SUBSHIFTS AND PERFORATION JULIEN GIOL AND DAVID KERR
Kerr, David
SUBSHIFTS AND PERFORATION JULIEN GIOL AND DAVID KERR Abstract. We demonstrate that the perforative work [29] showed that the perforation that can be observed in the ordered K0 group of certain manifolds. As a consequence of the perforation in K0, Villadsen's C-algebra fails to Date: September 8, 2008. 2000 Mathematics
Yates, D.N. Jr.; Myers, W.D.
1991-11-26T23:59:59.000Z
This patent describes a perforating gun for insertion in a wellbore into a formation. It includes a tubular housing and a tubular element, defining a flow passage.
Right-Sided Sigmoid Diverticular Perforation
Little, Andrew; Culver, Andrew
2012-01-01T23:59:59.000Z
Sigmoid Diverticular Perforation Andrew Little, MS Andyobstruction, bleeding, perforation, and colonic abscess.less common complication is perforation with formation of an
Donovan, J.F.; Naquin, M.J.
1991-12-31T23:59:59.000Z
This patent describes a system for preparing a formation to allow hydrocarbons to be produced from a well. It comprises an elongated perforating gun; means extending from the outer periphery of the gun, in a generally radial direction from its longitudinal axis, for facilitating extraction of the gun from the well, the means operable when the gun is covered with a solid material delivered into the well and lodged between the formation and the gun; and the means imparting a longitudinal extractive force when the gun is rotated along its longitudinal axis.
Blunt Trauma Patient with Esophageal Perforation
Colak Oray, Nese; Sivrikaya, Semra; Bayram, Basak; Egeli, Tufan; Dicle, Oguz
2014-01-01T23:59:59.000Z
JA, Viste A. Esophageal perforation: diagnostic work-up andPatient with Esophageal Perforation clinical decision-makingBMJ. 2013;346:f3095. perforation in South of Sweden: results
Ungulate Carcasses Perforate Ecological Filters and Create
Ungulate Carcasses Perforate Ecological Filters and Create Biogeochemical Hotspots in Forest created unexpected disturbances that reduced herbaceous cover, which effectively perforated the herbaceous
Perforation of Inferior Vena Cava by Inferior Vena Cava Filter
Unterman, Sarah; Nair, Tad
2013-01-01T23:59:59.000Z
vena cava filter strut perforation discovered during rightin E mergency M edicine Perforation of Inferior Vena Cava bysuggestive of chronic perforation with no evidence of free
Handlebar Trauma Causing Small Bowel Hernia with Jejunal Perforation
Yaylac?, Serpil; Ercelik, Hasan; Seyit, Murat; Kocyigit, Ali; Serinken, Mustafa
2014-01-01T23:59:59.000Z
most common site of perforation, and peritoneal irritationhernia with bowel perforation presenting as a tensionBowel Hernia with Jejunal Perforation Serpil Yaylaci, MD*
Manifold Integration: Data Integration on Multiple Manifolds
Choi, Hee Youl
2011-08-08T23:59:59.000Z
MANIFOLD INTEGRATION: DATA INTEGRATION ON MULTIPLE MANIFOLDS A Dissertation by HEE YOUL CHOI Submitted to the O?ce of Graduate Studies of Texas A&M University in partial fulflllment of the requirements for the degree of DOCTOR OF PHILOSOPHY... May 2010 Major Subject: Computer Science MANIFOLD INTEGRATION: DATA INTEGRATION ON MULTIPLE MANIFOLDS A Dissertation by HEE YOUL CHOI Submitted to the O?ce of Graduate Studies of Texas A&M University in partial fulflllment of the requirements...
EFFECTIVE MACROSCOPIC DYNAMICS OF STOCHASTIC PARTIAL DIFFERENTIAL EQUATIONS IN PERFORATED
Duan, Jinqiao
EFFECTIVE MACROSCOPIC DYNAMICS OF STOCHASTIC PARTIAL DIFFERENTIAL EQUATIONS IN PERFORATED DOMAINS equation defined on a domain perforated with small holes or heterogeneities. The homogenized effective, effective macroscopic model, stochastic homogenization, white noise, probability distribution, perforated
Nasal septum perforation as the presenting sign of lupus erythematosus
Mascarenhas, R; Tellechea, O; Oliveira, H; Reis, JP; Cordeiro, M; Migueis, J
2005-01-01T23:59:59.000Z
A.R. Asymptomatic nasal septum perforation in Systemic LupusVachtenheim J, Grossmann J. Perforation of the nasal septum98. 6. Simpson J. Nasal-septum perforation in Systemic Lupus
High power laser perforating tools and systems
Zediker, Mark S; Rinzler, Charles C; Faircloth, Brian O; Koblick, Yeshaya; Moxley, Joel F
2014-04-22T23:59:59.000Z
ystems devices and methods for the transmission of 1 kW or more of laser energy deep into the earth and for the suppression of associated nonlinear phenomena. Systems, devices and methods for the laser perforation of a borehole in the earth. These systems can deliver high power laser energy down a deep borehole, while maintaining the high power to perforate such boreholes.
Tubing carried perforating gun with insulation jacket
Donovan, J.F.; Yates, D.N.
1991-05-21T23:59:59.000Z
This patent describes a method of insulating a tubing carried perforating gun which is run through a subterranean wellbore. It includes making up at the well surface a tubing string for introduction within the well, the tubing string carrying a perforating gun assembly.
A case of perforating necrobiosis lipoidica in an African American female
Abdulla, Farah R; Sheth, Pranav B
2008-01-01T23:59:59.000Z
lipoidica that have perforation as a characteristic change.report, all subsequent cases show perforation histologically
Author's personal copy Perforated diode neutron detector modules fabricated from
Shultis, J. Kenneth
Author's personal copy Perforated diode neutron detector modules fabricated from high Perforated detectors Perforated diodes a b s t r a c t Compact neutron detectors are being designed that are mass produced from high-purity Si wafers. Each detector has thousands of circular perforations etched
Body Force Model for the Aerodynamics of Inclined Perforated Surfaces
Liu, Feng
Body Force Model for the Aerodynamics of Inclined Perforated Surfaces Juntao Xiong, Andrew Johnson of perforated surfaces inclined to a freestream. The goal is to characterize the key parameters affecting perforations. The model simulates the effects of the perforated surfaces by locally applying a body force term
Sound radiation from a line forced perforated elastic sandwich panel
Sidorov, Nikita
Sound radiation from a line forced perforated elastic sandwich panel I. David Abrahams Department by altering the interior geometry, and perforations can be added to one or both sides. With perforations399 1990 devised an effective boundary condition for a perforated sandwich plate structure, valid
Zeghib, Abdelghani
Dynamics on Lorentz manifolds Abdelghani Zeghib Introduction Motivations and questions Examples Results Results Previous results Linear Dynamics General considerations Furstenberg Lemma Lorentz Dynamics://www.umpa.ens-lyon.fr/~zeghib/ (joint work with Paolo Piccione) #12;Dynamics on Lorentz manifolds Abdelghani Zeghib Introduction
Hildebrand, Richard J. (Edgemere, MD); Wozniak, John J. (Columbia, MD)
2001-01-01T23:59:59.000Z
A compressed gas storage cell interconnecting manifold including a thermally activated pressure relief device, a manual safety shut-off valve, and a port for connecting the compressed gas storage cells to a motor vehicle power source and to a refueling adapter. The manifold is mechanically and pneumatically connected to a compressed gas storage cell by a bolt including a gas passage therein.
Case of Urethral Foreign Body: IUD Perforation of the Bladder with Calculus Formation
Gillis, Erin; Chhiv, Nak; Kang, Sacha; Sayegh, Rocky; Lotfipour, Shahram
2006-01-01T23:59:59.000Z
N, Djahanbakhch O. Perforation of the uterus and colon byand partial uterine perforation and embedding followingW.Z. , Kutcher, R. ,: Uterine perforation and embedding by
The “Perforated City:” Leipzig’s Model of Urban Shrinkage Management
Florentin, Daniel
2010-01-01T23:59:59.000Z
adapt to shrinkage and perforation at an early stage in an2010 From Shrinkage to Perforation But the phenomenon tookand created a kind of “perforation” (Nuissl & Rink, 2004).
Incarcerated Diaphragmatic Hernia with Bowel Perforation Presenting as a Tension Pneumothorax
Offman, Ryan; Spencer, Ryan
2014-01-01T23:59:59.000Z
secondary to a colonic perforation during diagnosticHernia with Bowel Perforation Presenting as a Tensionempyema secondary to perforation of an incarcerated segment
Frobenius manifolds and algebraic integrability
L. K. Hoevenaars
2007-06-26T23:59:59.000Z
We give a short review of Frobenius manifolds and algebraic integrability and study their intersection. The simplest case is the relation between the Frobenius manifold of simple singularities, which is almost dual to the integrable open Toda chain. New types of manifolds called extra special Kaehler and special F-manifolds are introduced which capture the intersection.
Parameter Estimation for the Heat Equation on Perforated Domains
Parameter Estimation for the Heat Equation on Perforated Domains H.T. Banks1 , D. Cioranescu2 , A: Inverse problems, parameter estimation, perforated domains, homogeniza- tion, thermal diffusion, ordinary porous samples by use of solutions of a heat equation on a randomly perforated domain. As noted
Managing Performance vs. Accuracy Trade-offs With Loop Perforation
Polz, Martin
Managing Performance vs. Accuracy Trade-offs With Loop Perforation Stelios Sidiroglou Sasa-hoc, domain-specific techniques developed specifically for the computation at hand. Loop perforation provides of their iterations. A criticality testing phase filters out critical loops (whose perforation produces unacceptable
Acoustic Transmission Loss of Perforated Plates Vincent Phong1
Papamoschou, Dimitri
Acoustic Transmission Loss of Perforated Plates Vincent Phong1 and Dimitri Papamoschou2 University of California, Irvine, CA 92697, USA A study has been conducted on the acoustic response of perforated plates coefficient of the perforate. The theoretical analysis is based on planar wave propagation through a single
Parameter Estimation for the Heat Equation on Perforated Domains
Parameter Estimation for the Heat Equation on Perforated Domains H.T. Banks1 , D. Cioranescu2 , A for simulated data for heat flow in a porous medium. We consider data simulated from a model on a perforated Words: Inverse problems, parameter estimation, perforated domains, homogeniza- tion, thermal diffusion
Nambu-Goldstone explosion under brane perforation
D. V. Gal'tsov; E. Yu. Melkumova; S. Zamani-Mogaddam
2010-12-13T23:59:59.000Z
We show that perforation of the three-brane by mass impinging upon it from the five-dimensional bulk excites Nambu-Goldstone spherical wave propagating outwards with the velocity of light. It is speculated that such an effect can give rise to "`unmotivated" energy release events in the brane-world cosmological models.
Nambu-Goldstone explosion under brane perforation
Gal'tsov, D V; Zamani-Mogaddam, S
2010-01-01T23:59:59.000Z
We show that perforation of the three-brane by mass impinging upon it from the five-dimensional bulk excites Nambu-Goldstone spherical wave propagating outwards with the velocity of light. It is speculated that such an effect can give rise to "`unmotivated" energy release events in the brane-world cosmological models.
Djordjevic, A.
1983-12-27T23:59:59.000Z
A tool guide is described that makes possible the insertion of cleaning and/or inspection tools into a manifold pipe that will dislocate and extract the accumulated sediment in such manifold pipes. The tool guide basically comprises a right angled tube (or other angled tube as required) which can be inserted in a large tube and locked into a radially extending cross pipe by adjustable spacer rods and a spring-loaded cone, whereby appropriate cleaning tools can be inserted into the cross pipe for cleaning, inspection, etc. 3 figs.
Djordjevic, A.
1982-07-08T23:59:59.000Z
A tool guide that makes possible the insertion of cleaning and/or inspection tools into a manifold pipe that will dislocate and extract the accumulated sediment in such manifold pipes. The tool guide basically comprises a right angled tube (or other angled tube as required) which can be inserted in a large tube and locked into a radially extending cross pipe by adjustable spacer rods and a spring-loaded cone, whereby appropriate cleaning tools can be inserted into to cross pipe for cleaning, inspection, etc.
Dual manifold heat pipe evaporator
Adkins, Douglas R. (Albuquerque, NM); Rawlinson, K. Scott (Albuquerque, NM)
1994-01-01T23:59:59.000Z
An improved evaporator section for a dual manifold heat pipe. Both the upper and lower manifolds can have surfaces exposed to the heat source which evaporate the working fluid. The tubes in the tube bank between the manifolds have openings in their lower extensions into the lower manifold to provide for the transport of evaporated working fluid from the lower manifold into the tubes and from there on into the upper manifold and on to the condenser portion of the heat pipe. A wick structure lining the inner walls of the evaporator tubes extends into both the upper and lower manifolds. At least some of the tubes also have overflow tubes contained within them to carry condensed working fluid from the upper manifold to pass to the lower without spilling down the inside walls of the tubes.
Dual manifold heat pipe evaporator
Adkins, D.R.; Rawlinson, K.S.
1994-01-04T23:59:59.000Z
An improved evaporator section is described for a dual manifold heat pipe. Both the upper and lower manifolds can have surfaces exposed to the heat source which evaporate the working fluid. The tubes in the tube bank between the manifolds have openings in their lower extensions into the lower manifold to provide for the transport of evaporated working fluid from the lower manifold into the tubes and from there on into the upper manifold and on to the condenser portion of the heat pipe. A wick structure lining the inner walls of the evaporator tubes extends into both the upper and lower manifolds. At least some of the tubes also have overflow tubes contained within them to carry condensed working fluid from the upper manifold to pass to the lower without spilling down the inside walls of the tubes. 1 figure.
Perforation of domain wall by point mass
D. V. Gal'tsov; E. Yu. Melkumova; P. A. Spirin
2013-12-30T23:59:59.000Z
We investigate collision of a point particle and an infinitely thin planar domain wall interacting gravitationally within the linearized gravity in Minkowski space-time of arbitrary dimension. In this setting we are able to describe analytically the perforation of the wall by an impinging particle, showing that it is accompanied by excitation of the spherical shock branon wave propagating outwards with the speed of light. Formally, the shock wave is a free solution of the branon wave equation which has to be added to ensure the validity of the retarded solution at the perforation point. Physically, the domain wall gets excited due to the shake caused by an instantaneous change of sign of the repulsive gravitational force. This effect is shown to hold, in particular, in four space-time dimensions, being applicable to the problem of cosmological domain walls.
Perforation of domain wall by point mass
Gal'tsov, D V; Spirin, P A
2013-01-01T23:59:59.000Z
We investigate collision of a point particle and an infinitely thin planar domain wall interacting gravitationally within the linearized gravity in Minkowski space-time of arbitrary dimension. In this setting we are able to describe analytically the perforation of the wall by an impinging particle, showing that it is accompanied by excitation of the spherical shock branon wave propagating outwards with the speed of light. Formally, the shock wave is a free solution of the branon wave equation which has to be added to ensure the validity of the retarded solution at the perforation point. Physically, the domain wall gets excited due to the shake caused by an instantaneous change of sign of the repulsive gravitational force. This effect is shown to hold, in particular, in four space-time dimensions, being applicable to the problem of cosmological domain walls.
Perforation of thin unreinforced concrete slabs
Cargile, J.D. [Army Engineer Waterways Experiment Station, Vicksburg, MS (United States); Giltrud, M.E. [Defense Nuclear Agency, Washington, DC (United States); Luk, V.K. [Sandia National Labs., Albuquerque, NM (United States)
1993-10-01T23:59:59.000Z
This report discusses fourteen tests which were conducted to investigate the perforation of thin unreinforced concrete slabs. The 4340-steel projectile used in the test series is 50.8 mm in diameter, 355.6 mm in length, has a mass of 2.34 kg. and an ogive nose with caliber radius head of 3. The slabs, contained within steel culverts, are 1.52 m in diameter and consist of concrete with a nominal unconfined compressive strength of 38.2 MPa and maxima aggregate size of 9.5 mm. Slab thicknesses are 284.4, 254.0, 215.9 and 127.0 mm. Tests were conducted at impact velocities of about 313 m/s on all slab thicknesses and about 379 and 471 m/s on the 254.0-mm-thick slab. All tests were conducted at normal incidence to the slab. All tests were conducted at normal incidence to the slab. Information obtained from the tests used to determine the loading (deceleration) on the projectile during the perforation process, the velocity-displacement of the projectile as it perforated the slab, and the projectile position as damage occurred on the backface of the slab. The test projectile behaved essentially as a rigid body for all of the tests.
Dispersant solutions for dispersing hydrocarbons
Tyndall, R.L.
1997-03-11T23:59:59.000Z
A dispersant solution includes a hydrocarbon dispersing solution derived from a bacterium from ATCC 75527, ATCC 75529, or ATCC 55638.
Dispersant solutions for dispersing hydrocarbons
Tyndall, Richard L. (Clinton, TN)
1997-01-01T23:59:59.000Z
A dispersant solution includes a hydrocarbon dispersing solution derived from a bacterium from ATCC 75527, ATCC 75529, or ATCC 55638.
Miniter, Una; Bae-Harboe, Yoon-Soo Cindy; Powers, Jennifer G; Campbell, Shannon M; Goldberg, Lynne J
2012-01-01T23:59:59.000Z
adult related to bowel perforation: Report and review of thewho expired from bowel perforation. CONCLUSIONS: Severeischemia and foci of perforation of the jejunum and ileum, a
Pressure enhanced penetration with shaped charge perforators
Glenn, Lewis A. (Danville, CA)
2001-01-01T23:59:59.000Z
A downhole tool, adapted to retain a shaped charge surrounded by a superatmospherically pressurized light gas, is employed in a method for perforating a casing and penetrating reservoir rock around a wellbore. Penetration of a shaped charge jet can be enhanced by at least 40% by imploding a liner in the high pressure, light gas atmosphere. The gas pressure helps confine the jet on the axis of penetration in the latter stages of formation. The light gas, such as helium or hydrogen, is employed to keep the gas density low enough so as not to inhibit liner collapse.
Einstein manifolds with skew torsion
Ilka Agricola; Ana Cristina Ferreira
2013-02-15T23:59:59.000Z
This paper is devoted to the first systematic investigation of manifolds that are Einstein for a connection with skew symmetric torsion. We derive the Einstein equation from a variational principle and prove that, for parallel torsion, any Einstein manifold with skew torsion has constant scalar curvature; and if it is complete of positive scalar curvature, it is necessarily compact and it has finite first fundamental group. The longest part of the paper is devoted to the systematic construction of large families of examples. We discuss when a Riemannian Einstein manifold can be Einstein with skew torsion. We give examples of almost Hermitian, almost metric contact, and G2 manifolds that are Einstein with skew torsion. For example, we prove that any Einstein-Sasaki manifold and any 7-dimensional 3-Sasakian manifolds admit deformations into an Einstein metric with parallel skew torsion.
