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Full-Text Articles in Physical Sciences and Mathematics

Sixth U.S.-Japan Seminar On Polymer Synthesis: Macromolecular Design For Advanced Materials, Otto Vogl, Shiro Kobayashi Dec 1994

Sixth U.S.-Japan Seminar On Polymer Synthesis: Macromolecular Design For Advanced Materials, Otto Vogl, Shiro Kobayashi

Emeritus Faculty Author Gallery

No abstract provided.


64. Tibor Kelen, Otto Vogl Dec 1994

64. Tibor Kelen, Otto Vogl

Emeritus Faculty Author Gallery

No abstract provided.


Polymer Institute Slovak Academy Of Sciences Bratislava, Slovakia, Otto Vogl Dec 1994

Polymer Institute Slovak Academy Of Sciences Bratislava, Slovakia, Otto Vogl

Emeritus Faculty Author Gallery

No abstract provided.


Third Pacific Polymer Conference. Gold Coast - Australia, Otto Vogl, Graeme A. George Nov 1994

Third Pacific Polymer Conference. Gold Coast - Australia, Otto Vogl, Graeme A. George

Emeritus Faculty Author Gallery

No abstract provided.


Polymer Science In Australia I. Sydney And Canberra, Otto Vogl, Donald H. Napper Nov 1994

Polymer Science In Australia I. Sydney And Canberra, Otto Vogl, Donald H. Napper

Emeritus Faculty Author Gallery

No abstract provided.


65. Ferenc Tudos, Otto Vogl Nov 1994

65. Ferenc Tudos, Otto Vogl

Emeritus Faculty Author Gallery

No abstract provided.


Connectivity And Performance Tradeoffs In The Cascade Correlation Learning Architecture, D. S. Phatak, I. Koren Nov 1994

Connectivity And Performance Tradeoffs In The Cascade Correlation Learning Architecture, D. S. Phatak, I. Koren

Computer Science Department Faculty Publication Series

The Cascade Correlation [1] is a very flexible, efficient and fast algorithm for supervised learning. It incrementally builds the network by adding hidden units one at a time, until the desired input/output mapping is achieved. It connects all the previously installed units to the new unit being added. Consequently, each new unit in effect adds a new layer and the fan–in of the hidden and output units keeps on increasing as more units get added. The resulting structure could be hard to implement in VLSI, because the connections are irregular and the fan-in is unbounded. Moreover, the depth or the …


Polymer Science In Australia Ii. Brisbane And Queensland, Otto Vogl, James H. O'Donnell, David J. T. Hill Oct 1994

Polymer Science In Australia Ii. Brisbane And Queensland, Otto Vogl, James H. O'Donnell, David J. T. Hill

Emeritus Faculty Author Gallery

No abstract provided.


Xith Symposium On Cationic Polymerization And Related Ionic Processes, Otto Vogl, Ivan M. Panayotov, Christo B. Tsvetanov Oct 1994

Xith Symposium On Cationic Polymerization And Related Ionic Processes, Otto Vogl, Ivan M. Panayotov, Christo B. Tsvetanov

Emeritus Faculty Author Gallery

No abstract provided.


9th Bratislava Conference On Modification Of Thermoplastic Polymers, Otto Vogl, Lyda Matisova-Rychla Sep 1994

9th Bratislava Conference On Modification Of Thermoplastic Polymers, Otto Vogl, Lyda Matisova-Rychla

Emeritus Faculty Author Gallery

No abstract provided.


Polymer Science In Australia Iii. Csiro And Other Government Institutions, Otto Vogl, Ezio Rizzardo, Carolyn Morris Sep 1994

Polymer Science In Australia Iii. Csiro And Other Government Institutions, Otto Vogl, Ezio Rizzardo, Carolyn Morris

Emeritus Faculty Author Gallery

No abstract provided.


Determination Of Rate Constants By A Double-Line Flow-Injection Method Incorporating A Well-Stirred Tank Reactor, Rt Echols, Jf Tyson Jan 1994

Determination Of Rate Constants By A Double-Line Flow-Injection Method Incorporating A Well-Stirred Tank Reactor, Rt Echols, Jf Tyson

Chemistry Department Faculty Publication Series

No abstract provided.


