Physical Sciences and Mathematics Commons^™

Internal Waves Revealed By Synthetic Aperture Radar (Sar) Imagery In The Vicinity Of The Eastern Cretan Arc Straits (Eastern Mediterranean), Adonis Velegrakis, E. Oikonomou, A. Theocharis, M Collins, H Kontoyannis, V Papadopoulos, George Voulgaris, T. Wells, E. Balopoulos

George Voulgaris

Internal waves have been detected on ERS-1 SAR images obtained during late summer over the eastern Cretan Straits, an area characterised by complex regional physiography, bottom topography, flow regime and stratification patterns of the upper part of the water column. Analysis of the imaged characteristics of the internal waves has revealed a strong diversity in form, propagation direction and type of sea surface modulation, which indicates various mechanisms of generation. Analysis of the currents recorded over the area shows that, although semi-diurnal tidal currents are present, these are of low magnitude in comparison with the overall flow and, therefore, tidal …

Rule-Mitigated Collaboration Technology, Carl Chang, Alexei Vorontsov, Jia Zhang, Francis Quek

Jia Zhang

No abstract provided.

Accelerated Assessment And Selection Of Design Concepts In The Presence Of Qualitative Uncertainty And Imprecision, D. Verma, Caroline Lubert, W. Fabrycky

Caroline P Lubert

No abstract provided.

Fuzzy Neural Network Models For Supervised Classification: Multispectral Image Analysis, Arun D. Kulkarni, Kamlesh Lulla

Arun Kulkarni

No abstract provided.

A Perturbation Of A Periodic Hamiltonian System, Gregory S. Spradlin

Gregory S. Spradlin

No abstract provided.

Phase Imaging: Deep Or Superficial?, Nancy Burnham, O Behrend, L Odoni, J Loubet

Nancy A. Burnham

Phase images acquired while intermittently contacting a sample surface with the tip of an atomic force microscope cantilever are not easy to relate to material properties. We have simulated dynamic force curves and compared simulated with experimental results. For some cantilever–sample combinations, the interaction remains a surface effect, whereas for others, the tip penetrates the sample significantly. Height artifacts in the “topography” images, and the role of the sample stiffness, work of adhesion, damping, and topography in the cantilever response manifest themselves to different extents depending on the indentation depth.

Transparent Stacked Organic Light Emitting Devices. I. Design Principles And Transparent Compound Electrodes, G. Gu, G. Parthasarathy, P. E. Burrows, Peifang Tian, I. G. Hill, A. Kahn, S. R. Forrest

Peifang Tian

Vertical stacking of organic light emitting devices (OLEDs) that emit the three primary colors is a means for achieving full-color flat panel displays. The physics, performance, and applications of stacked OLEDs (SOLEDs) are discussed in this and the following paper (Papers I and II, respectively). In Paper I, we analyze optical microcavity effects that can distort the emission colors of SOLEDs if not properly controlled, and describe design principles to minimize these parasitic effects. We also describe the fabrication and operating characteristics of transparent contacts that are an integral part of SOLEDs. We demonstrate that both metal-containing and metal-free transparent …

Transparent Stacked Organic Light Emitting Devices. Ii. Device Performance And Applications To Displays, G. Gu, G. Parthasarathy, Peifang Tian

Peifang Tian

Vertical stacking of organic light emitting devices (OLEDs) that emit the three primary colors is shown to be a means for achieving efficient and bright full-color displays. In Paper I, we addressed stacked OLED (SOLED) design and fabrication principles to optimize emission colors, operating voltage, and efficiency. Here, we present results on two different (metal-containing and metal-free cathode) SOLED structures that exhibit performance suitable for many full-color display applications. The operating voltages at 10 mA/cm2 (corresponding to video display brightnesses) are 6.8, 8.5, and 12.1 V for the red (R), green (G), and blue (B) elements of the metal-containing SOLED, …

Development And Student Use Of Web-Based Prelabs In Analytical Chemistry Courses, Mark Anderson, Brian Tissue

Mark R. Anderson

No abstract is currently available.