Rinard, Martin
Probabilistic Accuracy Bounds for Perforated Programs A New Foundation for Program Analysis, Accuracy, Verification, Program Analysis, Program Transformation Keywords Loop Perforation, Program an inherent perfor- mance versus accuracy trade-off -- the more computational re- sources (such as time
Stress computations on perforated polygonal domains Jonas Englund and Johan Helsing
Helsing, Johan
Stress computations on perforated polygonal domains Jonas Englund and Johan Helsing Numerical perforated with 1170 holes are presented. The general usefulness of integral equation methods is discussed
Method and apparatus for selective retraction of a tubing carried perforating gun
Rubbo, R.P.
1990-12-25T23:59:59.000Z
This patent describes apparatus for telescopically retracting a subterranean well tubing carried perforating gun.
Modeling of Microwave Ovens with Perforated Metal Walls Erin M. Kiley and Vadim V. Yakovlev
Yakovlev, Vadim
Modeling of Microwave Ovens with Perforated Metal Walls Erin M. Kiley and Vadim V. Yakovlev ovens with perforated regions of metal walls. The technique relies on replacement of perforated segments-parameters obtained by FDTD simulation of a perforated sheet in a waveguide. This approach is employed in FDTD
Finite-Element Investigation and Design Recommendations for Perforated Steel Plate Shear Walls
Bruneau, Michel
Finite-Element Investigation and Design Recommendations for Perforated Steel Plate Shear Walls.k.a. perforated SPSW . Finite element monotonic pushover analyses were conducted, first on a series of individual perforated strips with variation in perforation diameter, to develop a fundamental understanding
Evaluation of Perforated Carbonate Cores Under Acid Stimulation
Diaz, Nerwing Jose
2011-10-21T23:59:59.000Z
Although it has been shown that clean perforation tunnels facilitate the evolution of a single, deeper-penetrating wormhole, there are no reported applications of reactive shaped charges in carbonates prior to acid stimulation. The present study...
Strongly Perforated K0-Groups of Simple C ?-Algebras
K-theory (4) 15(1998), 307–322. [V]. Jesper Villadsen, Simple C*-algebras with perforation. J. Funct. Anal. (1) 154(1998), 110–116. Toftegaards Alle 26. 4 tv.
Impact perforation of monolithic polyethylene plates: projectile nose shape dependence
Mohagheghian, I.; McShane, G. J.; Stronge, W. J.
2015-02-12T23:59:59.000Z
. The perforation mechanisms and energy absorption of these PE plates are contrasted with those of thin aluminium alloy targets that have the same total mass. UHMWPE outperforms these metallic targets for all three projectile nose shapes. Finally, the influence...
Evaluation of Perforated Carbonate Cores Under Acid Stimulation
Diaz, Nerwing Jose
2011-10-21T23:59:59.000Z
Although it has been shown that clean perforation tunnels facilitate the evolution of a single, deeper-penetrating wormhole, there are no reported applications of reactive shaped charges in carbonates prior to acid stimulation. The present study...
The effect of perforation patterns upon well productivity
Neale, John William
1955-01-01T23:59:59.000Z
LIBRARY A 4N COLLEGE OF TEXAS THE EFFECT OF PERFORATION PATTERNS UPON WELL PRODUCTIVITT A Thesis By John N, Neale ~ ~ Submitted to the Graduate Sohool of the Agrioultural and Meohanioal College of Texas in partial fulfillment... of the requirements for the degree of EASTER OF SCIENCE August 1966 Na)or Subgeotg PETROLBUM ENGINEERING THE EFFEC1 OF PERFORATION IN. TTERNS UPON WELL PRODUCTIVITX 4, Thesis JOHN W, NEI, LE Approved as to style and oontent lg s 7. Chai man of ommi ttee H...
NEW RESULTS ON THE ASYMPTOTIC BEHAVIOUR OF DIRICHLET PROBLEMS IN PERFORATED DOMAINS
Garroni, Adriana
NEW RESULTS ON THE ASYMPTOTIC BEHAVIOUR OF DIRICHLET PROBLEMS IN PERFORATED DOMAINS GIANNI DAL MASO behaviour of the solutions of elliptic equations with Dirichlet boundary conditions in perforated domains
Characterization of cardiac lead perforation risk via a dynamic simulated environment
Rosario, Matthew J
2012-01-01T23:59:59.000Z
Delayed cardiac perforation is a serious medical condition where an implanted cardiac lead migrates through the heart wall, causing life-threatening complications. Where acute perforation occurs during implant, delayed ...
EQUALITY CONSTRAINTS, RIEMANNIAN MANIFOLDS AND ...
2007-07-27T23:59:59.000Z
Jul 27, 2007 ... Page 1 ... what a Riemannian manifold is, what a tangent space is, how to move .... Now, since M is a regular level set, we can do the same thing for any ...... defined geodesics as those paths on M who's lengths don't change.
Design and performance considerations for perforated semiconductor thermal-neutron detectors
Shultis, J. Kenneth
Design and performance considerations for perforated semiconductor thermal-neutron detectors J neutron detectors Solid state neutron detectors a b s t r a c t Perforated silicon structures backfilled. Although many perforated structures are possible, there are three fundamental designs that are studied
Perforated Layer Structures in Liquid Crystalline Rod-Coil Block Copolymers
Wan, Xin-hua
Perforated Layer Structures in Liquid Crystalline Rod-Coil Block Copolymers Kishore K. Tenneti of the tetragonal perforated layer structures in a series of rod- coil liquid crystalline block copolymers (BCPs microscopy (TEM) techniques were used to investigate these rod-coil molecules, and a perforated layer
Simulating Perforation of Thin Plates Using Molecular Dynamics Approach Anton M. Krivtsov
Krivtsov, Anton M.
1 Simulating Perforation of Thin Plates Using Molecular Dynamics Approach Anton M. Krivtsov or molecules, but as elements of the mesoscale level, such as material grains [4,5]. Fig.1: Oblique perforation of plate by ogive-nose projectile. This approach is used in the current work to simulate perforation
Strelniker, Yakov M.
Transmittance and transparency of subwavelength-perforated conducting films in the presence theoretically and numerically studied the transmission of light through a subwavelength-perforated metal film of a static magnetic field. Both the perforated and the homogeneous metal films are found to exhibit
Bruneau, Michel
Special Perforated Steel Plate Shear Walls with Reduced Beam Section Anchor Beams. I: Experimental presents results of an experimental investigation of specially detailed ductile perforated steel plate history of increasing displacements to a minimum drift of 3%. The perforated panel reduced the elastic
Numerical Investigation of the Acoustic Behavior of a Multi-perforated Liner
Eldredge, Jeff
Numerical Investigation of the Acoustic Behavior of a Multi-perforated Liner Jeff D. Eldredge, Stanford, CA, 94305, USA The acoustic response of a turbulent flow through an aperture in a multi-perforated, turbine, and the downstream-traveling sound created by the fan. In particular, multi-perforated liners
J. SPACECRAFT, VOL. 36, NO. 2: ENGINEERING NOTES 293 Fig. 2 Perforation into oblique plate.
Riabov, Vladimir V.
J. SPACECRAFT, VOL. 36, NO. 2: ENGINEERING NOTES 293 Fig. 2 Perforation into oblique plate. Oblique of perforation due to yaw alone into the oblique plate can be represented by Eq. (3), with P0 given by Eq. (1 of perforation vs range for combined pitching and yawing motion. With the plane of angular motion oriented 45 deg
Papamoschou, Dimitri
of Perforated Plates with Bias Flow Vincent Phong1 and Dimitri Papamoschou2 University of California, Irvine, CA perforated plates with bias flow. A theoretical model is proposed which characterizes the acoustic response downstream of the perforations. Experimental measurements of insertion loss are conducted in a specially
Large-Eddy Simulation of a Turbulent Flow around a Multi-Perforated Plate
Mendez, Simon
Large-Eddy Simulation of a Turbulent Flow around a Multi-Perforated Plate Simon Mendez1 , Franck and used in Reynolds-Averaged Navier-Stokes methods cannot predict momen- tum/heat transfer on perforated plate are reported. Large-Eddy Simulations of the flow created by an infinite multi-perforated plate
Two-parameter homogenization for a GL problem in a perforated domain
Berlyand, Leonid
Two-parameter homogenization for a GL problem in a perforated domain Leonid Berlyand(1) , Petru the notations: o = o, i = i so that A = o i. We next define a perforated domain A obtained by "punching" holes, a point x R2 and define Z = {m + x + P A}. Then the perforated domain is defined as follows: A = A \\ m
Special Perforated Steel Plate Shear Walls with Reduced Beam Section Anchor Beams. II: Analysis and
Bruneau, Michel
Special Perforated Steel Plate Shear Walls with Reduced Beam Section Anchor Beams. II: Analysis detailed ductile perforated steel plate shear walls SPSWs . These SPSWs had low yield strength steel infill, recommendations for the design of these special detailed perforated SPSWs are presented. DOI: 10.1061/ ASCE 0733
FINITE ELEMENT INVESTIGATION AND DESIGN RECOMMENDATIONS FOR PERFORATED STEEL PLATE SHEAR WALLS
Bruneau, Michel
FINITE ELEMENT INVESTIGATION AND DESIGN RECOMMENDATIONS FOR PERFORATED STEEL PLATE SHEAR WALLS of the behavior of unstiffened thin SPSW having a regular pattern of openings (a.k.a. perforated SPSW). Finite element monotonic pushover analyses were conducted, first on a series of individual perforated strips
Efficiency of perforated breakwater and associated energy dissipation
Ariyarathne, Hanchapola Appuhamilage
2008-10-10T23:59:59.000Z
The flow field behavior in the vicinity of a perforated breakwater and the efficiency of the breakwater under regular waves were studied. To examine the efficiency of the structure thirteen types of regular wave conditions with wave periods T = 1, 1...
Efficiency of perforated breakwater and associated energy dissipation
Ariyarathne, Hanchapola Appuhamilage
2009-05-15T23:59:59.000Z
The flow field behavior in the vicinity of a perforated breakwater and the efficiency of the breakwater under regular waves were studied. To examine the efficiency of the structure thirteen types of regular wave conditions with wave periods T = 1, 1...
Tubing pressurized firing apparatus for a tubing conveyed perforating gun
Davies, D. L.
1985-11-26T23:59:59.000Z
A tubing pressurized firing apparatus is shown for use with a tubing conveyed perforating gun of the type used to perforate a cased well bore. The firing apparatus has a tubular body with an upper end for connection in the well tubing string and with a lower end for connection to a well perforating gun. An inner mandrel is slidably mounted within the tubular body and has a ball seat formed in the interior bore thereof for receiving a ball dropped through the well tubing string. The ball and ball seat together form a pressure tight seal whereby tubing pressure in the well tubing string acts on the inner mandrel to slide the mandrel downwardly within the tubular body. A cocking mechanism located below the inner mandrel within the body includes a lockout member which is initially positioned between a detonating pin and a percussion detonator. The cocking mechanism is actuated by downward sliding movement of the inner mandrel to move the lockout member from between the detonating pin and percussion detonator whereby a subsequent release of tubing pressure and upward sliding movement of the inner mandrel exposes the detonating pin to the percussion detonator to actuate the detonator and fire the perforating gun.
Geometric control of failure behavior in perforated sheets
Michelle M. Driscoll
2014-11-20T23:59:59.000Z
Adding perforations to a continuum sheet allows new modes of deformation, and thus modifies its elastic behavior. The failure behavior of such a perforated sheet is explored, using a model experimental system: a material containing a one-dimensional array of rectangular holes. In this model system, a transition in failure mode occurs as the spacing and aspect ratio of the holes are varied: rapid failure via a running crack is completely replaced by quasi-static failure which proceeds via the breaking of struts at random positions in the array of holes. I demonstrate that this transition can be connected to the loss of stress enhancement which occurs as the material geometry is modified.
Apparatus and method for sealing perforated well casing
Blount, C.G.; Benham, R.A.; Brock, J.L.; Emerson, J.A.; Ferguson, K.R.; Scheve, D.F.; Schmidt, J.H.; Schuler, K.W.; Stanton, P.L.
1997-03-25T23:59:59.000Z
Perforations and other openings in well casings, liners and other conduits may be substantially blocked or sealed to prevent fluid flow between the casing or liner interior and an earth formation by placing a radially expansible sleeve adjacent the perforations or openings and urging the sleeve into forcible engagement with the casing or inner wall using an explosive charge. An apparatus including a radially contracted sleeve formed by a coiled plate member or a tubular member having flutes defined by external and internal folds, may be deployed into a well casing or liner through a production or injection tubing string and on the end of a flexible cable or coilable tubing. An explosive charge disposed on the apparatus and within the sleeve may be detonated to urge the sleeve into forcible engagement with the casing inner wall. 17 figs.
INVERSE PROBLEMS FOR EINSTEIN MANIFOLDS 1. Introduction ...
2008-12-11T23:59:59.000Z
principle is that Einstein's equation becomes a non-linear elliptic system with real ...... manifolds with boundary, Communications in Analysis and Geometry 11 ...
Temperature Driven Annealing of Perforations in Bicellar Model Membranes
Nieh, Mu-Ping [University of Connecticut, Storrs; Raghunathan, V.A. [Raman Research Institute, India; Pabst, Georg [Austrian Academy of Sciences, Graz, Austria; Harroun, Thad [Brock University, St. Catharines, ON, Canada; Nagashima, K [University of Toronto, Mississauga, ON, Canada; Morales, H [University of Toronto, Mississauga, ON, Canada; Katsaras, John [ORNL; Macdonald, P [University of Toronto, Mississauga, ON, Canada
2011-01-01T23:59:59.000Z
Bicellar model membranes composed of 1,2-dimyristoylphosphatidylcholine (DMPC) and 1,2-dihexanoylphosphatidylcholine (DHPC), with a DMPC/DHPC molar ratio of 5, and doped with the negatively charged lipid 1,2-dimyristoylphosphatidylglycerol (DMPG), at DMPG/DMPC molar ratios of 0.02 or 0.1, were examined using small angle neutron scattering (SANS), {sup 31}P NMR, and {sup 1}H pulsed field gradient (PFG) diffusion NMR with the goal of understanding temperature effects on the DHPC-dependent perforations in these self-assembled membrane mimetics. Over the temperature range studied via SANS (300-330 K), these bicellar lipid mixtures exhibited a well-ordered lamellar phase. The interlamellar spacing d increased with increasing temperature, in direct contrast to the decrease in d observed upon increasing temperature with otherwise identical lipid mixtures lacking DHPC. {sup 31}P NMR measurements on magnetically aligned bicellar mixtures of identical composition indicated a progressive migration of DHPC from regions of high curvature into planar regions with increasing temperature, and in accord with the 'mixed bicelle model' (Triba, M. N.; Warschawski, D. E.; Devaux, P. E. Biophys. J.2005, 88, 1887-1901). Parallel PFG diffusion NMR measurements of transbilayer water diffusion, where the observed diffusion is dependent on the fractional surface area of lamellar perforations, showed that transbilayer water diffusion decreased with increasing temperature. A model is proposed consistent with the SANS, {sup 31}P NMR, and PFG diffusion NMR data, wherein increasing temperature drives the progressive migration of DHPC out of high-curvature regions, consequently decreasing the fractional volume of lamellar perforations, so that water occupying these perforations redistributes into the interlamellar volume, thereby increasing the interlamellar spacing.
Regier, Terry
Poverty of the Stimulus? A Rational Approach Amy Perfors1 (perfors@mit.edu), Joshua B. Tenenbaum1, MIT; 2 Department of Psychology, University of Chicago Abstract The Poverty of the Stimulus (Po that these generalizations can best be explained by innate knowledge, known as the argument from the Poverty of the Stimulus
Perforated plates for cryogenic regenerators and method of fabrication
Hendricks, J.B.
1994-03-29T23:59:59.000Z
Perforated plates having very small holes with a uniform diameter throughout the plate thickness are prepared by a [open quotes]wire drawing[close quotes] process in which a billet of sacrificial metal is disposed in an extrusion can of the plate metal, and the can is extruded and restacked repeatedly, converting the billet to a wire of the desired hole diameter. At final size, the rod is then sliced into wafers, and the wires are removed by selective etching. This process is useful for plate metals of interest for high performance regenerator applications, in particular, copper, niobium, molybdenum, erbium, and other rare earth metals. Er[sub 3]Ni, which has uniquely favorable thermophysical properties for such applications, may be incorporated in regions of the plates by providing extrusion cans containing erbium and nickel metals in a stacked array with extrusion cans of the plate metal, which may be copper. The array is heated to convert the erbium and nickel metals to Er[sub 3]Ni. Perforated plates having two sizes of perforations, one of which is small enough for storage of helium, are also disclosed. 10 figures.
Perforated plates for cryogenic regenerators and method of fabrication
Hendricks, John B. (Huntsville, AL)
1994-01-01T23:59:59.000Z
Perforated plates (10) having very small holes (14) with a uniform diameter throughout the plate thickness are prepared by a "wire drawing" process in which a billet of sacrificial metal is disposed in an extrusion can of the plate metal, and the can is extruded and restacked repeatedly, converting the billet to a wire of the desired hole diameter. At final size, the rod is then sliced into wafers, and the wires are removed by selective etching. This process is useful for plate metals of interest for high performance regenerator applications, in particular, copper, niobium, molybdenum, erbium, and other rare earth metals. Er.sub.3 Ni, which has uniquely favorable thermophysical properties for such applications, may be incorporated in regions of the plates by providing extrusion cans (20) containing erbium and nickel metals in a stacked array (53) with extrusion cans of the plate metal, which may be copper. The array is heated to convert the erbium and nickel metals to Er.sub.3 Ni. Perforated plates having two sizes of perforations (38, 42), one of which is small enough for storage of helium, are also disclosed.
Simplicial isotopies in 3-manifolds
O'Donnell, Daniel Francis
1974-01-01T23:59:59.000Z
by Treybig [6] of a theorem by Moise [3]. To prove it, we need the following lemma and theorem. Lemma 3. 1. Let P be a polyhedral 2-sphere and let L (u) p be a family of planes in E normal to a given unit vector u so that (a) the vertices of P are a.... E. E. MOise, Affine structures in 3-manifoMs. II. Positional properties of 2-spheres, Ann. of Math. 55(1952), 172 - 176. 4. D. E. Sanderson, Isotopy in 3-manifolds. I. Isotopic deform- mations of 2-cells and 3-cells, Proc. Amer. Math. Soc. 8...
Method and apparatus for perforating at cutting with a solid fueled gas mixture
Woytek, A.J.; Lileck, J.T.; Steigerwalt, E.J.
1984-05-08T23:59:59.000Z
A method for cutting pipe casings and concrete liners or perforating the same and localized portions of surrounding strata in an earth bore is set forth wherein a gas phase cutting or perforating jet mixture of fluorine and nitrogen trifluoride is delivered to the cutting or perforation site from the decomposition of a solid, normally stable, perfluoroammonium salt. An appropriate apparatus for delivering the gas mixture of fluorine and nitrogen trifluoride from the salt is also disclosed.
