analyzed with the Statistical Multifragmentation Model. Charge distributions, mean fragment energies, and two-fragment correlation functions are well reproduced by the statistical breakup of a large, diluted and thermalized system slightly above the multifragmentation threshold.

Rapidity Gaps Between Jets In Photoproduction At Hera, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, H. Zhang, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, R. Bruni, G. Cara Romeo, G. Castellini, M. Chiarini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, R. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, Margarita C. K. Mattingly

Faculty Publications

Photoproduction events which have two or more jets have been studied in the Wγp range 135 GeV < Wγp < 280 GeV with the ZEUS detector at HERA. A class of events is observed with little hadronic activity between the jets. The jets are separated by pseudorapidity intervals (Δη) of up to four units and have transverse energies greater than 6 GeV. A gap is defined as the absence between the jets of particles with transverse energy greater than 300 MeV. The fraction of events containing a gap is measured as a function of Δη. It decreases exponentially as expected for processes in which colour is exchanged between the jets, up to a value of Δη ∼ 3, then reaches a constant value of about 0.1. The excess above the exponential fall-off can be interpreted as evidence for hard diffractive scattering via a strongly interacting colour singlet object.

Multifragment Production In Au+Au At 35 Mev/U, M. D'Agostino, P. F. Mastinu, P. M. Milazzo, M. Bruno, D. R. Bowman, P. Buttazzo, L. Celano, N. Colonna, J. D. Dinius, A. Ferrero, M. L. Fiandri, C. K. Gelbke, T. Glasmacher, F. Gramegna, D. O. Handzy, D. Horn, W. C. Hsi, M. Huang, I. Iori, G. J. Kunde, M. A. Lisa, W. G. Lynch, L. Manduci, G. V. Margagliotti, C. P. Montoya, A. Moroni, Graham F. Peaslee, F. Petruzzelli, L. Phair, R. Rui, C. Schwarz, M. B. Tsang, G. Vannini, C. Williams

Faculty Publications

Multifragment disintegration has been measured with a high efficiency detection system for the reaction Au + Au at E/A = 35 MeV. From the event shape analysis and the comparison with the predictions of a many-body trajectories calculation the data, for central collisions, are compatible with a fast emission from a unique fragment source.

A Note On Generators Of Least Degree In Gorenstein Ideals, Matthew Miller, Rafael H. Villarreal

Faculty Publications

No abstract provided.

A Simple Model For Nonequilibrium Fluctuations In A Fluid, Alejandro Garcia, F. Baras, M. Malek Mansour

Faculty Publications

Presents a train model that shows the long-range spatial correlations of fluctuations in nonequilibrium fluid systems. Illustration of model through analysis of flat-car trains running on parallel tracks; Simulation of train model in computers; Theoretical analysis for fluctuations in the train model; Relationship between train model and the fluctuating hydrodynamic theory of fluids.

Seismogeological Features Of The Crust In Romania, V Mocanu, C Dinu, F Radulescu, M Diaconescu, Camelia C. Diaconescu, A Pompilian

Faculty Publications

The Romanian area consists of old consolidated units of pre-Alpine age (the Moesian, Moldavian and Scythian platforms) and Alpine orogenic units (the Carpathian arc and North-Dobrudjan orogen). General seismogeological peculiarities of the pre-Alpine tectonic units are presented, as well as some structural characteristics of the Transylvanian Basin and the Pannonian Depression. Both shallow and deep seismic reflection/refraction data as well as log information and some potential field data were used for the investigation of the crustal structure. The varibility in the seismogeological pattern and crustal thickness shown by the different tectonic units is due to the differences in structure and …

Branching Fractions And Oscillator Strengths For Fe Ii Transitions From The 3d6(5D)4p Subconfiguration, Scott D. Bergeson, K. L. Mullman, M. E. Wickliffe, J. E. Lawler

Faculty Publications

New experimental branching fractions and transition probabilities are reported for 56 transitions in Fe II. The branching fractions are measured with a Fourier transform spectrometer and also with a high-resolution grating spectrometer on a n optically thin hollow cathode discharge. Highly accurate experimental radiative lifetimes from the recent literature provide the normalization required to convert our branching fractions into absolute transition probabilities. Results are compared with experimental and theoretical values in the literature. Our new transition probabilities will establish the absolute scale for relative absorption oscillator strengths of vacuum ultraviolet lines measured using a new high-sensitivity absorption experiment at the …