Illuminesse :Possible Side Effects & Benefits, Marlenehull Marlenehull

marlenehull marlenehull

Ab Initio Calculation Of 81Br Nqr Transition Frequencies Of Brominated Aromatics (Flame Retardants), Chris R. Harwell, Anthony A. Mrse, Leslie G. Butler, Randall W. Hall

Randall W. Hall

Regional Hydrology Of The Dixie Valley Geothermal Field, Nevada: Preliminary Interpretations Of Chemical And Isotopic Data, Gregory Nimz, Cathy Janik, Fraser Goff, Charles Dunlap, Mark Huebner, Dale Counce, Stuart Johnson

Charles Dunlap

Chemical and isotopic analyses of Dixie Valley regional waters indicate several distinct groups ranging in recharge age from Pleistocene (<20 ka) to recent (<50a). Valley groundwater is older than water from perennial springs and artesian wells in adjacent ranges, with Clan Alpine range (east) much younger (most <50a) than Stillwater range (west; most > 1OOOa).Geothermal field fluids (-12-14 ka) appear derived from water similar in composition to non-thermal groundwater observed today in valley artesian wells (also -14 ka). Geothermal fluid interaction with mafic rocks (Humboldt Lopolith) appears to be common, and significant reaction with granodiorite may also occur. Despite widespread occurrence of carbonate rocks, largescale chemical interaction appears minor. Age asymmetry of the ranges, more extensive interaction with deep- seated waters in the west, and distribution of springs and artesian wells suggest the existence …

Glueball Production In Peripheral Heavy-Ion Collisions, Alec Schramm

Alec J Schramm

The method of equivalent quanta is applied both to photon-photon and, by analogy, to double pomeron exchange in heavy-ion collisions. This Weizsäcker-Williams approach is used to calculate production cross sections for the glueball candidate fJ(1710) meson via photon-photon and pomeron-pomeron fusion in peripheral heavy-ion collisions at both RHIC and LHC energies. The impact parameter dependence for total and elastic cross sections is presented, and compared with results for proton-proton collisions.

Precise, Scalable Shadow Mask Patterning Of Vacuum-Deposited Organic Light Emitting Devices, Peifang Tian, V. Bulovic, P. Burrows, G. Gu, S. Forrest, T. Zhou

Peifang Tian

We demonstrate a scheme to pattern vacuum-deposited, small molecular weight organic light emitting diodes 􏰉OLEDs􏰀. Both the organic thin films and the metallic electrodes are patterned by shifting the position of a single shadow mask which accompanies the substrate throughout the deposition process. A full color, stacked OLED 􏰉SOLED􏰀 has been fabricated using this technique. The substrate movement relative to the mask was manually controlled to a root mean square accuracy of 􏰑8 􏰇m using a mask translating fixture. The performance of the patterned SOLED is comparable with that of devices fabricated by conventional, low tolerance methods. The limits to …

Computational Complexity For Continuous Time Dynamics, Hava Siegelmann, Asa Ben-Hur, Shmuel Fishman

Hava Siegelmann

Dissipative flows model a large variety of physical systems. In this Letter the evolution of such systems is interpreted as a process of computation; the attractor of the dynamics represents the output. A framework for an algorithmic analysis of dissipative flows is presented, enabling the comparison of the performance of discrete and continuous time analog computation models. A simple algorithm for finding the maximum of n numbers is analyzed, and shown to be highly efficient. The notion of tractable (polynomial) computation in the Turing model is conjectured to correspond to computation with tractable (analytically solvable) dynamical systems having polynomial complexity.

Back To Basics – Statistics For Logisticians, Caroline Lubert

Caroline P Lubert

No abstract provided.