Magnetic Resonance Imaging (MRI) of PEM Dehydration and Gas Manifold...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Resonance Imaging (MRI) of PEM Dehydration and Gas Manifold Flooding During Continuous Fuel Cell Operation. Magnetic Resonance Imaging (MRI) of PEM Dehydration and Gas Manifold...
Cottle, John Ernest
1948-01-01T23:59:59.000Z
of the question. Other difficulties encountered. in the use of large packed columns are the tendeno1es of the liquid to channel through the paoking and. of the packing to break down under high operating temperatures. Hubble cap plate columns are the most...- oulty in a perforated. plate column than in any other types' and. should oleaning 'be necessary it could, be aocomplished much more easily. It is also believed that high plate efficienoies could be o'btained with per- i'orated plates 'beoause...
Viscosity method for Homogenization of Parabolic Nonlinear Equations in Perforated Domains
Kim, Sunghoon
2011-01-01T23:59:59.000Z
In this paper, we develop a viscosity method for Homogenization of Nonlinear Parabolic Equations constrained by highly oscillating obstacles or Dirichlet data in perforated domains. The Dirichlet data on the perforated domain can be considered as a constraint or an obstacle. Homogenization of nonlinear eigen value problems has been also considered to control the degeneracy of the Porous medium equation in perforated domains. For the simplicity, we consider obstacles that consist of cylindrical columns distributed periodically and perforated domains with punctured balls. If the decay rate of the capac- ity of columns or the capacity of punctured ball is too high or too small, the limit of u\\k{o} will converge to trivial solutions. The critical decay rates of having nontrivial solution are obtained with the construction of barriers. We also show the limit of u\\k{o} satisfies a homogenized equation with a term showing the effect of the highly oscillating obstacles or perforated domain in viscosity sense.
Mode Evolution and Transmission Suppression in a Perforated Ultrathin Metallic Film in a perforated ultrathin metallic film (PUMF) with a periodic triangular array of holes. It is found for the future studies in PUMF-based structures and devices. Keywords Surface plasmon . Perforated ultrathin
Anomalous Near-Field Heat Transfer between a Cylinder and a Perforated Surface Alejandro W between a cylinder and a perforated surface depends nonmonotonically on their separation. This anomalous between a cylinder (or elongated object) and a perforated surface (e.g., a ring) can vary nonmonotonically
Mechanical seal having a single-piece, perforated mating ring
Khonsari, Michael M. (Baton Rouge, LA); Somanchi, Anoop K. (Fremont, CA)
2007-08-07T23:59:59.000Z
A mechanical seal (e.g., single mechanical seals, double mechanical seals, tandem mechanical seals, bellows, pusher mechanical seals, and all types of rotating and reciprocating machines) with reduced contact surface temperature, reduced contact surface wear, or increased life span. The mechanical seal comprises a rotating ring and a single-piece, perforated mating ring, which improves heat transfer by controllably channeling coolant flow through the single-piece mating ring such that the coolant is in substantially uniform thermal contact with a substantial portion of the interior surface area of the seal face, while maintaining the structural integrity of the mechanical seal and minimizing the potential for coolant flow interruptions to the seal face caused by debris or contaminants (e.g., small solids and trash) in the coolant.
Gauge Theories in Noncommutative Homogeneous Kähler Manifolds
Yoshiaki Maeda; Akifumi Sako; Toshiya Suzuki; Hiroshi Umetsu
2014-09-07T23:59:59.000Z
We construct a gauge theory on a noncommutative homogeneous K\\"ahler manifold, where we employ the deformation quantization with separation of variables for K\\"ahler manifolds formulated by Karabegov. A key point in this construction is to obtaining vector fields which act as inner derivations for the deformation quantization. We show that these vector fields are the only Killing vector fields. We give an explicit construction of this gauge theory on noncommutative ${\\mathbb C}P^N$ and noncommutative ${\\mathbb C}H^N$.
SUSY gauge theory on graded manifolds
G. Sardanashvily; W. Wachowski
2014-06-24T23:59:59.000Z
Lagrangian classical field theory of even and odd fields is adequately formulated in terms of fibre bundles and graded manifolds. In particular, conventional Yang-Mills gauge theory is theory of connections on smooth principal bundles, but its BRST extension involves odd ghost fields an antifields on graded manifolds. Here, we formulate Yang-Mills theory of Grassmann-graded gauge fields associated to Lie superalgebras on principal graded bundles. A problem lies in a geometric definition of odd gauge fields. Our goal is Yang--Mills theory of graded gauge fields and its BRST extension.
Stiefel and Grassmann manifolds in Quantum Chemistry
Eduardo Chiumiento; Michael Melgaard
2011-05-09T23:59:59.000Z
We establish geometric properties of Stiefel and Grassmann manifolds which arise in relation to Slater type variational spaces in many-particle Hartree-Fock theory and beyond. In particular, we prove that they are analytic homogeneous spaces and submanifolds of the space of bounded operators on the single-particle Hilbert space. As a by-product we obtain that they are complete Finsler manifolds. These geometric properties underpin state-of-the-art results on existence of solutions to Hartree-Fock type equations.
Anomalous Near-Field Heat Transfer between a Cylinder and a Perforated Surface
Rodriguez-Wong, Alejandro
We predict that the near-field radiative heat-transfer rate between a cylinder and a perforated surface depends nonmonotonically on their separation. This anomalous behavior, which arises due to evanescent-wave effects, ...
Numerical simulations of perforated plate stabilized premixed flames with detailed chemistry
Kedia, Kushal Sharad
2010-01-01T23:59:59.000Z
The objective of this work is to develop a high efficiency two-dimensional reactive flow solver to investigate perforated-plate stabilized laminar premixed flames. The developed code is used to examine the impact of the ...
Localization effect for a spectral problem in a perforated domain with Fourier boundary cconditions
Valeria Chiado Piat; Iryna Pankratova; Andrey Piatnitski
2012-11-16T23:59:59.000Z
We consider a homogenization of elliptic spectral problem stated in a perforated domain, Fourier boundary conditions being imposed on the boundary of perforation. The presence of a locally periodic coefficient in the boundary operator gives rise to the effect of a localization of the eigenfunctions. Moreover, the limit behaviour of the lower part of the spectrum can be described in terms of an auxiliary harmonic oscillator operator. We describe the asymptotics of the eigenpairs and derive the estimates for the rate of convergence.
A study of the effects of casing perforations on the production rates of wells
Sanderlin, James Lewis
1958-01-01T23:59:59.000Z
Resistance Values Used to Sinulate Well Bore plus Perfo'rations ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ o ~ ~ ~ ~ ~ $2 III Resistance Values Neasured Using Electrolytic Tank and Conductivity Bridge . . . ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ IV Resistance Values for Plush Perforations 34... coetsat by: ~ ad of Defer ?t AuSest 1958 TRBUL OP CONTEIES introduction snd Review of Literature Materials and Iquipaent . Procedure 6 Electrolytic Tank Electrical dnaloS Model Results snd Discussion of Results 10 Conclusions . *cknowled...
MATH 132: TOPOLOGY II: SMOOTH MANIFOLDS ANDREW COTTON-CLAY
Cotton-Clay, Andrew
MATH 132: TOPOLOGY II: SMOOTH MANIFOLDS ANDREW COTTON-CLAY 1. Introduction My Name: Andrew Cotton-Clay
Manifold gasket accommodating differential movement of fuel cell stack
Kelley, Dana A. (New Milford, CT); Farooque, Mohammad (Danbury, CT)
2007-11-13T23:59:59.000Z
A gasket for use in a fuel cell system having at least one externally manifolded fuel cell stack, for sealing the manifold edge and the stack face. In accordance with the present invention, the gasket accommodates differential movement between the stack and manifold by promoting slippage at interfaces between the gasket and the dielectric and between the gasket and the stack face.
Einstein Manifolds and Contact Geometry Charles P. Boyer Krzysztof Galicki
Einstein Manifolds and Contact Geometry Charles P. Boyer Krzysztof Galicki Abstract. We show that every KÂcontact Einstein manifold is SasakianÂEinstein and discuss several corollaries of this result. 1 types of Riemannian contact manifolds to construct Einstein metrics of positive scalar curvature
Drilling long geodesics in hyperbolic 3-manifolds K. Bromberg
Bromberg, Kenneth
Drilling long geodesics in hyperbolic 3-manifolds K. Bromberg September 22, 2006 1 Introduction to such a deformation as drilling and results which compare the geometry of the original manifold to the geometry of the drilled manifold as drilling theorems. The first results of this type are due to Hodgson and Kerckhoff
Test Report for Perforated Metal Air Transportable Package (PMATO) Prototype.
Bobbe, Jeffery G.; Pierce, Jim Dwight
2003-06-01T23:59:59.000Z
A prototype design for a plutonium air transport package capable of carrying 7.6 kg of plutonium oxide and surviving a ''worst-case'' plane crash has been developed by Sandia National Laboratories (SNL) for the Japan Nuclear Cycle Development Institute (JNC). A series of impact tests were conducted on half-scale models of this design for side, end, and comer orientations at speeds close to 282 m/s onto a target designed to simulate weathered sandstone. These tests were designed to evaluate the performance of the overpack concept and impact-limiting materials in critical impact orientations. The impact tests of the Perforated Metal Air Transportable Package (PMATP) prototypes were performed at SNL's 10,000-ft rocket sled track. This report describes test facilities calibration and environmental testing methods of the PMATP under specific test conditions. The tests were conducted according to the test plan and procedures that were written by the authors and approved by SNL management and quality assurance personnel. The result of these tests was that the half-scale PMATP survived the ''worst-case'' airplane crash conditions, and indicated that a full-scale PMATP, utilizing this overpack concept and these impact-limiting materials, would also survive these crash conditions.
Energy-momentum balance in particle - domain wall perforating collision
D. V. Gal'tsov; E. Yu. Melkumova; P. A. Spirin
2015-02-10T23:59:59.000Z
We investigate the energy-momentum balance in the perforating collision of a point particle with an infinitely thin planar domain wall within the linearized gravity in arbitrary dimensions. Since the metric of the wall increases with distance, the wall and the particle are never free, and their energy-momentum balance involves not only the instantaneous kinetic momenta, but also the non-local contribution of gravitational stresses. However, careful analysis shows that the stresses can be unambiguously divided between the colliding objects leading to definition of the gravitationally dressed momenta. These take into account for gravity in the same way as the potential energy does in the non-relativistic theory, but our treatment is fully relativistic. Another unusual feature of our problem is the non-vanishing flux of the total energy-momentum tensor through the lateral surface of the world tube. In this case the zero divergence of the energy-momentum tensor does not imply conservation of the total momentum defined as the integral over the space-like section of the tube. But one can still define the conservation low infinitesimally, passing to time derivatives of the momenta. Using this definition we establish the momentum balance in terms of the dressed particle and wall momenta.
Large-Scale Manifold Learning Ameet Talwalkar
California at Irvine, University of
Large-Scale Manifold Learning Ameet Talwalkar Courant Institute New York, NY ameet on spectral decom- position, we first analyze two approximate spectral decom- position techniques for large-dimensional embeddings for two large face datasets: CMU-PIE (35 thousand faces) and a web dataset (18 million faces). Our
DIRECT SEARCH METHODS OVER LIPSCHITZ MANIFOLDS 1 ...
2007-02-27T23:59:59.000Z
Page 1 ... (implicit) function theorem allows us to define a new problem on the tangent spaces of the manifold. .... modification to our algorithm in Procedure 2.1, though now the convergence analysis is done in TxM. .... First we'll concern ourselves with finding the implicit function ?(0, w). What ... The reason is, we don'
Collisions at infinity in hyperbolic manifolds
McReynolds, D B; Stover, Matthew
2012-01-01T23:59:59.000Z
For a complete, finite volume real hyperbolic n-manifold M, we investigate the map between homology of the cusps of M and the homology of $M$. Our main result provides a proof of a result required in a recent paper of Frigerio, Lafont, and Sisto.
A Generalized Construction of Mirror Manifolds
P. Berglund; T. Hübsch
1992-01-09T23:59:59.000Z
We generalize the known method for explicit construction of mirror pairs of $(2,2)$-superconformal field theories, using the formalism of Landau-Ginzburg orbifolds. Geometrically, these theories are realized as Calabi-Yau hypersurfaces in weighted projective spaces. This generalization makes it possible to construct the mirror partners of many manifolds for which the mirror was not previously known.
NUMERICAL CONSTRAINTS FOR EMBEDDED PROJECTIVE MANIFOLDS
Besana, Gian Mario
an n- fold X in P2n is related to the number of double points of a generic projection of X from P2n+1. Double point formulas, expressing these constraints in terms of Chern classes of the manifolds and its case of the Laksov-Todd double point formula, [37]. An excellent general reference is due to Kleiman
Towards a double field theory on para-Hermitian manifolds
Vaisman, Izu [Department of Mathematics, University of Haifa, Haifa (Israel)] [Department of Mathematics, University of Haifa, Haifa (Israel)
2013-12-15T23:59:59.000Z
In a previous paper, we have shown that the geometry of double field theory has a natural interpretation on flat para-Kähler manifolds. In this paper, we show that the same geometric constructions can be made on any para-Hermitian manifold. The field is interpreted as a compatible (pseudo-)Riemannian metric. The tangent bundle of the manifold has a natural, metric-compatible bracket that extends the C-bracket of double field theory. In the para-Kähler case, this bracket is equal to the sum of the Courant brackets of the two Lagrangian foliations of the manifold. Then, we define a canonical connection and an action of the field that correspond to similar objects of double field theory. Another section is devoted to the Marsden-Weinstein reduction in double field theory on para-Hermitian manifolds. Finally, we give examples of fields on some well-known para-Hermitian manifolds.
Connections on non-symmetric (generalized) Riemannian manifold and gravity
Ivanov, Stefan
2015-01-01T23:59:59.000Z
Connections with (skew-symmetric) torsion on non-symmetric Riemannian manifold satisfying the Einstein metricity condition (NGT with torsion) are considered. It is shown that an almost Hermitian manifold is an NGT with torsion if and only if it is a Nearly K\\"ahler manifold. In the case of an almost contact metric manifold the NGT with torsion spaces are characterized and a possibly new class of almost contact metric manifolds is extracted. Similar considerations lead to a definition of a particular classes of almost para-Hermitian and almost paracontact metric manifolds. The conditions are given in terms of the corresponding Nijenhuis tensors and the exterior derivative of the skew-symmetric part of the non-symmetric Riemannian metric.
Denis Borisov; Giuseppe Cardone; Tiziana Durante
2015-03-21T23:59:59.000Z
We consider an infinite planar straight strip perforated by small holes along a curve. In such domain, we consider a general second order elliptic operator subject to classical boundary conditions on the holes. Assuming that the perforation is non-periodic and satisfies rather weak assumptions, we describe all possible homogenized problems. Our main result is the norm resolvent convergence of the perturbed operator to a homogenized one in various operator norms and the estimates for the rate of convergence. On the basis of the norm resolvent convergence, we prove the convergence of the spectrum.
Permeability through a perforated domain for the incompressible 2D Euler equations
Virginie Bonnaillie-Noël; Christophe Lacave; Nader Masmoudi
2013-06-17T23:59:59.000Z
We investigate the influence of a perforated domain on the 2D Euler equations. Small inclusions of size $\\varepsilon$ are uniformly distributed on the unit segment or a rectangle, and the fluid fills the exterior. These inclusions are at least separated by a distance $\\varepsilon^\\alpha$ and we prove that for $\\alpha$ small enough (namely, less than 2 in the case of the segment, and less than 1 in the case of the square), the limit behavior of the ideal fluid does not feel the effect of the perforated domain at leading order when $\\varepsilon\\to 0$.
Gorenz, Heather M. (Albuquerque, NM); Brockmann, John E. (Albuquerque, NM); Lucero, Daniel A. (Albuquerque, NM)
2011-09-20T23:59:59.000Z
A powder dispersion method and apparatus comprising an air eductor and a powder dispensing syringe inserted into a suction connection of the air eductor.
Computation of the Flow of a Dual-Stream Jet with External Solid and Perforated Wedge Deflectors for
Papamoschou, Dimitri
Computation of the Flow of a Dual-Stream Jet with External Solid and Perforated Wedge Deflectors used as wedge-shaped fan flow deflectors for reducing jet noise of a supersonic turbofan engine of the external jet plume with solid and perforated deflector flaps, the latter with 50% porosity. Flow
The Yamabe equation on complete manifolds with finite volume
Große, Nadine
2011-01-01T23:59:59.000Z
We prove the existence of a solution of the Yamabe equation on complete manifolds with finite volume and positive Yamabe invariant. In order to circumvent the standard methods on closed manifolds which heavily rely on global (compact) Sobolev embeddings we approximate the solution by eigenfunctions of certain conformal complete metrics. This also gives rise to a new proof of the well-known result for closed manifolds and positive Yamabe invariant.
The genus spectrum of a hyperbolic 3-manifold
McReynolds, D B
2009-01-01T23:59:59.000Z
In this article we study the spectrum of totally geodesic surfaces of a finite volume hyperbolic 3-manifold. We show that for arithmetic hyperbolic 3-manifolds that contain a totally geodesic surface, this spectrum determines the commensurability class. In addition, we show that any finite volume hyperbolic 3-manifold has many pairs of non-isometric finite covers with identical spectra. Forgetting multiplicities, we can also construct pairs where the volume ratio is unbounded.
Marrucci, Lorenzo
SUMMARY Recently published international rankings indicate that the perfor- mance gap between with the research perfor- mance of its universities. Europe invests too little in higher education. It is generally
Hebard, Arthur F.
Trapped Electromagnetic Modes and Scaling in the Transmittance of Perforated Metal Films S. Selcuk that light would not be transmitted by a metal film perforated by a set of holes with size smaller than
Mathematical definition of quantum field theory on a manifold
A. V. Stoyanovsky
2009-11-21T23:59:59.000Z
We give a mathematical definition of quantum field theory on a manifold, and definition of quantization of a classical field theory given by a variational principle.
Engine Air Intake Manifold Having Built In Intercooler
Freese, V, Charles E. (Westland, MI)
2000-09-12T23:59:59.000Z
A turbocharged V type engine can be equipped with an exhaust gas recirculation cooler integrated into the intake manifold, so as to achieve efficiency, cost reductions and space economization improvements. The cooler can take the form of a tube-shell heat exchanger that utilizes a cylindrical chamber in the air intake manifold as the heat exchanger housing. The intake manifold depends into the central space formed by the two banks of cylinders on the V type engine, such that the central space is effectively utilized for containing the manifold and cooler.