Evaluation Of The Precision Of The Flow Injection Doublet Peak, Julian Tyson, Rt Echols Jan 1994

Evaluation Of The Precision Of The Flow Injection Doublet Peak, Julian Tyson, Rt Echols

Chemistry Department Faculty Publication Series

The factors affecting the precision of the flow injection doublet peak method are discussed with particular reference to the contribution from the uncertainty associated with the calibration procedure. A single-line flow injection manifold was used in which the concentration gradients were generated by alternating helical reactors and the reaction products were monitored by a simple detector incorporating diodes as light source and intensity transducer. The reactions between lanthanum and Methyl Thymol Blue and between sodium hydroxide and hydrochloric acid in the presence of Bromothymol Blue were used. Optimization studies involved the method of steepest ascent, two figures of merit (the …


Comparison Of Mixing Devices For Flow Injection Determinations Based On Doublet Peak Formation, Julian Tyson, Rt Echols Jan 1994

Comparison Of Mixing Devices For Flow Injection Determinations Based On Doublet Peak Formation, Julian Tyson, Rt Echols

Chemistry Department Faculty Publication Series

The well-stirred tank model accurately describes the separation (At) between flow-injection doublet peaks and has been found to be applicable to a variety of mixing devices that do not contain moving parts such as a magnetic follower. The reaction between lanthanum(III) and methyl thymol blue was used as a model reaction for a comparison study of mixing devices. Column and open-tubular reactors were included in the study. Mixing devices were compared on the basis of the straight line fit of At versus the natural logarithm of the concentration of injected La(III). The linearity of the At-ln[La(III)] plots was equivalent for …


Solid-State Microprocessor Controlled Detector For Doublet Peak Measurements In Flow Injection Analysis, Julian Tyson, A Murfin, M Conboy, M K. Carroll Jan 1994

Solid-State Microprocessor Controlled Detector For Doublet Peak Measurements In Flow Injection Analysis, Julian Tyson, A Murfin, M Conboy, M K. Carroll

Chemistry Department Faculty Publication Series

No abstract provided.


Flow Analysis. A Report On The 6th International Conference On Flow Analysis Held In Toledo, Spain, June 8-11, 1994, Julian Tyson Jan 1994

Flow Analysis. A Report On The 6th International Conference On Flow Analysis Held In Toledo, Spain, June 8-11, 1994, Julian Tyson

Chemistry Department Faculty Publication Series

No abstract provided.


Comparison Of The Maximum Sensitivity Of Different Flow Injection Manifold Configurations: Alternating Variable Search Optimization Of The Iron(Ii)/1,10-Phenanthroline System, Sj Chalk, Julian Tyson Jan 1994

Comparison Of The Maximum Sensitivity Of Different Flow Injection Manifold Configurations: Alternating Variable Search Optimization Of The Iron(Ii)/1,10-Phenanthroline System, Sj Chalk, Julian Tyson

Chemistry Department Faculty Publication Series

No abstract provided.


Flow Injection Reagent Introduction By Supported Liquid And Nafion Membranes: Determination Of Phosphate, Stuart J. Chalk, Julian Tyson Jan 1994

Flow Injection Reagent Introduction By Supported Liquid And Nafion Membranes: Determination Of Phosphate, Stuart J. Chalk, Julian Tyson

Chemistry Department Faculty Publication Series

The use of membrane tubing for the introduction of reagents for the determination of phosphate in waters by flow injection analysis was studied. The use of membranes eliminates the need for confluence points in the design of flow injection manifolds. This increases the sensitivity of the manifold by providing a sufficient reagent excess for the reaction without diluting the sample. Methods for the introduction of acid, molybdate and hydrazine were devised for the determination of phosphate by the Molybdenum Blue method. Several membranes were examined and Nafion and Accurel (microporous polypropylene) were found to be most useful. Molybdate introduction was …


Flow Injection Techniques, Julian Tyson Jan 1994

Flow Injection Techniques, Julian Tyson

Chemistry Department Faculty Publication Series

No abstract provided.