The Discovery-Oriented Approach To Organic Chemistry. 2. Selectivity In Alcohol Oxidation. An Exercise In 1H Nmr Spectroscopy For Sophomore Organic Laboratories, Ram S. Mohan, Steven R. Shadwick

Ram S. Mohan

An Explanation Of Observed Trends In The X-Ray Emission From Single Wolf-Rayet Stars., R. Ignace, L. M. Oskinova

Richard Ignace

The O and early B star winds show empirical correlations between X-ray (L_x) and Bolometric (L_Bol) luminosity as well as wind properties such as wind momentum and wind kinetic energy. Wolf-Rayet stars do not. We discuss scaling relations to qualitatively explain this lack of correlation among the WR winds and to quantitatively reproduce the observed ratio of X-ray luminosities between the N-rich WN types and C-rich WC types. If (a) the filling factor of hot X-ray emitting gas varies as (M⊙/v_\infty)(-1) for stars of different mass loss and terminal speed and (b) the ambient Wolf-Rayet wind component is optically thick …

The Hanle Effect As A Diagnostic Of Magnetic Fields In Stellar Envelopes Ii. Some Theoretical Results For Resolved Line Profiles., R. Ignace, J. P. Cassinelli, K. H. Nordsieck

Richard Ignace

A magnetic field diagnostic of stellar winds that uses the Hanle effect is discussed. This diagnostic pertains to the modification of resonance-line-scattering polarization in the presence of magnetic fields. The case for resolved polarized profiles of optically thin emission lines is considered, and some analytic results for an expanding equatorial disk are derived. Numerical results for a dipole magnetic field embedded in a spherical outflow are also presented. Although the considerations are somewhat simplified, the primary conclusion is that the modification or creation of line profile polarization by the Hanle effect can be used to discriminate between different magnetic field …

Scattering Polarization Due To Light Source Anisotropy I. Large Spherical Envelope., M. B. Al-Malki, J. F. L. Simmons, R. Ignace, J. C. Brown, D. Clarke

Richard Ignace

Expressions are developed for the flux and polarization of radiation scattered by a spherically symmetric envelope for a central point stellar light source that radiates anisotropically. These are obtained in terms of the components of the spherical harmonics of the flux anisotropy from the source. Such anisotropy can arise from stellar spots, or from distortion of the star through rotation, pulsation, or magnetic effects. Explicit expressions for the Stokes parameters are obtained in the case of an ellipsoidal star of uniform surface brightness. It is thus shown that even when the scattering envelope is spherical, observationally significant polarization can arise …

Probabilistic Crowding: Deterministic Crowding With Probabilistic Replacement, Ole J. Mengshoel, David E. Goldberg

Ole J Mengshoel

This paper presents a novel niching algorithm, probabilistic crowding. Like its predecessor deterministic crowding, probabilistic crowding is fast, simple, and requires no parameters beyond that of the classical GA. In probabilistic crowding, subpopulations are maintained reliably, and we analyze and predict how this maintenance takes place.

This paper also identifies probabilistic crowding as a member of a family of algorithms, which we call integrated tournament algorithms. Integrated tournament algorithms also include deterministic crowding, restricted tournament selection, elitist recombination, parallel recombinative simulated annealing, the Metropolis algorithm, and simulated annealing.

Phd Thesis (Doctorat De Spécialité): Université De Ouagadougou, 1999. Dr. Mamoudou H. Dicko. Purification Et Propriétés Physico-Chimiques Des Enzymes De Curculigo Pilosa, Gladiolus Klattianus Et Boscia Senegalensis Catalysant L'Hydrolyse Des Polysaccharides (Amidon Et Béta-Glucanes), Mamoudou H. Dicko Prof.