Optical manifold for light-emitting diodes
Chaves, Julio C.; Falicoff, Waqidi; Minano, Juan C.; Benitez, Pablo; Parkyn, Jr., William A.; Alvarez, Roberto; Dross, Oliver
2008-06-03T23:59:59.000Z
An optical manifold for efficiently combining a plurality of blue LED outputs to illuminate a phosphor for a single, substantially homogeneous output, in a small, cost-effective package. Embodiments are disclosed that use a single or multiple LEDs and a remote phosphor, and an intermediate wavelength-selective filter arranged so that backscattered photoluminescence is recycled to boost the luminance and flux of the output aperture. A further aperture mask is used to boost phosphor luminance with only modest loss of luminosity. Alternative non-recycling embodiments provide blue and yellow light in collimated beams, either separately or combined into white.
Subsea Manifolds Market | OpenEI Community
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Dispersion strengthened copper
Sheinberg, H.; Meek, T.T.; Blake, R.D.
1990-01-09T23:59:59.000Z
A composition of matter is described which is comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide. A method for making this composition of matter is also described. This invention relates to the art of powder metallurgy and, more particularly, it relates to dispersion strengthened metals.
Random homogenization of p-Laplacian with obstacles in perforated domain
Tang, Lan
2010-01-01T23:59:59.000Z
In this paper,we will study the homogenization of $p$-Laplacian with obstacles in perforated domain, where the holes are periodically distributed and have random size. And we also assume that the $p$-capacity of each hole is stationary ergodic.
Douanla, Hermann Yonta
2011-01-01T23:59:59.000Z
Spectral asymptotics of linear periodic elliptic operators with indefinite (sign-changing) density function is investigated in perforated domains with the two-scale convergence method. The limiting behavior of positive and negative eigencouples depends crucially on whether the average of the weight over the solid part is positive, negative or equal to zero. We prove concise homogenization results in all three cases.
Hermann Yonta Douanla
2012-08-21T23:59:59.000Z
Spectral asymptotics of linear periodic elliptic operators with indefinite (sign-changing) density function is investigated in perforated domains with the two-scale convergence method. The limiting behavior of positive and negative eigencouples depends crucially on whether the average of the weight over the solid part is positive, negative or equal to zero. We prove concise homogenization results in all three cases.
On the effect of perforated plates on the acoustics of annular combustors
Nicoud, Franck
the influence of perforated plates on the acoustic modes in aeronautical gas turbines combustion chambers quantity I. Introduction In order to cut down pollutant emissions, industrial gas turbine combustion and dilution holes [14, 15]. In aeronautical gas turbines, walls of recent combustion chambers are generally
An adiabatic homogeneous model for the flow around a multi-perforated plate
Mendez, Simon
in industrial full-scale computations of gas turbine combustion chambers, where effusion cooling is commonly to the suction side I. Introduction and objectives In gas turbines, the turbine blades and the liner homogeneous model to account for multi-perforated lin- ers in combustion chamber flow simulations is described
A construction of a nonparametric quantum information manifold
Anna Jencova
2005-11-21T23:59:59.000Z
We present a construction of a Banach manifold on the set of faithful normal states of a von Neumann algebra, where the underlying Banach space is a quantum analogue of an Orlicz space. On the manifold, we introduce the exponential and mixture connections as dual pair of affine connections.
Manifold to uniformly distribute a solid-liquid slurry
Kern, Kenneth C. (Lake Hiawatha, NJ)
1983-01-01T23:59:59.000Z
This invention features a manifold that divides a stream of coal particles and liquid into several smaller streams maintaining equal or nearly equal mass compositions. The manifold consists of a horizontal, variable area header having sharp-edged, right-angled take-offs which are oriented on the bottom of the header.
Einstein manifolds with convex boundaries JeanMarc Schlenker \\Lambda
Schlenker, Jean-Marc
Einstein manifolds with convex boundaries JeanÂMarc Schlenker \\Lambda February 2, 1999 Abstract Let (M; @M) be a compact m+1Âmanifold with boundary with an Einstein metric g 0 , with ric g0 = \\Gammamg metric on @M . Then any metric close enough to h 0 is induced on @M by an Einstein metric g with ric g
Einstein manifolds with convex boundaries Jean-Marc Schlenker*
Schlenker, Jean-Marc
Einstein manifolds with convex boundaries Jean Let (M, @M) be a compact m+1-manifold with boundary with an Einstein me* *tric g0, with ricg0 be the induced metric on @M. Then any metric close e* *nough to h0 is induced on @M by an Einstein metric g
General relativity calculus with SageManifolds Eric Gourgoulhon1
Gourgoulhon, Eric
, Poland http://users.camk.edu.pl/bejger/ CoCoNuT Meeting 2013 Observatoire de Paris, Meudon 4 December 2013 ´Eric Gourgoulhon, Michal Bejger (LUTH, CAMK) SageManifolds CoCoNuT Meeting, 4 Dec. 2013 1 / 21 Gourgoulhon, Michal Bejger (LUTH, CAMK) SageManifolds CoCoNuT Meeting, 4 Dec. 2013 2 / 21 #12;An overview
ASYMPTOTIC PROPERTIES OF THE HEAT KERNEL ON CONIC MANIFOLDS
Loya, Paul
ASYMPTOTIC PROPERTIES OF THE HEAT KERNEL ON CONIC MANIFOLDS PAUL LOYA Abstract. We derive Foundation Fellowship. 1 #12; 2 PAUL LOYA Trace expansions of cone operators has a long history stemming from on conic manifolds; see for instance, Callias [5], Cheeger [7], Chou [9], BrË?uning--Seeley [3], Br
NASH-STAMPACCHIA EQUILIBRIUM POINTS ON MANIFOLDS ALEXANDRU KRISTALY
NASH-STAMPACCHIA EQUILIBRIUM POINTS ON MANIFOLDS ALEXANDRU KRIST´ALY Abstract. Motivated by Nash equilibrium problems on 'curved' strategy sets, the concept of Nash-Stampacchia equilibrium points Riemannian manifolds. Characterization, existence, and stability of Nash- Stampacchia equilibria are studied
Dual manifold system and method for fluid transfer
Doktycz, Mitchel J. (Knoxville, TN); Bryan, William Louis (Knoxville, TN); Kress, Reid (Oak Ridge, TN)
2003-05-27T23:59:59.000Z
A dual-manifold assembly is provided for the rapid, parallel transfer of liquid reagents from a microtiter plate to a solid state microelectronic device having biological sensors integrated thereon. The assembly includes aspiration and dispense manifolds connected by a plurality of conduits. In operation, the aspiration manifold is actuated such that the aspiration manifold is seated onto an array of reagent-filled wells of the microtiter plate. The wells are pressurized to force reagent through conduits toward the dispense manifold. A pressure pulse provided by a standard ink-jet printhead ejects nanoliter-to-picoliter droplets of reagent through an array of printhead orifices and onto test sites on the surface of the microelectronic device.
Dual manifold system and method for fluid transfer
Doktycz, Mitchel J.; Bryan, William Louis; Kress, Reid
2003-09-30T23:59:59.000Z
A dual-manifold assembly is provided for the rapid, parallel transfer of liquid reagents from a microtiter plate to a solid state microelectronic device having biological sensors integrated thereon. The assembly includes aspiration and dispense manifolds connected by a plurality of conduits. In operation, the aspiration manifold is actuated such that the aspiration manifold is seated onto an array of reagent-filled wells of the microtiter plate. The wells are pressurized to force reagent through conduits toward the dispense manifold. A pressure pulse provided by a standard ink-jet printhead ejects nanoliter-to-picoliter droplets of reagent through an array of printhead orifices and onto test sites on the surface of the microelectronic device.
Rough Solutions of the Einstein Constraints on Closed Manifolds without Near-CMC Conditions
Holst, Michael; Nagy, Gabriel; Tsogtgerel, Gantumur
2009-01-01T23:59:59.000Z
global) sub- and super-solution constructions for closed manifolds; analogous constructions for compactof compact manifolds with boundary. Lemma 7 (Global super-
Manifold corrections on spinning compact binaries
Zhong Shuangying; Wu Xin [Nanchang University, Nanchang 330031 (China)
2010-05-15T23:59:59.000Z
This paper deals mainly with a discussion of three new manifold correction methods and three existing ones, which can numerically preserve or correct all integrals in the conservative post-Newtonian Hamiltonian formulation of spinning compact binaries. Two of them are listed here. One is a new momentum-position scaling scheme for complete consistency of both the total energy and the magnitude of the total angular momentum, and the other is the Nacozy's approach with least-squares correction of the four integrals including the total energy and the total angular momentum vector. The post-Newtonian contributions, the spin effects, and the classification of orbits play an important role in the effectiveness of these six manifold corrections. They are all nearly equivalent to correct the integrals at the level of the machine epsilon for the pure Kepler problem. Once the third-order post-Newtonian contributions are added to the pure orbital part, three of these corrections have only minor effects on controlling the errors of these integrals. When the spin effects are also included, the effectiveness of the Nacozy's approach becomes further weakened, and even gets useless for the chaotic case. In all cases tested, the new momentum-position scaling scheme always shows the optimal performance. It requires a little but not much expensive additional computational cost when the spin effects exist and several time-saving techniques are used. As an interesting case, the efficiency of the correction to chaotic eccentric orbits is generally better than one to quasicircular regular orbits. Besides this, the corrected fast Lyapunov indicators and Lyapunov exponents of chaotic eccentric orbits are large as compared with the uncorrected counterparts. The amplification is a true expression of the original dynamical behavior. With the aid of both the manifold correction added to a certain low-order integration algorithm as a fast and high-precision device and the fast Lyapunov indicators of two nearby trajectories, phase space scans for chaos in the spinning compact binary system are given.
Dispersion strengthened copper
Sheinberg, Haskell (Los Alamos, NM); Meek, Thomas T. (Knoxville, TN); Blake, Rodger D. (Santa Fe, NM)
1990-01-01T23:59:59.000Z
A composition of matter comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide, and a method for making this composition of matter.
Dispersion strengthened copper
Sheinberg, Haskell (Los Alamos, NM); Meek, Thomas T. (Knoxville, TN); Blake, Rodger D. (Santa Fe, NM)
1989-01-01T23:59:59.000Z
A composition of matter comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide, and a method for making this composition of matter.
Yoder, Graydon L.
1980-01-01T23:59:59.000Z
Dispersed flow consists of small liquid droplets entrained in a flowing vapor. This flow regime can occur in cryogenic equipment, in steam generators, and during nuclear reactor loss of coolant accidents. A theoretical ...
Relativistic fluid mechanics, Kahler manifolds and supersymmetry
T. S. Nyawelo; J. W. van Holten; S. Groot Nibbelink
2003-09-11T23:59:59.000Z
We propose an alternative for the Clebsch decomposition of currents in fluid mechanics, in terms of complex potentials taking values in a Kahler manifold. We reformulate classical relativistic fluid mechanics in terms of these complex potentials and rederive the existence of an infinite set of conserved currents. We perform a canonical analysis to find the explicit form of the algebra of conserved charges. The Kahler-space formulation of the theory has a natural supersymmetric extension in 4-D space-time. It contains a conserved current, but also a number of additional fields complicating the interpretation. Nevertheless, we show that an infinite set of conserved currents emerges in the vacuum sector of the additional fields. This sector can therefore be identified with a regime of supersymmetric fluid mechanics. Explicit expressions for the current and the density are obtained.
Geometric solitons of Hamiltonian flows on manifolds
Song, Chong, E-mail: songchong@xmu.edu.cn [School of Mathematical Sciences, Xiamen University, Xiamen 361005 (China)] [School of Mathematical Sciences, Xiamen University, Xiamen 361005 (China); Sun, Xiaowei, E-mail: sunxw@cufe.edu.cn [School of Applied Mathematics, Central University of Finance and Economics, Beijing 100081 (China)] [School of Applied Mathematics, Central University of Finance and Economics, Beijing 100081 (China); Wang, Youde, E-mail: wyd@math.ac.cn [Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China)] [Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China)
2013-12-15T23:59:59.000Z
It is well-known that the LIE (Locally Induction Equation) admit soliton-type solutions and same soliton solutions arise from different and apparently irrelevant physical models. By comparing the solitons of LIE and Killing magnetic geodesics, we observe that these solitons are essentially decided by two families of isometries of the domain and the target space, respectively. With this insight, we propose the new concept of geometric solitons of Hamiltonian flows on manifolds, such as geometric Schrödinger flows and KdV flows for maps. Moreover, we give several examples of geometric solitons of the Schrödinger flow and geometric KdV flow, including magnetic curves as geometric Schrödinger solitons and explicit geometric KdV solitons on surfaces of revolution.
Andrey Piatnitski; Volodymyr Rybalko
2010-06-03T23:59:59.000Z
The paper deals with homogenization problem for nonlinear elliptic and parabolic equations in a periodically perforated domain, a nonlinear Fourier boundary conditions being imposed on the perforation border. Under the assumptions that the studied differential equation satisfies monotonicity and 2-growth conditions and that the coefficient of the boundary operator is centered at each level set of unknown function, we show that the problem under consideration admits homogenization and derive the effective model.
Piatnitski, Andrey
2010-01-01T23:59:59.000Z
The paper deals with homogenization problem for nonlinear elliptic and parabolic equations in a periodically perforated domain, a nonlinear Fourier boundary conditions being imposed on the perforation border. Under the assumptions that the studied differential equation satisfies monotonicity and 2-growth conditions and that the coefficient of the boundary operator is centered at each level set of unknown function, we show that the problem under consideration admits homogenization and derive the effective model.
Fixed points, stable manifolds, weather regimes, and their predictability
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Deremble, Bruno; D'Andrea, Fabio; Ghil, Michael
2009-10-27T23:59:59.000Z
In a simple, one-layer atmospheric model, we study the links between low-frequency variability and the model’s fixed points in phase space. The model dynamics is characterized by the coexistence of multiple ''weather regimes.'' To investigate the transitions from one regime to another, we focus on the identification of stable manifolds associated with fixed points. We show that these manifolds act as separatrices between regimes. We track each manifold by making use of two local predictability measures arising from the meteorological applications of nonlinear dynamics, namely, ''bred vectors'' and singular vectors. These results are then verified in the framework of ensemblemore »forecasts issued from clouds (ensembles) of initial states. The divergence of the trajectories allows us to establish the connections between zones of low predictability, the geometry of the stable manifolds, and transitions between regimes.« less
Fixed points, stable manifolds, weather regimes, and their predictability
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Deremble, Bruno [Laboratoire de Meteorologie Dynamique (CNRS and IPSL), Paris (France); D'Andrea, Fabio [Laboratoire de Meteorologie Dynamique (CNRS and IPSL), Paris (France); Ghil, Michael [Univ. of California, Los Angeles, CA (United Staes). Atmospheric and Oceanic Sciences and Inst. of Geophysics and Planetary Physics
2009-01-01T23:59:59.000Z
In a simple, one-layer atmospheric model, we study the links between low-frequency variability and the model’s fixed points in phase space. The model dynamics is characterized by the coexistence of multiple ''weather regimes.'' To investigate the transitions from one regime to another, we focus on the identification of stable manifolds associated with fixed points. We show that these manifolds act as separatrices between regimes. We track each manifold by making use of two local predictability measures arising from the meteorological applications of nonlinear dynamics, namely, ''bred vectors'' and singular vectors. These results are then verified in the framework of ensemble forecasts issued from clouds (ensembles) of initial states. The divergence of the trajectories allows us to establish the connections between zones of low predictability, the geometry of the stable manifolds, and transitions between regimes.
Fixed points, stable manifolds, weather regimes, and their predictability
Deremble, Bruno [Laboratoire de Meteorologie Dynamique (CNRS and IPSL), Paris (France); D'Andrea, Fabio [Laboratoire de Meteorologie Dynamique (CNRS and IPSL), Paris (France); Ghil, Michael [Univ. of California, Los Angeles, CA (United Staes). Atmospheric and Oceanic Sciences and Inst. of Geophysics and Planetary Physics
2009-10-27T23:59:59.000Z
In a simple, one-layer atmospheric model, we study the links between low-frequency variability and the model’s fixed points in phase space. The model dynamics is characterized by the coexistence of multiple ''weather regimes.'' To investigate the transitions from one regime to another, we focus on the identification of stable manifolds associated with fixed points. We show that these manifolds act as separatrices between regimes. We track each manifold by making use of two local predictability measures arising from the meteorological applications of nonlinear dynamics, namely, ''bred vectors'' and singular vectors. These results are then verified in the framework of ensemble forecasts issued from clouds (ensembles) of initial states. The divergence of the trajectories allows us to establish the connections between zones of low predictability, the geometry of the stable manifolds, and transitions between regimes.
Jacobi Fields on Statistical Manifolds of Negative Curvature
Carlo Cafaro; S. A. Ali
2007-02-14T23:59:59.000Z
Two entropic dynamical models are considered. The geometric structure of the statistical manifolds underlying these models is studied. It is found that in both cases, the resulting metric manifolds are negatively curved. Moreover, the geodesics on each manifold are described by hyperbolic trajectories. A detailed analysis based on the Jacobi equation for geodesic spread is used to show that the hyperbolicity of the manifolds leads to chaotic exponential instability. A comparison between the two models leads to a relation among statistical curvature, stability of geodesics and relative entropy-like quantities. Finally, the Jacobi vector field intensity and the entropy-like quantity are suggested as possible indicators of chaoticity in the ED models due to their similarity to the conventional chaos indicators based on the Riemannian geometric approach and the Zurek-Paz criterion of linear entropy growth, respectively.
3-MANIFOLDS, TANGLES AND PERSISTENT INVARIANTS JOZEF H. PRZYTYCKI
Silver, Dan
in the last section. We are grateful to J. Scott Carter, Mietek D¸abkowski and Seiichi Kamada for stimu3-MANIFOLDS, TANGLES AND PERSISTENT INVARIANTS J´OZEF H. PRZYTYCKI Department of Mathematics
Classification of Certain Compact Riemannian Manifolds with Harmonic Curvature a...
Derdzinski, Andrzej
Classification of Certain Compact Riemannian Manifolds with Harmonic Curvature a... Derdzinski and University Library provides access to digitized documents strictly for noncommercial educational, research) requires prior written permission from the Goettingen State- and University Library. Each copy of any part
The world problem: on the computability of the topology of 4-manifolds
James R. van Meter
2005-06-03T23:59:59.000Z
Topological classification of the 4-manifolds bridges computation theory and physics. A proof of the undecidability of the homeomorphy problem for 4-manifolds is outlined here in a clarifying way. It is shown that an arbitrary Turing machine with an arbitrary input can be encoded into the topology of a 4-manifold, such that the 4-manifold is homeomorphic to a certain other 4-manifold if and only if the corresponding Turing machine halts on the associated input. Physical implications are briefly discussed.
Protoplanetary disc evolution and dispersal
Owen, James Edward
2011-10-11T23:59:59.000Z
evolution and dispersal time-scales. The main question this thesis attempts to address is: Can photoevaporation provide a dominant dispersal mechanism for the observed population of young stars? Photoevaporation arises from the heating that high energy...
Thermorheological properties of nanostructured dispersions
Gordon, Jeremy B
2007-01-01T23:59:59.000Z
Nanostructured dispersions, which consist of nanometer-sized particles, tubes, sheets, or droplets that are dispersed in liquids, have exhibited substantially higher thermal conductivities over those of the liquids alone. ...