Diode-Laser-Based Detector For Doublet Peak Measurements In Flow Injection Analysis, Mary K. Carroll, Julian Tyson Jan 1994

Diode-Laser-Based Detector For Doublet Peak Measurements In Flow Injection Analysis, Mary K. Carroll, Julian Tyson

Chemistry Department Faculty Publication Series

No abstract provided.


Supersymmetry And Stationary Solutions In Dilaton-Axion Gravity, R Kallosh, David Kastor, T Ortín, T Torma Jan 1994

Supersymmetry And Stationary Solutions In Dilaton-Axion Gravity, R Kallosh, David Kastor, T Ortín, T Torma

Physics Department Faculty Publication Series

New stationary solutions of four-dimensional dilaton-axion gravity are presented, which correspond to the charged Taub-NUT and Israel-Wilson-Perjés (IWP) solutions of Einstein-Maxwell theory. The charged axion-dilaton Taub-NUT solutions are shown to have a number of interesting properties: (i) manifest SL(2,R) symmetry; (ii) an infinite throat in an extremal limit; (iii) the throat limit coincides with an exact CFT construction. The IWP solutions are shown to admit supersymmetric Killing spinors, when embedded in d=4,N=4 supergravity. This poses a problem for the interpretation of supersymmetric rotating solutions as physical ground states. In the context of 10-dimensional geometry, we show that dimensionally lifted versions …


Supersymmetric Self-Gravitating Solitons, G Gibbons, David Kastor, L London, P Townsend, Jennie Traschen Jan 1994

Supersymmetric Self-Gravitating Solitons, G Gibbons, David Kastor, L London, P Townsend, Jennie Traschen

Physics Department Faculty Publication Series

We show that the “instantonic” soliton of five-dimensional Yang-Mills theory and the closely related BPS monopole of four-dimensional Yang-Mills/Higgs theory continue to be exact static, and stable, solutions of these field theories even after the inclusion of gravitational, electromagnetic and, in the four-dimensional case, dilatonic interactions, provided that certain non-minimal interactions are included. With the inclusion of these interactions, which would be required by supersymmetry, these exact self-gravitating solitons saturate a gravitational version of the Bogomol'nyi bound on the energy of an arbitrary field configuration.


Pair Creation Of Dilaton Black Holes, F Dowker, J Gauntlett, David Kastor, Jennie Traschen Jan 1994

Pair Creation Of Dilaton Black Holes, F Dowker, J Gauntlett, David Kastor, Jennie Traschen

Physics Department Faculty Publication Series

We consider dilaton gravity theories in four spacetime dimensions parametrized by a constant a, which controls the dilaton coupling, and construct new exact solutions. We first generalize the C metric of Einstein-Maxwell theory (a=0) to solutions corresponding to oppositely charged dilaton black holes undergoing uniform acceleration for general a. We next develop a solution-generating technique which allows us to ‘‘embed’’ the dilaton C metrics in magnetic dilaton Melvin backgrounds, thus generalizing the Ernst metric of Einstein-Maxwell theory. By adjusting the parameters appropriately, it is possible to eliminate the nodal singularities of the dilaton C metrics. For a<1 (but not for a≥1), it is possible to further restrict the parameters so that the dilaton Ernst solutions have a smooth Euclidean section with topology S2×S2-{pt}, corresponding to instantons describing the pair production of dilaton black holes in a magnetic field. A different restriction on the parameters leads to smooth instantons for all values of a with topology S2×openR2.