Pr. Mamoudou H. DICKO, PhD

The objective of this study was the research of novel and inexpensive sources of polysaccharides degrading enzymes such as amylases and glucanases from local plants in order to justify their biotechnological applications. The isolation of two l3-amylases and an endo-1,3-ß-D-glucanase was reached using common protein purification methods such as buffer extraction, ammonium sulfate fractionation, ionexchange and gel filtration chromatographies. The methods used were simple and easily reproducible, suggesting the possibilfty of large-scale production. ln the crude extract of Curculigo pilosa tuber, only ß-amylase was detected as starch degrading enzyme and its activity was approximately 282 Uig of fresh material. The …

Reference Materials For Calorimetry And Differential Thermal Analysis, R. Sabbah, An Xu-Wu, J.S. Chickos, M.L.Planas Leitão, M.V. Roux, L.A. Torres

James Chickos

No abstract provided.

Voltammetry Of Metallofullerenes And Higher Fullerenes, Mark Anderson, Harry Dorn, Steven Stevenson, Susanne Dana

Mark R. Anderson

No abstract is currently available.

“Every Breath You Take... ”: The Demographics Of Toxic Air Releases In Southern California, James Sadd, Manuel Pastor, J. Boer, Lori Snyder

James Sadd

In this article, the authors investigate the relationship between ethnicity and potential environmental hazards in the metropolitan Los Angeles area. Using a variety of techniques, including geographic information systems (GIS) mapping, univariate comparisons, and logit, ordered logit, and tobit regression analysis, the authors find that, even controlling for other factors such as income and the extent of manufacturing employment and land use, minority residents tend to be disproportionately located in neighborhoods surrounding toxic air emissions. The results generally support the propositions of the proponents of “environmental justice”; in the conclusion, they consider what this might mean for urban land use …

Statistics For Logisticians – Back To Basics, Caroline Lubert

Caroline P Lubert

No abstract provided.

The Correlation Of Physical Properties Of Organic Molecules With Computed Molecular Surface Areas., Robert Mebane, Shannon Schanley, Thomas Rybolt, Chrystal Bruce

Chrystal D. Bruce

The objective of this paper is to show that a student's understanding of molecular properties can be enhanced with the study of molecular surface areas obtained from readily available molecular modeling software.

Radiocarbon Chronology And Δ13c Analysis Of Mid-To Late-Holocene Aeolian Environments, Guadalupe Mountains National Park, Texas, Usa, David Wilkins, Donald Currey

David E. Wilkins

The Red Dunes of Guadalupe Mountains National Park are quartzose sand sheets and dunes stabilized by sparse plant cover. Stratigraphy, radiocarbon dating, and δ13C analysis were examined in two of the larger arroyos for correlating evidence of aeolian deposition, which in this basin is taken as an indication of arid conditions. Four quartz-sand lithostratigraphic units, representing intervals of aeolian activity, are identified. Radiocarbon dates provide constraint on the timing of the three youngest quartz-sand units. A mid-Holocene aeolian interval, represented by a single radiocarbon date of 6350± 70 BP, is interpreted as transitional to an altithermal regime. A neopluvial period, …

Discontinuities In Recurrent Neural Networks, R. Gavaldà, Hava Siegelmann

Hava Siegelmann

This article studies the computational power of various discontinuous real computational models that are based on the classical analog recurrent neural network (ARNN). This ARNN consists of finite number of neurons; each neuron computes a polynomial net function and a sigmoid-like continuous activation function. We introduce arithmetic networks as ARNN augmented with a few simple discontinuous (e.g., threshold or zero test) neurons. We argue that even with weights restricted to polynomial time computable reals, arithmetic networks are able to compute arbitrarily complex recursive functions. We identify many types of neural networks that are at least as powerful as arithmetic nets, …

The Discovery-Oriented Approach To Organic Chemistry 1. Nitration Of Unknown Organic Compounds. An Exercise In 1H Nmr And 13C Nmr Spectroscopy For Sophomore Organic Laboratories, Ram S. Mohan, Sonia R. Mcelveen, Kostas Gavardinas, Jean A. Stamberger

Ram S. Mohan