Dispersive analysis of ?/? ? 3?, ??*
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Danilkin, Igor V.; Fernandez Ramirez, Cesar; Guo, Peng; Mathieu, Vincent; Schott, Diane M.; Shi, Meng; Szczepaniak, Adam P.
2015-05-01T23:59:59.000Z
The decays ?/? ? 3? are considered in the dispersive framework that is based on the isobar decomposition and subenergy unitarity. The inelastic contributions are parametrized by the power series in a suitably chosen conformal variable that properly accounts for the analytic properties of the amplitude. The Dalitz plot distributions and integrated decay widths are presented. Our results indicate that the final- state interactions may be sizable. As a further application of the formalism we also compute the electromagnetic transition form factors of ?/? ? ???*.
Nozzle for electric dispersion reactor
Sisson, W.G.; Harris, M.T.; Scott, T.C.; Basaran, O.A.
1998-06-02T23:59:59.000Z
A nozzle for an electric dispersion reactor includes two coaxial cylindrical bodies, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode. 5 figs.
Nozzle for electric dispersion reactor
Sisson, W.G.; Basaran, O.A.; Harris, M.T.
1998-04-14T23:59:59.000Z
A nozzle for an electric dispersion reactor includes two concentric electrodes, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode. 4 figs.
Nozzle for electric dispersion reactor
Sisson, W.G.; Basaran, O.A.; Harris, M.T.
1995-11-07T23:59:59.000Z
A nozzle for an electric dispersion reactor includes two concentric electrodes, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode. 4 figs.
Homogenization of Steklov spectral problems with indefinite density function in perforated domains
Douanla, Hermann Yonta
2011-01-01T23:59:59.000Z
The asymptotic behavior of second order self-adjoint elliptic Steklov eigenvalue problems with periodic rapidly oscillating coefficients and with indefinite (sign-changing) density function is investigated in periodically perforated domains. We prove that the spectrum of this problem is discrete and consists of two sequences, one tending to -{\\infty} and another towards +{\\infty}. The limiting behavior of positive and negative eigencouples depends crucially on whether the average of the weight over the surface of the reference hole is positive, negative or equal to zero. By means of the two-scale convergence method, we prove concise homogenization results in all three cases.
Homogenization of Steklov spectral problems with indefinite density function in perforated domains
Hermann Yonta Douanla
2012-08-21T23:59:59.000Z
The asymptotic behavior of second order self-adjoint elliptic Steklov eigenvalue problems with periodic rapidly oscillating coefficients and with indefinite (sign-changing) density function is investigated in periodically perforated domains. We prove that the spectrum of this problem is discrete and consists of two sequences, one tending to -{\\infty} and another to +{\\infty}. The limiting behavior of positive and negative eigencouples depends crucially on whether the average of the weight over the surface of the reference hole is positive, negative or equal to zero. By means of the two-scale convergence method, we investigate all three cases.
Wei, Zeyong; Fan, Yuancheng; Yu, Xing; Li, Hongqiang
2011-01-01T23:59:59.000Z
This paper theoretically and experimentally presents a first report on broadband enhanced transmission through stacked metallic multi-layers perforated with coaxial annular apertures (CAAs). Different from previous studies on extraordinary transmission that occurs at a single frequency, the enhanced transmission of our system with two or three metallic layers can span a wide frequency range with a bandwidth about 60% of the central frequency. The phenomena arise from the excitation and hybridization of guided resonance modes in CAAs among different layers. Measured transmission spectra are in good agreement with calculations semi-analytically resolved by modal expansion method.
L. A. Falkovsky
2007-08-11T23:59:59.000Z
Taking into account the constraints imposed by the lattice symmetry, the phonon dispersion is calculated for graphene with interactions between the first and second nearest neighbors in the framework of the Born-von Karman model. Analytical expressions are obtained for the out-of-plane (bending) modes determined only by two force constants as well as for the in-plane modes with four force constants. Values of the force constants are found in fitting to elastic constants and Raman frequencies observed in graphite.
First laboratory perforating tests in coal show lower-than-expected penetration
Snider, P.M.; Walton, I.C.; Skinner, T.K.; Atwood, D.C.; Grove, B.M.; Graham, C.
2008-06-15T23:59:59.000Z
Worldwide Coal Bed Methane (CBM) resources are huge, estimated at 3,000 to 9,000 Tcf. The production rate from CBM reservoirs is low, perhaps 50-100 mcf/day. Various completion methods are being evaluated and new technologies are being developed with the aim of increasing production rates. Considering this interest and activity level, little attention has been paid to the CBM completion fundamentals. Perforating is a critical part of this process, especially considering the PRB development migration from single-coal, open-hole completions into multi-zone, cased-hole completions. This paper describes the first known laboratory-testing program to investigate shaped charge penetration in coal targets. We describe mechanical properties of the coals tested, and penetration results for different shaped charges (of different designs), shot at various stress conditions. CT scan and cutaway imaging of the perforation tunnels are also discussed. Tests were conducted under dry and saturated conditions. The preliminary experiments reported here indicate that shaped charge penetration in coal is significantly less than expected, considering the target's density and strength. The authors provide insight into what may be the reasons for these unexpected results and recommend a path forward for shaped charge testing, designs, predictive tools, and how to optimize CBM completions.
Distributed mean curvature on a discrete manifold for Regge calculus
Rory Conboye; Warner A. Miller; Shannon Ray
2015-02-26T23:59:59.000Z
The integrated mean curvature of a simplicial manifold is well understood in both Regge Calculus and Discrete Differential Geometry. However, a well motivated pointwise definition of curvature requires a careful choice of volume over which to uniformly distribute the local integrated curvature. We show that hybrid cells formed using both the simplicial lattice and its circumcentric dual emerge as a remarkably natural structure for the distribution of this local integrated curvature. These hybrid cells form a complete tessellation of the simplicial manifold, contain a geometric orthonormal basis, and are also shown to give a pointwise mean curvature with a natural interpretation as a fractional rate of change of the normal vector.
Self-dual metrics on toric 4-manifolds: extending the Joyce construction
Griffiths, Hugh Norman
2009-01-01T23:59:59.000Z
Toric geometry studies manifolds M2n acted on effectively by a torus of half their dimension, Tn. Joyce shows that for such a 4-manifold sufficient conditions for a conformal class of metrics on the free part of the ...
Schneider, Glenn
on instrument perfor- mance John W. MacKenty, Glenn Schneider*, Sylvia M. Baggett, Dana D. Mitchell, Christine E
ALMOST JET STRUCTURES AND FIRST JET-EXTENSIONS OF FIBRED MANIFOLDS
Pasquero, Stefano
ALMOST JET STRUCTURES AND FIRST JET-EXTENSIONS OF FIBRED MANIFOLDS Paola Morando Dipartimento di conditions for a manifold M to be diffeomorphic to the first jetextension j1(N) of a fibred manifold N O are given in terms of almost jet structures, i.e. pairs (S, A), where S is a suitable type (2, 1) tensor
An implicit trust-region method on Riemannian manifolds§
2007-06-06T23:59:59.000Z
Jun 6, 2007 ... described in terms of optimizing a smooth function on a manifold (e.g., the eigen- value problem .... Use CG recurrences to update residual and search direction. 21: Set rj+1 = rj .... only once and never re-enter it. However, for ...
Geodesic Regression on Riemannian Manifolds P. Thomas Fletcher
Boyer, Edmond
- ing multiple linear regression in Rn . Here we are interested in the relationship between a non that one could choose, and it provides a direct generalization of linear regression to the manifold setting regression model is linear regression, due to its simplicity, ease of interpretation, and ability to model
Energy-Minimizing Splines in Manifolds Michael Hofer
Pottmann, Helmut
Energy-Minimizing Splines in Manifolds Michael Hofer Vienna Univ. of Technology Helmut Pottmann Vienna Univ. of Technology Abstract Variational interpolation in curved geometries has many applica of surfaces. This list is more comprehensive than it looks, because it includes variational motion design
nlin.PS/0201047 Unstable manifolds and Schrodinger dynamics
Schroers, Bernd J.
, United Kingdom January 2002 Abstract The time evolution of several interacting Ginzburg-Landau vortices to the unit circle in C . It therefore has an associated integer winding number or degree, which can of the Ginzburg-Landau energy functional. For two vortices the relevant un- stable manifold is constructed
Geometric Integration: Numerical Solution of Differential Equations on Manifolds
Scheichl, Robert
and the solar system. Conserved quantities of a Hamiltonian system, such as energy, linear and angular momentumGeometric Integration: Numerical Solution of Differential Equations on Manifolds C.J. Budd 1 & A riches. Psalms 104:24 Since their introduction by Sir Isaac Newton, differential equations have played
Clay Mathematics Proceedings Kahler-Ricci flow on complete manifolds
Ni, Lei
Clay Mathematics Proceedings K¨ahler-Ricci flow on complete manifolds Lei Ni Abstract. This is a paper based on author's lectures delivered at the 2005 Clay Mathematics Institute summer school at MSRI The 2005 Clay Mathematics Institute summer school at MSRI focused on Perel- man's work on Ricci flow
Protein clustering on a Grassmann manifold Chendra Hadi Suryanto1
Fukui, Kazuhiro
of the protein. The similarity of two protein structures is then defined by the canonical angles between outperforms the k-means clustering with Gauss Integrals Tuned, which is a state-of- the-art descriptor manifold, Gauss Integrals 1 Introduction Since there are numerous proteins whose functions are yet
university-logo Complete affine 3-manifolds and hyperbolic
Goldman, William
university-logo Complete affine 3-manifolds and hyperbolic surfaces Dedicated to Bill Thurston and hyperbolic surfaces #12;university-logo Three-dimensional affine space forms When can a group G act;university-logo Three-dimensional affine space forms When can a group G act on Euclidean space with quotient
Weldability Of New Ferritic Stainless Steel For Exhaust Manifold Application
Paris-Sud XI, Université de
Weldability Of New Ferritic Stainless Steel For Exhaust Manifold Application Vincent Villaret1-2, a-marie.fortain@airliquide.com, e gilles.fras@iut-nimes.fr, f fabien.januard@airliquide.com Keywords: ferritic stainless steel, efficiency and small size. To achieve such requirements, ferritic stainless steels with high chromium content
FUSION OF HAMILTONIAN LOOP GROUP MANIFOLDS AND COBORDISM
Woodward, Christopher
FUSION OF HAMILTONIAN LOOP GROUP MANIFOLDS AND COBORDISM E. MEINRENKEN AND C. WOODWARD Abstract. We References 32 1. Introduction Let G be a compact, connected, simply connected, simple Lie group and \\Sigma. In a sequel [15] to this paper, we apply our method to compute the coefficients of the fusion ring (Verlinde
Environmental Pollution Air Pollution Dispersion Practical Air Pollution Dispersion
Moncrieff, John B.
Environmental Pollution Air Pollution Dispersion 1 of 5 Practical Air Pollution Dispersion in the lectures how such models can be used to explain observed concentrations of air pollutants in an area to a large extent, downwind air pollution levels on a local or regional scale. The Gaussian Plume Model
Peirce, Anthony
of Bunger et al. (In Press) is consistent with past observations of multiple hydraulic fracture growth from Simultaneous Growth of Multiple Hydraulic Fractures A.P. Peirce, University of British Columbia and A.P. Bunger in horizontal well stimulation is the generation of hydraulic fractures (HFs) from all perforation clusters
Peirce, Anthony
Simultaneous Growth of Multiple Hydraulic Fractures A.P. Peirce, University of British Columbia and A.P. Bunger hurdles in horizontal well stimulation is the generation of hydraulic fractures (HFs) from all perforation shadowing" that refers to suppression of some hydraulic fractures by the compressive stresses exerted
Paris-Sud XI, Université de
on the transformation kinetics of TRIP and dual phase steels has been analyzed by many researchers, for example Al are responsible for the deformation pro cess taking place in TRIP steels during and after the phase transforThermo-mechanical behaviour of TRIP 1000 steel sheets subjected to low velocity perforation
Shultis, J. Kenneth
be realized for doubled or "sand- wiched" devices. Index Terms--Perforated detector, semiconductor neutron de neutron detection by a variety of re- search groups [1][14], all of which have generally used B, Li, Li 66506 USA (e-mail: mc- gregor@ksu.edu). Digital Object Identifier 10.1109/TNS.2006.872639 enter
Nicoud, Franck
and Astronautics #12;I. Introduction In order to cut down pollutant emissions, industrial gas turbine combustion on the prediction of combustion instabilities.5,6 In aeronautical gas turbines, walls of recent combustion chambers aims at showing the influence of perforated plates on the acoustic modes in aeronautical gas turbines
Numerical simulation of high-speed penetration-perforation dynamics in layered armor shields
Ayzenberg-Stepanenko, Mark
2012-01-01T23:59:59.000Z
Penetration models and calculating algorithms are presented, describing the dynamics and fracture of composite armor shields penetrated by high-speed small arms. A shield considered consists of hard (metal or ceramic) facing and multilayered fabric backing. A simple formula is proved for the projectile residual velocity after perforation of a thin facing. A new plastic-flow jet model is proposed for calculating penetration dynamics in the case of a thick facing of ceramic or metal-ceramic FGM materials. By bringing together the developed models into a calculating algorithm, a computer tool is designed enabling simulations of penetration processes in the above-mentioned shields and analysis of optimization problems. Some results of computer simulation are presented. It is revealed in particular that strength proof of pliable backing can be better as compared with more rigid backing. Comparison of calculations and test data shows sufficient applicability of the models and the tool.
Maz'ya, Vladimir; Nieves, Michael
2010-01-01T23:59:59.000Z
We describe a method of asymptotic approximations to solutions of mixed boundary value problems for the Laplacian in a three-dimensional domain with many perforations of arbitrary shape, with the Neumann boundary conditions being prescribed on the surfaces of small voids. The only assumption made on the geometry is that the diameter of a void is assumed to be smaller compared to the distance to the nearest neighbour. The asymptotic approximation, obtained here, involves a linear combination of dipole fields constructed for individual voids, with the coefficients, which are determined by solving a linear algebraic system. We prove the solvability of this system and derive an estimate for its solution. The energy estimate is obtained for the remainder term of the asymptotic approximation.
Swaddiwudhipong, S; Liu, Z S
2012-01-01T23:59:59.000Z
Finite element method (FEM) suffers from a serious mesh distortion problem when used for high velocity impact analyses. The smooth particle hydrodynamics (SPH) method is appropriate for this class of problems involving severe damages but at considerable computational cost. It is beneficial if the latter is adopted only in severely distorted regions and FEM further away. The coupled smooth particle hydrodynamics - finite element method (SFM) has been adopted in a commercial hydrocode LS-DYNA to study the perforation of Weldox 460E steel and AA5083-H116 aluminum plates with varying thicknesses and various projectile nose geometries including blunt, conical and ogival noses. Effects of the SPH domain size and particle density are studied considering the friction effect between the projectile and the target materials. The simulated residual velocities and the ballistic limit velocities from the SFM agree well with the published experimental data. The study shows that SFM is able to emulate the same failure mechan...
Numerical simulation of high-speed penetration-perforation dynamics in layered armor shields
Mark Ayzenberg-Stepanenko; Grigory Osharovich
2012-03-07T23:59:59.000Z
Penetration models and calculating algorithms are presented, describing the dynamics and fracture of composite armor shields penetrated by high-speed small arms. A shield considered consists of hard (metal or ceramic) facing and multilayered fabric backing. A simple formula is proved for the projectile residual velocity after perforation of a thin facing. A new plastic-flow jet model is proposed for calculating penetration dynamics in the case of a thick facing of ceramic or metal-ceramic FGM materials. By bringing together the developed models into a calculating algorithm, a computer tool is designed enabling simulations of penetration processes in the above-mentioned shields and analysis of optimization problems. Some results of computer simulation are presented. It is revealed in particular that strength proof of pliable backing can be better as compared with more rigid backing. Comparison of calculations and test data shows sufficient applicability of the models and the tool.
Vladimir Maz'ya; Alexander Movchan; Michael Nieves
2010-05-24T23:59:59.000Z
We describe a method of asymptotic approximations to solutions of mixed boundary value problems for the Laplacian in a three-dimensional domain with many perforations of arbitrary shape, with the Neumann boundary conditions being prescribed on the surfaces of small voids. The only assumption made on the geometry is that the diameter of a void is assumed to be smaller compared to the distance to the nearest neighbour. The asymptotic approximation, obtained here, involves a linear combination of dipole fields constructed for individual voids, with the coefficients, which are determined by solving a linear algebraic system. We prove the solvability of this system and derive an estimate for its solution. The energy estimate is obtained for the remainder term of the asymptotic approximation.
Fermion dispersion in axion medium
N. V. Mikheev; E. N. Narynskaya
2008-12-02T23:59:59.000Z
The interaction of a fermion with the dense axion medium is investigated for the purpose of finding an axion medium effect on the fermion dispersion. It is shown that axion medium influence on the fermion dispersion under astrophysical conditions is negligible small if the correct Lagrangian of the axion-fermion interaction is used.
Modeling volcanic ash dispersal
None
2011-10-06T23:59:59.000Z
Explosive volcanic eruptions inject into the atmosphere large amounts of volcanic material (ash, blocks and lapilli). Blocks and larger lapilli follow ballistic and non-ballistic trajectories and fall rapidly close to the volcano. In contrast, very fine ashes can remain entrapped in the atmosphere for months to years, and may affect the global climate in the case of large eruptions. Particles having sizes between these two end-members remain airborne from hours to days and can cover wide areas downwind. Such volcanic fallout entails a serious threat to aircraft safety and can create many undesirable effects to the communities located around the volcano. The assessment of volcanic fallout hazard is an important scientific, economic, and political issue, especially in densely populated areas. From a scientific point of view, considerable progress has been made during the last two decades through the use of increasingly powerful computational models and capabilities. Nowadays, models are used to quantify hazard scenarios and/or to give short-term forecasts during emergency situations. This talk will be focused on the main aspects related to modeling volcanic ash dispersal and fallout with application to the well known problem created by the Eyjafjöll volcano in Iceland. Moreover, a short description of the main volcanic monitoring techniques is presented.
Geometrical Interpretation of Electromagnetism in 5-Dimensional Manifold
TaeHun Kim; Hyunbyuk Kim
2015-07-12T23:59:59.000Z
In this paper Kaluza-Klein theory is revisited and its implications are elaborated. We show that electromagnetic 4-potential is a deformation factor of a 5-dimensional (5D) manifold along the fifth (5th) axis. The charge-to-mass ratio has a physical meaning as the ratio of the movement along the direction of the 5th axis to the movement in the 4D space-time. Examinations on the interaction between particles registered by different observers suggest a covariance breaking of the 5th dimension. In order to have a 5D matter which is consistent with the construction of the 5D manifold, a notion of particle-thread is considered. Finally, the field equations which extend the Einstein field equations give the total energy-momentum tensor as a sum of that of matter, electromagnetic field, and the interaction between electric current and electromagnetic field.