The Reactions Gamma-Gamma-]Wl(+)Wl(-) And Gamma-Gamma-]Z(L)Z(L) In Su(N) Strongly Interacting Theories, Jf Donoghue, T Torma Jan 1994

The Reactions Gamma-Gamma-]Wl(+)Wl(-) And Gamma-Gamma-]Z(L)Z(L) In Su(N) Strongly Interacting Theories, Jf Donoghue, T Torma

Physics Department Faculty Publication Series

In theories in which the parameters of the low energy theory are not unique, perhaps having different values in different domains of the universe as is possible in some inflationary models, the fermion masses would be distributed with respect to some weight. In such a situation the specifics of the fermion masses do not have a unique explanation, yet the weight provides the visible remnant of the structure of the underlying theory. This paper introduces this concept of a weight for the distribution of masses and provides a quantitative estimate of it from the observed quarks and leptons. The weight …


Light Quark Masses And Mixing Angles, John Donoghue Jan 1994

Light Quark Masses And Mixing Angles, John Donoghue

Physics Department Faculty Publication Series

I review the present state of our knowledge about the masses and weak mixing elements of the u, d, s quarks. This is the written version of lectures given in the 1993 Theoretical Advanced Study Institute (TASI).


Dispersion-Relations And The Nucleon Polarizability, Br Holstein, Am Nathan Jan 1994

Dispersion-Relations And The Nucleon Polarizability, Br Holstein, Am Nathan

Physics Department Faculty Publication Series

Recent experimental results on the proton and neutron polarizabilities are examined from the point of view of backward dispersion relations. Results are found to be in reasonable agreement with the measured values. A rigorous relationship between the nucleon and pion polarizabilities is derived and shown to be in excellent agreement with several models.


Adiabatic Invariants In Stellar Dynamics .2. Gravitational Shocking, Md Weinberg Jan 1994

Adiabatic Invariants In Stellar Dynamics .2. Gravitational Shocking, Md Weinberg

Astronomy Department Faculty Publication Series

A new theory of gravitational shocking based on time-dependent perturbation theory shows that the changes in energy and angular momentum due to a slowly varying disturbance are not exponentially small for stellar dynamical systems in general. It predicts significant shock heating by slowly varying perturbations previously thought to be negligible according to the adiabatic criterion. The theory extends the scenarios traditionally computed only with the impulse approximation and is applicable to a wide class of disturbances. The approach is applied specifically to the problem of the disk shocking of star clusters.


Adiabatic Invariants In Stellar Dynamics .3. Application To Globular-Cluster Evolution, Md Weinberg Jan 1994

Adiabatic Invariants In Stellar Dynamics .3. Application To Globular-Cluster Evolution, Md Weinberg

Astronomy Department Faculty Publication Series

The previous two companion papers demonstrate that slowly varying perturbations do not result in adiabatic cutoffs and provide a formalism for computing the long term effects of time dependent perturbations on stellar systems. Here, the theory is implemented in Fokker Planck code and a suite of runs illustrating the effects of shock heating on globular cluster evolution are described. Shock heating alone results in a considerable mass loss for clusters with Rg < S kpc: a concentration c = 1.5 cluster with Rg = 8kpc loses up to 95% of the initial mass in 15 Gyr. Only those with concentration c < 1.3 survive disk shock inside of this radius. Other effects, such as mass loss by stellar evolution, will increase this survival bound. Loss of the initial halo together with mass segregation leads to mass spectral induces, x, which may be considerably large than their initial values.


Kinematic Signature Of A Rotating Bar Near A Resonance, Md Weinberg Jan 1994

Kinematic Signature Of A Rotating Bar Near A Resonance, Md Weinberg

Astronomy Department Faculty Publication Series

There have been several recent suggestions that the Milky Way has rotating bar-like features based on HI and star count data. In this paper, I show that such features cause distinctive stellar kinematic signatures near OLR and ILR. The effects of these resonances may be observable far from the peak density of the pattern and relatively nearby the solar position. The details of the kinematic signatures depend on the evolutionary history of the ‘bar’ and therefore velocity data, both systemic and velocity dispersion, may be used to probe the evolutionary history as well as the present state of the Galaxy. …


Leading Quantum Correction To The Newtonian Potential, Jf Donoghue Jan 1994

Leading Quantum Correction To The Newtonian Potential, Jf Donoghue

Physics Department Faculty Publication Series

I argue that the leading quantum corrections, in powers of the energy or inverse powers of the distance, may be computed in quantum gravity through knowledge of only the low-energy structure of the theory. As an example, I calculate the leading quantum corrections to the Newtonian gravitational potential.