High-Sensitivity Absorption Spectroscopy In Fe Ii, Scott D. Bergeson, K. L. Mullman, J. E. Lawler

Faculty Publications

We report the first measurements of UV oscillator strengths (ƒ-values) in Fe II from a high-sensitivity absorption experiment developed at the University of Wisconsin. The accuracy of our measurements is demonstrated by our reproducing well-known ƒ-value ratios in Fe I and Fe II. The first laboratory ƒ-value measurement of the 160.845 nm transition in Fe II is presented and compared to values in the literature. While this paper focuses on Fe II, the high-sensitivity absorption method that we have developed is applicable to essentially every element in the periodic table, for both neutral and ionized species, over a broad range …

Model Equations From Gyrokinetic Theory For A Non-Neutral Plasma To Include Temperature Effects And Applications To A Plasma Of Infinite Length, S. Neil Rasband

Faculty Publications

Gyrokinetic equations are derived for applications to non-neutral plasmas in constant, straight magnetic fields wherein E X B drift velocities are of the same order as thermal velocities. The ratio of the E X B rotation frequency to the cyclotron frequency and the ratio of the gyroradius to a plasma scale length are assumed to be of order epsilon and terms are retained in the gyrokinetic expansion to second order to include finite-Larmor-radius (FLR) effects. A mode equation is obtained for a non-neutral plasma in the infinite-length approximation. The singularities of this equation are compared and contrasted with the familiar …

A New High Pressure Sapphire Nuclear Magnetic Resonance Cell, Shi Bai, Craig M. Taylor, Charles L. Mayne, Ronald J. Pugmire, David M. Grant

Faculty Publications

A new version of a single-crystal sapphire high pressure nuclear magnetic resonance (NMR) cell is described that is capable of controlling the sample pressure independent of the temperature. A movable piston inside the cell adjusts and controls the sample pressure from ambient conditions to 200 atm within plus or minus 0.3 atm. The linewidth at half-height for a 13C spectrum of carbon dioxide at 15degrees C and 57.8 atm is found to be 0.5 Hz. The carbon dioxide gas/liquid phase transition is clearly observed by measuring 13C chemical shifts as the sample pressure approaches equilibrium. The time required for this …

Paracompact Subspaces In The Box Product Topology, Peter Nyikos, Leszek Piatkiwicz

Faculty Publications

No abstract provided.

Organic Matter Accumulation, Sulfate Reduction, And Methanogenesis In Pliocene–Pleistocene Turbidites On The Iberia Abyssal Plain, P. A. Meyers, Timothy J. Shaw

Faculty Publications

No abstract provided.

The Implications Of Turbidite-Driven Redox Changes In Sediments Of The Iberia Abyssal Plain, Timothy J. Shaw, P. A. Meyers

Faculty Publications

No abstract provided.

Galvanostatic Pulse And Pulse Reverse Plating Of Zinc-Nickel Alloys From Sulfate Electrolytes On A Rotating Disc Electrode, Branko N Popov, M. Ramasubramanian, S. N. Popova, Ralph E. White, K-M. Yin

Faculty Publications

Galvanostatic pulse and pulse reverse techniques have been used to study the plating of zinc–nickel alloys in the presence of nonyl phenyl polyethylene oxide. The effects of average current density, rotation speed of disc electrode and the presence of nonyl phenyl polyethylene oxide in the electrolyte on deposition of zinc–nickel alloys were evaluated. Zinc–nickel plating bath solution chemistry was studied by determining the equilibrium concentrations at various pH levels. It was found that the alloy composition was determined by solution equilibria, mass transfer of the electroactive species within the diffusion layer and by the surface coverage of nonyl phenyl polyethylene …

Measurement Of The F2 Structure Function In Deep Inelastic E+P Scattering Using 1994 Data From The Zeus Detector At Hera, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. R. Okrasinski, J. Repond, R. Stanek, R. L. Talaga, H. Zhang, Margarita C. K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi

Faculty Publications

We present measurements of the structure function F2 in e+p scattering at HERA in the range 3.5 GeV2 < Q2 < 5000 GeV2. A new reconstruction method has allowed a significant improvement in the resolution of the kinematic variables and an extension of the kinematic region covered by the experiment. At Q2 < 35 GeV2 the range in x now spans 6.3 · 10-5 < x < 0.08 providing overlap with measurements from fixed target experiments. At values of Q2 above 1000 GeV2 the x range extends to 0.5. Systematic errors below 5% have been achieved for most of the kinematic region. The structure function rises as x decreases; the rise becomes more pronounced as Q2 increases. The behaviour of the structure function data is well described by next-to-leading order perturbative QCD as implemented in the DGLAP evolution equations. © Springer-Verlag 1996.