Fuel cell stack with internal manifolds for reactant gases
Schnacke, Arthur W. (Schenectady, NY)
1985-01-01T23:59:59.000Z
A fuel cell stack includes a plurality of plate-like fuel cells arranged along an axis generally parallel to cell thickness with electrically conductive separator plates between each pair of cells. A plurality of axial manifolds are provided at opposite sides of the stack in outer marginal portions beyond the edges of electrodes and electrolyte tiles. Sealing rings prevent cross-leakage of oxidant fuel gases through use of pairs of outwardly extending lips from opposite tile surfaces bonded to first and second electrode frames respectively. The frames provide transition between electrode edges and manifold perimeters. The pairs of extension lips are sealingly bonded together through an electrically insulative sealing ring with wedge shaped fastening members.
Fuel cell stack with internal manifolds for reactant gases
Schnacke, A.W.
1983-10-12T23:59:59.000Z
A fuel cell stack includes a plurality of plate-like fuel cells arranged along an axis generally parallel to cell thickness with electrically conductive separator plates between each pair of cells. A plurality of axial manifolds are provided at opposite sides of the stack in outer marginal portions beyond the edges of electrodes and electrolyte tiles. Sealing rings prevent cross-leakage of oxidant fuel gases through use of pairs of outwardly extending lips from opposite tile surfaces bonded to first and second electrode frames respectively. The frames provide transition between electrode edges and manifold perimeters. The pairs of extension lips are sealingly bonded together through an electrically insulative sealing ring with wedge shaped fastening members.
Almost Einstein and Poincare-Einstein manifolds in Riemannian signature
A. Rod Gover
2008-03-25T23:59:59.000Z
An almost Einstein manifold satisfies equations which are a slight weakening of the Einstein equations; Einstein metrics, Poincare-Einstein metrics, and compactifications of certain Ricci-flat asymptotically locally Euclidean structures are special cases. The governing equation is a conformally invariant overdetermined PDE on a function. Away from the zeros of this the almost Einstein structure is Einstein, while the zero set gives a scale singularity set which may be viewed as a conformal infinity for the Einstein metric. In this article we give a classification of the possible scale singularity spaces and derive geometric results which explicitly relate the intrinsic conformal geometry of these to the conformal structure of the ambient almost Einstein manifold. Classes of examples are constructed. A compatible generalisation of the constant scalar curvature condition is also developed. This includes almost Einstein as a special case, and when its curvature is suitably negative, is closely linked to the notion of an asymptotically hyperbolic structure.
Geometrical Interpretation of Electromagnetism in 5-Dimensional Manifold
Kim, TaeHun
2015-01-01T23:59:59.000Z
In this paper Kaluza-Klein theory is revisited and its implications are elaborated. We show that electromagnetic 4-potential is a deformation factor of a 5-dimensional (5D) manifold along the fifth (5th) axis. The charge-to-mass ratio has a physical meaning as the ratio of the movement along the direction of the 5th axis to the movement in the 4D space-time. Examinations on the interaction between particles registered by different observers suggest a covariance breaking of the 5th dimension. In order to have a 5D matter which is consistent with the construction of the 5D manifold, a notion of particle-thread is considered. Finally, the field equations which extend the Einstein field equations give the total energy-momentum tensor as a sum of that of matter, electromagnetic field, and the interaction between electric current and electromagnetic field.
Velocity Dispersions Across Bulge Types
Fabricius, Maximilian; Bender, Ralf; Hopp, Ulrich [University Observatory of the Ludwig-Maximilians University (LMU) (Germany); Max-Planck Institute for Extraterrestrial Physics (MPE) (Germany); Saglia, Roberto; Drory, Niv [Max-Planck Institute for Extraterrestrial Physics (MPE) (Germany); Fisher, David [Department of Astronomy, University of Texas at Austin (United States)
2010-06-08T23:59:59.000Z
We present first results from a long-slit spectroscopic survey of bulge kinematics in local spiral galaxies. Our optical spectra were obtained at the Hobby-Eberly Telescope with the LRS spectrograph and have a velocity resolution of 45 km/s (sigma*), which allows us to resolve the velocity dispersions in the bulge regions of most objects in our sample. We find that the velocity dispersion profiles in morphological classical bulge galaxies are always centrally peaked while the velocity dispersion of morphologically disk-like bulges stays relatively flat towards the center--once strongly barred galaxies are discarded.
Ohbuchi, Ryutarou
printers,... User generated. T i bl 3D h· Trimble 3D warehouse... 3D model retrieval is essential scanners, 3D printers,... User generated. T i bl 3D h· Trimble 3D warehouse... 3D model retrievalRanking on Cross Domain Manifold forRanking on Cross-Domain Manifold for Sketch-based 3D model
Ohbuchi, Ryutarou
printers,... User generated. T i bl 3D h· Trimble 3D warehouse... 3D model retrieval is essentialRanking on Cross Domain Manifold forRanking on Cross-Domain Manifold for Sketch-based 3D model Retrieval Takahiko FuruyaRyutarou Ohbuchi University of Yamanashi #12;IntroductionIntroduction 3D models
Heterogeneous Catalysis on Atomically Dispersed Supported Metals...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Dispersed Supported Metals: CO2 Reduction on Multifunctional Pd Catalysts. Heterogeneous Catalysis on Atomically Dispersed Supported Metals: CO2 Reduction on Multifunctional Pd...
Odd Jacobi manifolds: general theory and applications to generalised Lie algebroids
Andrew James Bruce
2012-06-28T23:59:59.000Z
In this paper we define a Grassmann odd analogue of Jacobi structure on a supermanifold. The basic properties are explored. The construction of odd Jacobi manifolds is then used to reexamine the notion of a Jacobi algebroid. It is shown that Jacobi algebroids can be understood in terms of a kind of curved Q-manifold, which we will refer to as a quasi Q-manifold.
Dispersion-compensated Fresnel lens
Johnson, K.C.
1992-11-03T23:59:59.000Z
A transmission grating is used to reduce chromatic aberration in a Fresnel lens, wherein the lens chromatic dispersion is offset and substantially canceled by the grating's diffraction-induced dispersion. The grating comprises a Fresnel-type pattern of microscopic facets molded directly into the lens surface. The facets would typically have a profile height of around 4[times]10[sup [minus]5] inch and a profile width of at least 10[sup [minus]3] inch. In its primary intended application, the invention would function to improve the optical performance of a Fresnel lens used to concentrate direct sunlight. 10 figs.
Dispersion-compensated fresnel lens
Johnson, Kenneth C. (1215 Brewster Dr., El Cerrito, CA 94530)
1992-01-01T23:59:59.000Z
A transmission grating is used to reduce chromatic aberration in a Fresnel lens, wherein the lens chromatic dispersion is offset and substantially canceled by the grating's diffraction-induced dispersion. The grating comprises a Fresnel-type pattern of microscopic facets molded directly into the lens surface. The facets would typically have a profile height of around 4.multidot.10.sup.-5 inch and a profile width of at least 10.sup.-3 inch. In its primary intended application, the invention would function to improve the optical performance of a Fresnel lens used to concentrate direct sunlight.
Tensor calculus with open-source software: the SageManifolds project
Eric Gourgoulhon; Michal Bejger; Marco Mancini
2014-12-21T23:59:59.000Z
The SageManifolds project aims at extending the mathematics software system Sage towards differential geometry and tensor calculus. Like Sage, SageManifolds is free, open-source and is based on the Python programming language. We discuss here some details of the implementation, which relies on Sage's parent/element framework, and present a concrete example of use.
Hamilton-Jacobi Equations on a Manifold and Applications to Grid Generation or Re nement.
Hamilton-Jacobi Equations on a Manifold and Applications to Grid Generation or Re#28;nement. Ph Hamilton-Jacobi equations on a manifold, typically on the graph of some previously computed function z method. Keywords: Hamilton-Jacobi equations, viscosity solutions, level set method, adaptative meshes
EXPLICIT, IMPLICIT AND PARAMETRIC INVARIANT MANIFOLDS FOR MODEL REDUCTION IN CHEMICAL KINETICS
), Russia e-mail: hsablem@yahoo.com #12;Abstract Many systems studied in chemical kinetics can be posedEXPLICIT, IMPLICIT AND PARAMETRIC INVARIANT MANIFOLDS FOR MODEL REDUCTION IN CHEMICAL KINETICS and parametric invariant manifolds for model reduction in chemical kinetics V. Sobolev and E. Shchepakina
THE CO-STABILITY MANIFOLD OF A TRIANGULATED CATEGORY PETER JRGENSEN AND DAVID PAUKSZTELLO
JÃ¸rgensen, Peter
THE CO-STABILITY MANIFOLD OF A TRIANGULATED CATEGORY PETER JÃ?RGENSEN AND DAVID PAUKSZTELLO Abstract co-stability conditions as a `continuous' generalisation of co-t-structures. Our main result is that the set of nice co-stability conditions on a triangulated category is a manifold. In particular, we show
Determination of dispersivities from a natural-gradient dispersion test
Hoover, Caroline Marie
1985-01-01T23:59:59.000Z
Model DESCRIPTION OF THE NATURAL-GRADIENT DISPERSION TEST. Site Geology. Methodology Summary of Results. APPLICATION OF METHODS. Ideal Pl ume Study. Characterization of the Iterative Diagrams. . . Sensitivity Analyses. Field Tracer Study... with contaminant hydrogeology. Cherry et al. (1975) defines contaminant hydrogeology as the application of hydrogeological and geochemical theory and practice to the protection of aquifers and surface waters from contamination, and to the design and monitoring...
Phonon dispersion of graphene revisited
Sahoo, Rasmita, E-mail: sahoorasmita@yahoo.com; Mishra, Rashmi Ranjan [Birla Institute of Technology and Science, Department of Physics (India)
2012-05-15T23:59:59.000Z
The phonon dispersion of graphene is derived by using a simple mass spring model and considering up to the first, second, third, and fourth nearest-neighbor interactions. The results obtained from different nearest-neighbor interactions are compared and it is shown that the k{sup 2} dependence for the out-of-plane transverse acoustic mode obtained in other sophisticated methods as well as experiment occurs only after including the fourth nearest-neighbor interaction.
Shear dispersion in dense granular flows
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Christov, Ivan C.; Stone, Howard A.
2014-04-18T23:59:59.000Z
We formulate and solve a model problem of dispersion of dense granular materials in rapid shear flow down an incline. The effective dispersivity of the depth-averaged concentration of the dispersing powder is shown to vary as the Péclet number squared, as in classical Taylor–Aris dispersion of molecular solutes. An extension to generic shear profiles is presented, and possible applications to industrial and geological granular flows are noted.
Dispersion enhanced metal/zeolite catalysts
Sachtler, W.M.H.; Tzou, M.S.; Jiang, H.J.
1987-03-31T23:59:59.000Z
Dispersion stabilized zeolite supported metal catalysts are provided as bimetallic catalyst combinations. The catalyst metal is in a reduced zero valent form while the dispersion stabilizer metal is in an unreduced ionic form. Representative catalysts are prepared from platinum or nickel as the catalyst metal and iron or chromium dispersion stabilizer.
Gravitational dispersion in a torsional wave machine
Rafael de la Madrid; Alejandro Gonzalez; George Irwin
2014-09-01T23:59:59.000Z
We demonstrate that mechanical waves traveling in a torsional, mechanical wave machine exhibit dispersion due to gravity and the discreteness of the medium. We also show that although the dispersion due to discreteness is negligible, the dispersion due to gravity can be easily measured, and can be shown to disappear in a zero-gravity environment.
Toric data and Killing forms on homogeneous Sasaki-Einstein manifold $T^{1,1}$
Vladimir Slesar; Mihai Visinescu; Gabriel Eduard Vilcu
2015-03-02T23:59:59.000Z
Throughout this paper we investigate the complex structure of the conifold $C(T^{1,1})$ basically making use of the interplay between symplectic and complex approaches of the K\\"{a}hler toric manifolds. The description of the Calabi-Yau manifold $C(T^{1,1})$ using toric data allows us to write explicitly the complex coordinates and apply standard methods for extracting special Killing forms on the base manifold. As an outcome, we obtain the complete set of special Killing forms on the five-dimensional Sasaki-Einstein space $T^{1,1}$.
High-Dimensional Data Fusion via Joint Manifold Learning Mark A. Davenport,s
that acquire large amounts of very high-dimensional data. To cope with such a data deluge, manifold models number of vantage points and using multiple modalities. This can lead to a veritable data deluge, fueling
. One way to cope with such a data deluge is to develop low-dimensional data models. Manifold models points and using multiple modalities. This can lead to a veritable data deluge, fueling the need
Manifold and method of batch measurement of Hg-196 concentration using a mass spectrometer
Grossman, M.W.; Evans, R.
1991-11-26T23:59:59.000Z
A sample manifold and method of its use has been developed so that milligram quantities of mercury can be analyzed mass spectroscopically to determine the [sup 196]Hg concentration to less than 0.02 atomic percent. Using natural mercury as a standard, accuracy of [+-]0.002 atomic percent can be obtained. The mass spectrometer preferably used is a commercially available GC/MS manufactured by Hewlett Packard. A novel sample manifold is contained within an oven allowing flow rate control of Hg into the MS. Another part of the manifold connects to an auxiliary pumping system which facilitates rapid clean up of residual Hg in the manifold. Sample cycle time is about 1 hour. 8 figures.
Manifold and method of batch measurement of Hg-196 concentration using a mass spectrometer
Grossman, Mark W. (Belmont, MA); Evans, Roger (N. Hampton, NH)
1991-01-01T23:59:59.000Z
A sample manifold and method of its use has been developed so that milligram quantities of mercury can be analyzed mass spectroscopically to determine the .sup.196 Hg concentration to less than 0.02 atomic percent. Using natural mercury as a standard, accuracy of .+-.0.002 atomic percent can be obtained. The mass spectrometer preferably used is a commercially available GC/MS manufactured by Hewlett Packard. A novel sample manifold is contained within an oven allowing flow rate control of Hg into the MS. Another part of the manifold connects to an auxiliary pumping system which facilitates rapid clean up of residual Hg in the manifold. Sample cycle time is about 1 hour.
Asymptotic behavior of complete Ricci-flat metrics on open manifolds
Santoro, Bianca
2006-01-01T23:59:59.000Z
In this thesis, we describe the asymptotic behavior of complete Ricci-flat Kihler metrics on open manifolds that can be compactified by adding a smooth, ample divisor. This result provides an answer to a question addressed ...
Mechanical Systems on an almost Kähler model of a Finsler Manifold
Mehmet Tekkoyun; O?uzhan Çelik
2012-11-06T23:59:59.000Z
In this study, we present a new analogue of Euler-Lagrange and Hamilton equations on an almost K\\"ahler model of a Finsler manifold. Also, we give some corollories about the related mechanical systems and equations.
Characterization and parameterization of the singular manifold of a simple 6-6 Stewart platform
T. Charters; P. Freitas
2008-11-07T23:59:59.000Z
This paper presents a study of the characterization of the singular manifold of the six-degree-of-freedom parallel manipulator commonly known as the Stewart platform. We consider a platform with base vertices in a circle and for which the bottom and top plates are related by a rotation and a contraction. It is shown that in this case the platform is always in a singular configuration and that the singular manifold can be parameterized by a scalar parameter.
Wagner, Anthony
-amino-5-phosphonovaleric acid (APV) infusions, whereas lateral perforant path plasticity can be attenuated by naloxone infusions. The present experiment was designed to evaluate the role of each entorhinal) changes in the overall configuration of environmental stimuli. Dorsal dentate gyrus infusions of either
Superization of Homogeneous Spin Manifolds and Geometry of Homogeneous Supermanifolds
Andrea Santi
2009-05-24T23:59:59.000Z
Let M_0=G_0/H be a (pseudo)-Riemannian homogeneous spin manifold, with reductive decomposition g_0=h+m and let S(M_0) be the spin bundle defined by the spin representation Ad:H->\\GL_R(S) of the stabilizer H. This article studies the superizations of M_0, i.e. its extensions to a homogeneous supermanifold M=G/H whose sheaf of superfunctions is isomorphic to Lambda(S^*(M_0)). Here G is the Lie supergroup associated with a certain extension of the Lie algebra of symmetry g_0 to an algebra of supersymmetry g=g_0+g_1=g_0+S via the Kostant-Koszul construction. Each algebra of supersymmetry naturally determines a flat connection nabla^{S} in the spin bundle S(M_0). Killing vectors together with generalized Killing spinors (i.e. nabla^{S}-parallel spinors) are interpreted as the values of appropriate geometric symmetries of M, namely even and odd Killing fields. An explicit formula for the Killing representation of the algebra of supersymmetry is obtained, generalizing some results of Koszul. The generalized spin connection nabla^{S} defines a superconnection on M, via the super-version of a theorem of Wang.
Polyfunctional dispersants for controlling viscosity of phyllosilicates
Chaiko, David J.
2006-07-25T23:59:59.000Z
This invention provides phyllosilicates and polyfunctional dispersants which can be manipulated to selectively control the viscosity of phyllosilicate slurries. The polyfunctional dispersants used in the present invention, which include at least three functional groups, increase the dispersion and exfoliation of phyllosilicates in polymers and, when used in conjunction with phyllosilicate slurries, significantly reduce the viscosity of slurries having high concentrations of phyllosilicates. The functional groups of the polyfunctional dispersants are capable of associating with multivalent metal cations and low molecular weight organic polymers, which can be manipulated to substantially increase or decrease the viscosity of the slurry in a concentration dependent manner. The polyfunctional dispersants of the present invention can also impart desirable properties on the phyllosilicate dispersions including corrosion inhibition and enhanced exfoliation of the phyllosilicate platelets.
Methods for dispersing hydrocarbons using autoclaved bacteria
Tyndall, R.L.
1996-11-26T23:59:59.000Z
A method of dispersing a hydrocarbon includes the following steps: providing a bacterium selected from the following group: ATCC 85527, ATCC 75529, and ATCC 55638, a mutant of any one of these bacteria possessing all the identifying characteristics of any one of these bacteria, and mixtures; autoclaving the bacterium to derive a dispersant solution; and contacting the dispersant solution with a hydrocarbon to disperse the hydrocarbon. Moreover, a method for preparing a dispersant solution includes the following steps: providing a bacterium selected from the following group: ATCC 75527, ATCC 75529, and ATCC 55638, a mutant of any one of these bacteria possessing all the identifying characteristics of any one of these bacteria, and mixtures; and autoclaving the bacterium to derive a dispersant solution.
Kirby, James T.
Dispersive tsunami waves in the ocean: Model equations and sensitivity to dispersion and Coriolis online 19 December 2012 Keywords: Boussinesq wave model Tsunami Dispersive effect Coriolis effect a bKutta scheme in time. In the context of tsunami generation and propagation over trans-oceanic distances
Method of dispersing a hydrocarbon using bacteria
Tyndall, R.L.
1996-09-24T23:59:59.000Z
A new protozoan derived microbial consortia and method for their isolation are provided. The isolated consortia and bacteria are useful for treating wastes such as trichloroethylene and trinitrotoluene. The isolated consortia, bacteria, and dispersants are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.
Method of dispersing a hydrocarbon using bacteria
Tyndall, Richard L. (Clinton, TN)
1996-01-01T23:59:59.000Z
New protozoan derived microbial consortia and method for their isolation are provided. Consortia and bacteria isolated therefrom are useful for treating wastes such as trichloroethylene and trinitrotoluene. Consortia, bacteria isolated therefrom, and dispersants isolated therefrom are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.
Axion-medium effect on fermion dispersion
Mikheev, N. V., E-mail: mikheev@uniyar.ac.ru; Narynskaya, E. N., E-mail: elenan@uniyar.ac.r [Yaroslavl State University (Russian Federation)
2008-08-15T23:59:59.000Z
The interaction of fermions with a dense axion medium is considered with the aim of studying the effect of the axionmediumon fermion dispersion. It is shown that, if use is made of a correct Lagrangian for axion-fermion interaction, the effect of a dense axion medium on fermion dispersion is negligible under real astrophysical conditions.
Broadband dispersion extraction using simultaneous sparse penalization
Saligrama, Venkatesh
the borehole and thus dispersion analysis is of considerable interest to the geophysical and oilfield services community. A brief survey of borehole acoustic waves and their use in mechanical characterization is a function of frequency. This function characterizes the mode and is referred to as a dispersion curve
A multifaceted approach to applying dispersants
Crain, O.L.
1982-10-01T23:59:59.000Z
A comprehensive oil spill response plan has been developed partially to deal with accidental discharges of oil into the Arabian Gulf. The spill response capabilities of contractor companies in the area are fairly limited. The response plan relies on chemical agents and recovery as cleanup tools. The key to effective response is a rapid response and deployment of cleanup equipment. Initially, marine vessels equipped with portable dispersant spray booms patterned after the Warren Springs equipment were used. To improve existing oil spill response, an extensive modernization of dispersant deployment equipment has been developed. The areas of modernization include upgrading the marine vessel equipment, dedicating boats and vessels of opportunity for dispersant application, using helicopters for spill response, using large fixed-wing aircraft for spill response, and establishing dispersant and refueling stockpiles. This paper discusses the use of dispersants in response to an oil spill. It is intended not as a scientific paper but as a paper on a local response capability.
Dispersion relations in noncommutative theories
Mariz, Tiago; Nascimento, J. R.; Rivelles, Victor O. [Departamento de Fisica, Universidade Federal da Paraiba, 58051-970, Joao Pessoa, PB (Brazil); Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05315-970, Sao Paulo, SP (Brazil)
2007-01-15T23:59:59.000Z
We present a detailed study of plane waves in noncommutative abelian gauge theories. The dispersion relation is deformed from its usual form whenever a constant background electromagnetic field is present and is similar to that of an anisotropic medium with no Faraday rotation nor birefringence. When the noncommutativity is induced by the Moyal product we find that for some values of the background magnetic field no plane waves are allowed when time is noncommutative. In the Seiberg-Witten context no restriction is found. We also derive the energy-momentum tensor in the Seiberg-Witten case. We show that the generalized Poynting vector obtained from the energy-momentum tensor, the group velocity and the wave vector all point in different directions. In the absence of a constant electromagnetic background we find that the superposition of plane waves is allowed in the Moyal case if the momenta are parallel or satisfy a sort of quantization condition. We also discuss the relation between the solutions found in the Seiberg-Witten and Moyal cases showing that they are not equivalent.
Weyl Tensor Classification in Four-dimensional Manifolds of All Signatures
Carlos Batista
2013-02-07T23:59:59.000Z
It is well known that the classification of the Weyl tensor in Lorentzian manifolds of dimension four, the so called Petrov classification, was a great tool to the development of general relativity. Using the bivector approach it is shown in this article a classification for the Weyl tensor in all four-dimensional manifolds, including all signatures and the complex case, in an unified and simple way. The important Petrov classification then emerges just as a particular case in this scheme. The boost weight classification is also extended here to all signatures as well to complex manifolds. For the Weyl tensor in four dimensions it is established that this last approach produces a classification equivalent to the one generated by the bivector method.
Zuo-Bing Wu
2008-03-17T23:59:59.000Z
In this paper, a method to construct topological template in terms of symbolic dynamics for the diamagnetic Kepler problem is proposed. To confirm the topological template, rotation numbers of invariant manifolds around unstable periodic orbits in a phase space are taken as an object of comparison. The rotation numbers are determined from the definition and connected with symbolic sequences encoding the periodic orbits in a reduced Poincar\\'e section. Only symbolic codes with inverse ordering in the forward mapping can contribute to the rotation of invariant manifolds around the periodic orbits. By using symbolic ordering, the reduced Poincar\\'e section is constricted along stable manifolds and a topological template, which preserves the ordering of forward sequences and can be used to extract the rotation numbers, is established. The rotation numbers computed from the topological template are the same as those computed from their original definition.
Natural star-products on symplectic manifolds and related quantum mechanical operators
B?aszak, Maciej, E-mail: blaszakm@amu.edu.pl; Doma?ski, Ziemowit, E-mail: ziemowit@amu.edu.pl
2014-05-15T23:59:59.000Z
In this paper is considered a problem of defining natural star-products on symplectic manifolds, admissible for quantization of classical Hamiltonian systems. First, a construction of a star-product on a cotangent bundle to an Euclidean configuration space is given with the use of a sequence of pair-wise commuting vector fields. The connection with a covariant representation of such a star-product is also presented. Then, an extension of the construction to symplectic manifolds over flat and non-flat pseudo-Riemannian configuration spaces is discussed. Finally, a coordinate free construction of related quantum mechanical operators from Hilbert space over respective configuration space is presented. -- Highlights: •Invariant representations of natural star-products on symplectic manifolds are considered. •Star-products induced by flat and non-flat connections are investigated. •Operator representations in Hilbert space of considered star-algebras are constructed.
IS-321-312-001 TEP-to-HTEP manifold interface sheet
Willms, R Scott [Los Alamos National Laboratory; Carlson, Bryan J [Los Alamos National Laboratory; Coons, James E [Los Alamos National Laboratory; Kubic, William L [Los Alamos National Laboratory
2008-01-01T23:59:59.000Z
The Tokamak Exhaust Processing System (TEP) receives hydrogen-like and air-like gas streams from the High Tritium Exhaust Processing (HTEP) manifold. Gases from the torus roughing pump are pumped into the HTEP manifold before entering TEP. This interface sheet describes the TEP-HTEP material stream interface, both the physical elements that make up the interface as well as the gas streams that will flow through the interface. The functions of this interface are to: Provide a physical connection for the transport of hydrogen-like and air-like gases from the HTEP manifold to TEP. Provide seals to prevent the unncessary release of tritium to the surrounding environment. Provide valves that can be actuated to stop or prevent the flow of gas into TEP.
McGregor, Douglas S. (Riley, KS); Shultis, John K. (Manhattan, KS); Rice, Blake B. (Manhattan, KS); McNeil, Walter J. (Winnfield, KS); Solomon, Clell J. (Wichita, KS); Patterson, Eric L. (Manhattan, KS); Bellinger, Steven L. (Manhattan, KS)
2010-12-21T23:59:59.000Z
Non-streaming high-efficiency perforated semiconductor neutron detectors, method of making same and measuring wands and detector modules utilizing same are disclosed. The detectors have improved mechanical structure, flattened angular detector responses, and reduced leakage current. A plurality of such detectors can be assembled into imaging arrays, and can be used for neutron radiography, remote neutron sensing, cold neutron imaging, SNM monitoring, and various other applications.
Electromagnetic Media with no Dispersion Equation
Ismo V. Lindell; Alberto Favaro
2013-03-25T23:59:59.000Z
It has been known through some examples that parameters of an electromagnetic medium can be so defined that there is no dispersion equation (Fresnel equation) to restrict the choice of the wave vector of a plane wave in such a medium, i.e., that the dispersion equation is satisfied identically for any wave vector. In the present paper, a more systematic study to define classes of media with no dispersion equation is attempted. The analysis makes use of coordinate-free four-dimensional formalism in terms of multivectors, multiforms and dyadics.
Kahler Potential for M-theory on a G_2 Manifold
Andre Lukas; Stephen Morris
2003-11-21T23:59:59.000Z
We compute the moduli Kahler potential for M-theory on a compact manifold of G_2 holonomy in a large radius approximation. Our method relies on an explicit G_2 structure with small torsion, its periods and the calculation of the approximate volume of the manifold. As a verification of our result, some of the components of the Kahler metric are computed directly by integration over harmonic forms. We also discuss the modification of our result in the presence of co-dimension four singularities and derive the gauge-kinetic functions for the massless gauge fields that arise in this case.
A new approach for magnetic curves in 3D Riemannian manifolds
Bozkurt, Zehra, E-mail: zbozkurt@ankara.edu.tr; Gök, Ismail, E-mail: igok@science.ankara.edu.tr; Yayl?, Yusuf, E-mail: yayli@science.ankara.edu.tr; Ekmekci, F. Nejat, E-mail: ekmekci@science.ankara.edu.tr [Department of Mathematics, Faculty of Science, University of Ankara, Ankara (Turkey)
2014-05-15T23:59:59.000Z
A magnetic field is defined by the property that its divergence is zero in a three-dimensional oriented Riemannian manifold. Each magnetic field generates a magnetic flow whose trajectories are curves called as magnetic curves. In this paper, we give a new variational approach to study the magnetic flow associated with the Killing magnetic field in a three-dimensional oriented Riemann manifold, (M{sup 3}, g). And then, we investigate the trajectories of the magnetic fields called as N-magnetic and B-magnetic curves.
An integral manifold approach to reduced order dynamic modeling of synchronous machines
Sauer, P.W.; Ahmed-Zaid, S.; Kokotovic, P.V.
1988-02-01T23:59:59.000Z
The concept of integral manifolds is used to systematically create improved reduced order models of synchronous machines. The approach is illustrated through a detailed example of a single machine connected to an infinite bus. The example shows the advantages of the manifold approach and also clarifies several issues about reduced order models of synchronous machines. The basic objective of the method is to include the effects of more complex models without actually including the additional differential equations. This is illustrated by including the effects of stator transients and damper windings on the swing equation without including the differential equations.
Utah, University of
of the population. We evaluate the proposed method on the OASIS and ADNI brain databases of head MR images in twoManifold modeling for brain population analysis Samuel Gerber *, Tolga Tasdizen, P. Thomas Fletcher Brain MRI Manifold learning Computer aided clinical diagnosis a b s t r a c t This paper describes
Wisconsin at Madison, University of
Multivariate General Linear Models (MGLM) on Riemannian Manifolds with Applications to Statistical range of such methods by deriv- ing schemes for multivariate multiple linear regression -- a manifold ] , ^ = ¯y - ^¯x. (2) If x and y are multivariates, one can easily replace the mul- tiplication and division
Needell, Deanna
CS Applications CS Math MR Applications MR Math MR Theory Proof Bridging Matrix Recovery Gaps using #12;CS Applications CS Math MR Applications MR Math MR Theory Proof Outline Compressed Sensing (CS manifold theory Deanna Needell Bridging Matrix Recovery Gaps using Manifolds #12;CS Applications CS Math MR
Photon statistics dispersion in excitonic composites
G. Ya. Slepyan; S. A. Maksimenko
2006-05-22T23:59:59.000Z
Linear media are predicted to exist whose relative permiability is an operator in the space of quantum states of light. Such media are characterized by a photon statistics--dependent refractive index. This indicates a new type of optical dispersion -- the photon statistics dispersion. Interaction of quantum light with such media modifies the photon number distribution and, in particular, the degree of coherence of light. An excitonic composite -- a collection of noninteracting quantum dots -- is considered as a realization of the medium with the photon statistics dispersion. Expressions are derived for generalized plane waves in an excitonic composite and input--output relations for a planar layer of the material. Transformation rules for different photon initial states are analyzed. Utilization of the photon statistics dispersion in potential quantum--optical devices is discussed.
Dense gas dispersion modeling for aqueous releases
Lara, Armando
1999-01-01T23:59:59.000Z
concern since they disperse at ground level. Toxic or combustible materials with boiling points below ambient temperature, such as chlorine and ammonia, are usually stored or transported as a saturated liquid. A release from such a system is likely...
Atmospheric dispersion in mountain valleys and basins
Allwine, K.J.
1992-01-01T23:59:59.000Z
The primary goal of the research is to further characterize and understand dispersion in valley and basin atmospheres. A secondary, and related goal, is to identify and understand the dominant physical processes governing this dispersion. This has been accomplished through a review of the current literature, and analyses of recently collected data from two field experiments. This work should contribute to an improved understanding of material transport in the atmospheric boundary layer. It was found that dispersion in a freely draining valley (Brush Creek valley, CO) atmosphere is much greater than in an enclosed basin (Roanoke, VA) atmosphere primarily because of the greater wind speeds moving past the release point and the greater turbulence levels. The development of a cold air pool in the Roanoke basin is the dominant process governing nighttime dispersion in the basin, while the nighttime dispersion in the Brush Creek valley is dominated by turbulent diffusion and plume confinement between the valley sidewalls. The interaction between valley flows and above ridgetops flows is investigated. A ventilation rate'' of material transport between the valley and above ridgetop flows is determined. This is important in regional air pollution modeling and global climate modeling. A simple model of dispersion in valleys, applicable through a diurnal cycle, is proposed.
Atmospheric dispersion in mountain valleys and basins
Allwine, K.J.
1992-01-01T23:59:59.000Z
The primary goal of the research is to further characterize and understand dispersion in valley and basin atmospheres. A secondary, and related goal, is to identify and understand the dominant physical processes governing this dispersion. This has been accomplished through a review of the current literature, and analyses of recently collected data from two field experiments. This work should contribute to an improved understanding of material transport in the atmospheric boundary layer. It was found that dispersion in a freely draining valley (Brush Creek valley, CO) atmosphere is much greater than in an enclosed basin (Roanoke, VA) atmosphere primarily because of the greater wind speeds moving past the release point and the greater turbulence levels. The development of a cold air pool in the Roanoke basin is the dominant process governing nighttime dispersion in the basin, while the nighttime dispersion in the Brush Creek valley is dominated by turbulent diffusion and plume confinement between the valley sidewalls. The interaction between valley flows and above ridgetops flows is investigated. A ``ventilation rate`` of material transport between the valley and above ridgetop flows is determined. This is important in regional air pollution modeling and global climate modeling. A simple model of dispersion in valleys, applicable through a diurnal cycle, is proposed.
ESTIMATION OF EXHAUST MANIFOLD PRESSURE IN TURBOCHARGED GASOLINE ENGINES WITH VARIABLE VALVE TIMING
Grizzle, Jessy W.
ESTIMATION OF EXHAUST MANIFOLD PRESSURE IN TURBOCHARGED GASOLINE ENGINES WITH VARIABLE VALVE TIMING in turbocharged gasoline engines with variable valve timing requires knowledge of exhaust mani- fold pressure, Pe control systems for gasoline engines rely heavily on feedforward air-fuel ratio (A/F) control to meet
Minimal Riesz energy point configurations for rectifiable d-dimensional manifolds
Hardin, Doug
, these results are new. Key words: Minimal discrete Riesz energy, Best-packing, Hausdorff measure, Rectifiable best-packing, mini- mization of energy (e.g., Coulomb potentials), spherical t-designs (cubatureMinimal Riesz energy point configurations for rectifiable d-dimensional manifolds D.P. Hardin
Integrability of D1-brane on Group Manifold with Mixed Three Form Flux
Kluson, J
2015-01-01T23:59:59.000Z
We consider D1-brane as a natural probe of the group manifold with mixed three form fluxes. We determine Lax connection for given theory. Then we switch to the canonical analysis and calculate the Poisson brackets between spatial components of Lax connections and we argue for integrability of given theory.
Paris-Sud XI, Université de
Reduction, Centre Manifold, Robust Analysis, Uncertainty Propagation, Polynomial chaos, Non-intrusive to compute the deterministic components called stochastic modes in an intrusive and a non intrusive manner while random components are concentrated in the polynomial basis used. Non intrusive procedures
Invariant Manifolds for the Station Keeping of Solar Sails Ariadna Farres, AJ
Boyer, Edmond
Invariant Manifolds for the Station Keeping of Solar Sails Ariadna Farr´es, AJ Universitat de 2 / 45 inria-00585612,version1-14Apr2011 #12;Background What is a Solar Sail ? Solar Sails are a new concept of spacecraft propulsion that takes ad- vantage of the Solar radiation pressure to propel
Side branch absorber for exhaust manifold of two-stroke internal combustion engine
Harris, Ralph E. (San Antonio, TX); Broerman, III, Eugene L. (San Antonio, TX); Bourn, Gary D. (Laramie, WY)
2011-01-11T23:59:59.000Z
A method of improving scavenging operation of a two-stroke internal combustion engine. The exhaust pressure of the engine is analyzed to determine if there is a pulsation frequency. Acoustic modeling is used to design an absorber. An appropriately designed side branch absorber may be attached to the exhaust manifold.
Manifold Assembly for the Convenient Polymerization of Ethylene Oxide and Butadiene
Notes Manifold Assembly for the Convenient Polymerization of Ethylene Oxide and Butadiene Gre,3-butadiene (BD) are two examples of gaseous monomers at room temperature. Typically, these two gaseous,3-butadiene and ethylene oxide requires great care as they boil at -4.4 and 10.7 °C, respecti
Pose Estimation via Gauss-Newton-on-manifold Pei Yean Lee and John B. Moore
Moore, John Barratt
on the smooth manifold of rotation matrices, namely the special orthogonal matrices SO3, depicted as the surface of a cone in Fig. 1. Also, in Fig. 1, the feasible domain is depicted as the intersection SO3 K. The cost
Computing Lyapunov exponents on a Stiefel manifold by Thomas J. Bridges and Sebastian Reich
Reich, Sebastian
Computing Lyapunov exponents on a Stiefel manifold by Thomas J. Bridges and Sebastian Reich The problem of numerical computation of a few Lyapunov exponents of #12;nite-dimensional dynamical systems computes one, many or all Lyapunov exponents of a continuous dynamical system by time integration, discrete
university-logo Two papers which changed my life: Milnor's seminal work on flat manifolds
Goldman, William
university-logo Two papers which changed my life: Milnor's seminal work on flat manifolds Two Banff International Research Station February 24, 2011 #12;university-logo Two papers which changed my of Euclidean 3-space by free groups of affine transformations. #12;university-logo Two papers which changed my
Manifold-based starting point generation and its application to distillation
Neumaier, Arnold
Manifold-based starting point generation and its application to distillation Ali Baharev*, Ferenc-states in homogeneous azeotropic distillation . . . . . . . . . . 11 5.2 Multiple steady-states in ideal two-product distillation . . . . . . . . . . . . . . 11 6 Conclusion 13 A Ordering sparse matrices 14 A.1 Ordering to block
ANALYTIC EQUIVALENCE OF NORMAL CROSSING FUNCTIONS ON A REAL ANALYTIC MANIFOLD
Paris-Sud XI, Université de
ANALYTIC EQUIVALENCE OF NORMAL CROSSING FUNCTIONS ON A REAL ANALYTIC MANIFOLD Goulwen Fichou crossing singularities after a modification. We focus on the analytic equivalence of such functions with only normal crossing singularities. We prove that for such functions C right equivalence implies
Mechanics Systems on Para-Kaehlerian Manifolds of Constant J-Sectional Curvature
Mehmet Tekkoyun
2009-02-20T23:59:59.000Z
The goal of this paper is to present Euler-Lagrange and Hamiltonian equations on R2n which is a model of para-Kaehlerian manifolds of constant J-sectional curvature. In conclusion, some differential geometrical and physical results on the related mechanic systems have been given.