Measurement Of Elastic Ω Photoproduction At Hera, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. R. Okrasiński, J. Repond, R. Stanek, R. L. Talaga, H. Zhang, Margarita C. K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi

Faculty Publications

No abstract provided.

Measurement Of The Diffractive Cross Section In Deep Inelastic Scattering, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. R. Okrasinski, J. Repond, R. Stanek, R. L. Talaga, H. Zhang, Margarita C. K. Mattingly, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam

Faculty Publications

© Springer-Verlag 1996. Diffractive scattering of γ∗p → X + N, where N is either a proton or a nucleonic system with MN < 4 GeV has been measured in deep inelastic scattering (DIS) at HERA. The cross section was determined by a novel method as a function of the γ∗p c.m. energy W between 60 and 245 GeV and of the mass MX of the system X up to 15 GeV at average Q2 values of 14 and 31 GeV2. The diffractive cross section dσdi f f /dMX is, within errors, found to rise linearly with W. Parameterizing the W dependence by the form dσdi f f /dMX ∞ (W2)(2αIP - 2) the DIS data yield for the pomeron trajectory αIP = 1.23±0.02(stat)±0.04(syst) averaged over t in the measured kinematic range assuming the longitudinal photon contribution to be zero. This value for the pomeron trajectory is substantially larger than αIP extracted from soft interactions. The value of αIP measured in this analysis suggests that a substantial part of the diffractive DIS cross section originates from processes which can be described by perturbative QCD. From the measured diffractive cross sections the diffractive structure function of the proton F2D(3) (β,Q2, xIP) has been determined, where β is the momentum fraction of the struck quark in the pomeron. The form F2D(3) = constant·(1/xIP)a gives a good fit to the data in all β and Q2 intervals with a = 1.46 ± 0.04(stat) ± 0.08(syst).

Reducibility And A New Entropic Term In Multifragment Charge Distribution, A. Ferrero, I. Iori, A. Moroni, F. Petruzelli, R. Scardaoni, L. G. Moretto, D. R. Bowman, M. Bruno, P. Buttazzo, L. Celano, N. Colonna, M. D'Agostino, J. D. Dinius, M. L. Fiandri, E. Fuschini, C. K. Gelbke, T. Glasmacher, F. Gramegna, D. O. Handzy, D. Horn, W. C. Hsi, M. Huang, G. J. Kunde, M. A. Lisa, W. G. Lynch, P. F. Mastinu, P. M. Milazzo, G. V. Margagliotti, C. P. Montoya, Graham F. Peaslee, L. Phair, R. Rui, C. Schwarz, M. B. Tsang, G. Vannini, C. Williams

Faculty Publications

The charge distributions and their dependence on fragment multiplicity have been studied for the multifragmentation of 30 MeV/nucleon Xe+Au, Cu. For both targets, the charge distributions are approximately independent of the fragment multiplicity n. However, a residual systematic dependence on n is detectable at the largest values of the total charge multiplicity Nc. Such n dependence obeys a simple scaling law and suggests the presence of an entropic term possibly related to the mechanism of multifragmentation. Thermal scaling between the different bins of Nc seems to occur.

Evaporation Residue, Fission Cross Sections, And Linear Momentum Transfer For 14n Induced Reactions From 35a To 155a Mev, A. A. Sonzogni, A. Elmaani, C. Hyde-Wright, W. Jiang, D. Prindle, R. Vandenbosch, J. Dinius, G. Cron, D. Bowman, C. K. Gelbke, W. Hsi, G. Lynch, C. Montoya, Graham F. Peaslee, C. Schwarz, M. B. Tsang, C. Williams, R. De Souza, D. Fox, T. Moore

Faculty Publications

Differential cross sections for evaporation residues and fission fragments for 35A, 100A, 130A and 155A MeV N14 on targets ranging from Sm154 to Au197 have been measured. The angle-integrated cross sections are larger than what might be expected. The fission fragment-fission fragment folding angle correlations for 35A, 100A MeV N14 and 25AMeV O16 on similar targets were also measured. The average linear momentum transfer has been deduced from both the fission angle correlation and from the fore-aft asymmetry of the fission angular distributions in the laboratory system. The data are all consistent with a picture where pre-equilibrium particle emission removes …