Carbon Nanotubes: Measuring Dispersion and Length
Fagan, Jeffrey A.; Bauer, Barry J.; Hobbie, Erik K.; Becker, Matthew L.; Hight-Walker, Angela; Simpson, Jeffrey R.; Chun, Jaehun; Obrzut, Jan; Bajpai, Vardhan; Phelan, Fred R.; Simien, Daneesh; Yeon Huh, Ji; Migler, Kalman B.
2011-03-01T23:59:59.000Z
Advanced technological uses of single-wall carbon nanotubes (SWCNTs) rely on the production of single length and chirality populations that are currently only available through liquid phase post processing. The foundation of all of these processing steps is the attainment of individualized nanotube dispersion in solution; an understanding of the collodial properties of the dispersed SWCNTs can then be used to designed appropriate conditions for separations. In many instances nanotube size, particularly length, is especially active in determining the achievable properties from a given population, and thus there is a critical need for measurement technologies for both length distribution and effective separation techniques. In this Progress Report, we document the current state of the art for measuring dispersion and length populations, including separations, and use examples to demonstrate the desirability of addressing these parameters.
Ceramics containing dispersants for improved fracture toughness
Nevitt, Michael V. (Wheaton, IL); Aldred, Anthony T. (Wheaton, IL); Chan, Sai-Kit (Darien, IL)
1987-01-01T23:59:59.000Z
The invention is a ceramic composition containing a new class of dispersant for hindering crack propagation by means of one or more energy-dissipative mechanisms. The composition is composed of a ceramic matrix with dispersed particles of a transformation-prone rare-earth niobate, tantalate or mixtures of these with each other and/or with a rare-earth vanadate. The dispersants, having a generic composition tRMO.sub.4, where R is a rare-earth element, B is Nb or Ta and O is oxygen, are mixed in powder form with a powder of the matrix ceramic and sintered to produce a ceramic form or body. The crack-hindering mechanisms operates to provide improved performance over a wide range of temperature and operating conditions.
Hamiltonian dynamics of breathers with third-order dispersion
Mookherjea, Shayan; Yariv, Amnon
2001-08-01T23:59:59.000Z
We present a nonperturbative analysis of certain dynamical aspects of breathers (dispersion-managed solitons) including the effects of third-order dispersion. The analysis highlights the similarities to and differences from the well-known analogous procedures for second-order dispersion. We discuss in detail the phase-space evolution of breathers in dispersion-managed systems in the presence of third-order dispersion. {copyright} 2001 Optical Society of America
SOLVENT DISPERSION AND FLOW METER CALCULATION RESULTS
Nash, C.; Fondeur, F.; Peters, T.
2013-06-21T23:59:59.000Z
Savannah River National Laboratory (SRNL) found that the dispersion numbers for the six combinations of CSSX:Next Generation Solvent (NGS) “blend” and pure NGS versus salt solution, caustic wash, and strip aqueous solutions are all good. The dispersion numbers are indications of processability with centrifugal contactors. A comparison of solvent physical and thermal properties shows that the Intek™ solvent flow meter in the plant has a reading biased high versus calibrated flow when NGS is used, versus the standard CSSX solvent. The flow meter, calibrated for CSSX solvent, is predicted to read 2.8 gpm of NGS in a case where the true flow of NGS is 2.16 gpm.
Method of dispersing particulate aerosol tracer
O'Holleran, Thomas P. (Belleville, MI)
1988-01-01T23:59:59.000Z
A particulate aerosol tracer which comprises a particulate carrier of sheet silicate composition having a particle size up to one micron, and a cationic dopant chemically absorbed in solid solution in the carrier. The carrier is preferably selected from the group consisting of natural mineral clays such as bentonite, and the dopant is selected from the group consisting of rare earth elements and transition elements. The tracers are dispersed by forming an aqueous salt solution with the dopant present as cations, dispersing the carriers in the solution, and then atomizing the solution under heat sufficient to superheat the solution droplets at a level sufficient to prevent reagglomeration of the carrier particles.
Reaction plane dispersion at intermediate energies
J. Lukasik; W. Trautmann
2006-03-29T23:59:59.000Z
A method to derive the corrections for the dispersion of the reaction plane at intermediate energies is proposed. The method is based on the correlated, non-isotropic Gaussian approximation. It allowed to construct the excitation function of genuine flow values for the Au+Au reactions at 40-150 MeV/nucleon measured with the INDRA detector at GSI.
Fall Rubber Colloquium CHARACTERIZATION OF DISPERSION
Paris-Sud XI, Université de
9th Fall Rubber Colloquium CHARACTERIZATION OF DISPERSION MECHANISMS OF AGGLOMERATED FILLERS (styrene-butadiene rubber). The objective was to determine the role of the intrinsic parameters Carbon black and silica are widely used as reinforcing fillers for rubber compounds in the tire industry
Extension of distributions, scalings and renormalization of QFT on Riemannian manifolds
Nguyen Viet Dang
2014-11-13T23:59:59.000Z
Let $M$ be a smooth manifold and $X\\subset M$ a closed subset of $M$. In this paper, we introduce a natural condition of \\emph{moderate growth} along $X$ for a distribution $t$ in $\\mathcal{D}^\\prime(M\\setminus X)$ and prove that this condition is equivalent to the existence of an extension of $t$ in $\\mathcal{D}^\\prime(M)$ generalizing some previous results of Meyer and Brunetti--Fredenhagen. When $X$ is a closed submanifold of $M$, we show that the concept of distributions with moderate growth coincides with weakly homogeneous distributions of Meyer. Then we renormalize products of distributions with functions tempered along $X$ and finally, using the whole analytical machinery developed, we give an existence proof of perturbative quantum field theories on Riemannian manifolds.
Victor Kalvin
2010-07-25T23:59:59.000Z
In this paper we continue our study of the Laplacian on manifolds with axial analytic asymptotically cylindrical ends initiated in~arXiv:1003.2538. By using the complex scaling method and the Phragm\\'{e}n-Lindel\\"{o}f principle we prove exponential decay of the eigenfunctions corresponding to the non-threshold eigenvalues of the Laplacian on functions. In the case of a manifold with (non-compact) boundary it is either the Dirichlet Laplacian or the Neumann Laplacian. We show that the rate of exponential decay of an eigenfunction is prescribed by the distance from the corresponding eigenvalue to the next threshold. Under our assumptions on the behaviour of the metric at infinity accumulation of isolated and embedded eigenvalues occur. The results on decay of eigenfunctions combined with the compactness argument due to Perry imply that the eigenvalues can accumulate only at thresholds and only from below. The eigenvalues are of finite multiplicity.
The Construction of Spinor Fields on Manifolds with Smooth Degenerate Metrics
J Schray; T Dray; C A Manogue; R W Tucker; C Wang
1996-05-17T23:59:59.000Z
We examine some of the subtleties inherent in formulating a theory of spinors on a manifold with a smooth degenerate metric. We concentrate on the case where the metric is singular on a hypersurface that partitions the manifold into Lorentzian and Euclidean domains. We introduce the notion of a complex spinor fibration to make precise the meaning of continuity of a spinor field and give an expression for the components of a local spinor connection that is valid in the absence of a frame of local orthonormal vectors. These considerations enable one to construct a Dirac equation for the discussion of the behavior of spinors in the vicinity of the metric degeneracy. We conclude that the theory contains more freedom than the spacetime Dirac theory and we discuss some of the implications of this for the continuity of conserved currents.
Quantization of a particle on a two-dimensional manifold of constant curvature
Bracken, Paul [Department of Mathematics, University of Texas, Edinburg, Texas 78540 (United States)
2014-10-15T23:59:59.000Z
The formulation of quantum mechanics on spaces of constant curvature is studied. It is shown how a transition from a classical system to the quantum case can be accomplished by the quantization of the Noether momenta. These can be determined by means of Lie differentiation of the metric which defines the manifold. For the metric examined here, it is found that the resulting Schrödinger equation is separable and the spectrum and eigenfunctions can be investigated in detail.
Energy identity of approximate biharmonic maps to Riemannian manifolds and its application
Wang, Changyou
2011-01-01T23:59:59.000Z
We consider in dimension four weakly convergent sequences of approximate biharmonic maps to a Riemannian manifold with bi-tension fields bounded in $L^p$ for $p>\\frac43$. We prove an energy identity that accounts for the loss of hessian energies by the sum of hessian energies over finitely many nontrivial biharmonic maps on $\\mathbb R^4$. As a corollary, we obtain an energy identity for the heat flow of biharmonic maps at time infinity.
Spinorial description of $\\mathrm{SU}(3)$- and $G_2$-manifolds
Ilka Agricola; Simon G. Chiossi; Thomas Friedrich; Jos Höll
2015-09-16T23:59:59.000Z
We present a uniform description of $\\mathrm{SU}(3)$-structures in dimension $6$ as well as $G_2$-structures in dimension $7$ in terms of a characterising spinor and the spinorial field equations it satisfies. We apply the results to hypersurface theory to obtain new embedding theorems, and give a general recipe for building conical manifolds. The approach also enables one to subsume all variations of the notion of a Killing spinor.
Perforation patterned electrical interconnects
Frey, Jonathan
2014-01-28T23:59:59.000Z
This disclosure describes systems and methods for increasing the usable surface area of electrical contacts within a device, such as a thin film solid state device, through the implementation of electrically conductive interconnects. Embodiments described herein include the use of a plurality of electrically conductive interconnects that penetrate through a top contact layer, through one or more multiple layers, and into a bottom contact layer. The plurality of conductive interconnects may form horizontal and vertical cross-sectional patterns. The use of lasers to form the plurality of electrically conductive interconnects from reflowed layer material further aids in the manufacturing process of a device.
Colloidal Manipulation of Nanostructures: Stable Dispersion and Self-assembly
Sun, Dazhi
2013-12-16T23:59:59.000Z
to disperse QDs and CNTs into polymeric matrices. Dispersion - property relationship in polymer nanocomposites has been systematically investigated with emphasis on optical properties for QDs and mechanical properties for CNTs....
On the reduction of oxygen from dispersed media
Roushdy, Omar H., 1977-
2007-01-01T23:59:59.000Z
The reduction of oxygen from an organic phase dispersed in a concentrated electrolyte is investigated. Dispersed organic phases are used to enhance oxygen transport in fermenters and artificial blood substitutes. This work ...
Update 4 to: A Dispersion Modeling Analysis of Downwash from...
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6 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant Modeling Baseload Units 3,4,5 Update 6 to: A Dispersion Modeling Analysis of Downwash from...
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5 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant: Modeling Cycling Units 1, 2 plus One Baseload Unit Update 5 to: A Dispersion Modeling...
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3 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant, Modeling Units 1 and 4 Together Update 3 to: A Dispersion Modeling Analysis of Downwash...
Broadband dispersion engineered microresonator on-a-chip
Yang, Ki Youl; Cole, Daniel C; Yi, Xu; Del'Haye, Pascal; Lee, Hansuek; Li, Jiang; Oh, Dong Yoon; Diddams, Scott A; Papp, Scott B; Vahala, Kerry J
2015-01-01T23:59:59.000Z
Control of dispersion in fibre optical waveguides is of critical importance to optical fibre communications systems and more recently for continuum generation from the ultraviolet to the mid-infrared. The wavelength at which the group velocity dispersion crosses zero can be set by varying fibre core diameter or index step. Moreover, sophisticated methods to manipulate higher-order dispersion so as shape and even flatten dispersion over wide bandwidths are possible using multi-cladding fibre. Here we introduce design and fabrication techniques that allow analogous dispersion control in chip-integrated optical microresonators, and thereby demonstrate higher-order, wide-bandwidth dispersion control over an octave of spectrum. Importantly, the fabrication method we employ for dispersion control simultaneously permits optical Q factors above 100 million, which is critical for efficient operation of nonlinear optical oscillators. Dispersion control in high Q systems has taken on greater importance in recent years w...
Dispersion modeling of ground-level area sources of particulate
Fritz, Bradley Keith
1998-01-01T23:59:59.000Z
The use of dispersion modeling by State Air Pollution hics. Regulatory Agencies (SAPRAS) is increasing. Dispersion modeling provides a quick and efficient means of determining the downwind impact of pollutant release from a source. The SAPRAS...
Geographic dispersion in teams : its history, experience, measurement, and change
O'Leary, Michael Boyer, 1969-
2002-01-01T23:59:59.000Z
This thesis begins with the simple argument that geographic dispersion has gone surprisingly unexamined despite its role as the domain-defining construct for geographically dispersed teams (a.k.a. "virtual teams"). The ...
Externally Dispersed Interferometry for Precision Radial Velocimetry
Erskine, D J; Muterspaugh, M W; Edelstein, J; Lloyd, J; Herter, T; Feuerstein, W M; Muirhead, P; Wishnow, E
2007-03-27T23:59:59.000Z
Externally Dispersed Interferometry (EDI) is the series combination of a fixed-delay field-widened Michelson interferometer with a dispersive spectrograph. This combination boosts the spectrograph performance for both Doppler velocimetry and high resolution spectroscopy. The interferometer creates a periodic spectral comb that multiplies against the input spectrum to create moire fringes, which are recorded in combination with the regular spectrum. The moire pattern shifts in phase in response to a Doppler shift. Moire patterns are broader than the underlying spectral features and more easily survive spectrograph blurring and common distortions. Thus, the EDI technique allows lower resolution spectrographs having relaxed optical tolerances (and therefore higher throughput) to return high precision velocity measurements, which otherwise would be imprecise for the spectrograph alone.
Some Thermodynamic Properties of Colloidal Dispersions
de Thier, Pierre
2013-01-01T23:59:59.000Z
In this paper, some results are derived to describe the out-of-equilibrium thermodynamics of colloidal suspensions. These results are obtained assuming that the properties of the colloids essentially come from their surfaces which are unusually high in comparison to their volume. The dispersion, in the form of a variable, is introduced in such a way as to embody the various changes which could affect those systems. Explicit relations are deduced for the free enthalpy of dispersion which describe two separated phenomena: the peptization/coalescence and the suspension of a colloidal phase. An alternative to the Gibbs' adsorption equation allows to explain how a surface relaxes thanks to adsorptions. Finally, a link between conformational entropy changes and surface entropy production is discussed with the idea to be applied to the well known protein folding problem.
Dispersion-free radial transmission lines
Caporaso, George J. (Livermore, CA); Nelson, Scott D. (Patterson, CA)
2011-04-12T23:59:59.000Z
A dispersion-free radial transmission line ("DFRTL") preferably for linear accelerators, having two plane conductors each with a central hole, and an electromagnetically permeable material ("EPM") between the two conductors and surrounding a channel connecting the two holes. At least one of the material parameters of relative magnetic permeability, relative dielectric permittivity, and axial width of the EPM is varied as a function of radius, so that the characteristic impedance of the DFRTL is held substantially constant, and pulse transmission therethrough is substantially dispersion-free. Preferably, the EPM is divided into concentric radial sections, with the varied material parameters held constant in each respective section but stepwise varied between sections as a step function of the radius. The radial widths of the concentric sections are selected so that pulse traversal time across each section is the same, and the varied material parameters of the concentric sections are selected to minimize traversal error.
Plasmon dispersion in strongly correlated superlattices
Lu, D. [Department for Intensive Instruction, Nanjing University, Nanjing 210093, People`s Republic of (China)] [Department for Intensive Instruction, Nanjing University, Nanjing 210093, People`s Republic of (China); Golden, K.I. [Department of Mathematics and Statistics, University of Vermont, Burlington, Vermont 05405 (United States)] [Department of Mathematics and Statistics, University of Vermont, Burlington, Vermont 05405 (United States); Kalman, G. [Department of Physics, Boston College, Chestnut Hill, Massachusetts 02167 (United States)] [Department of Physics, Boston College, Chestnut Hill, Massachusetts 02167 (United States); Wyns, P. [Hewlett-Packard Colorado Integrated Circuits Division, M.S. 64, 3404 East Harmony Road, Fort Collins, Colorado 80525 (United States)] [Hewlett-Packard Colorado Integrated Circuits Division, M.S. 64, 3404 East Harmony Road, Fort Collins, Colorado 80525 (United States); Miao, L. [Department of Computer Science and Electrical Engineering, University of Vermont, Burlington, Vermont 05405 (United States)] [Department of Computer Science and Electrical Engineering, University of Vermont, Burlington, Vermont 05405 (United States); Shi, X. [Department of Physics, Nanjing University, Nanjing 210008, People`s Republic of (China)] [Department of Physics, Nanjing University, Nanjing 210008, People`s Republic of (China)
1996-10-01T23:59:59.000Z
The dielectric response function of a strongly correlated superlattice is calculated in the quasilocalized charge (QLC) approximation. The resulting QLC static local-field correction, which contains both intralayer and interlayer pair-correlational effects, is identical to the correlational part of the third-frequency-moment sum-rule coefficient. This approximation treats the interlayer and intralayer couplings on an equal footing. The resulting dispersion relation is first analyzed to determine the effect of intralayer coupling on the out-of-phase acoustic-mode dispersion; in this approximation the interlayer coupling is suppressed and the mutual interaction of the layers is taken into account only through the average random-phase approximation (RPA) field. In the resulting mode dispersion, the onset of a finite-{ital k} ({ital k} being the in-plane wave number) reentrant low-frequency excitation developing (with decreasing {ital d}/{ital a}) into a dynamical instability is indicated ({ital a} being the in-plane Wigner-Seitz radius and {ital d} the distance between adjacent lattice planes). This dynamical instability parallels a static structural instability reported earlier both for a bilayer electron system and a superlattice and presumably indicates a structural change in the electron liquid. If one takes account of interlayer correlations beyond the RPA, the acoustic excitation spectrum is dramatically modified by the appearance of an energy gap which also has a stabilizing effect on the instability. We extend a previous energy gap study at {ital k}=0 [G. Kalman, Y. Ren, and K. I. Golden, Phys Rev. B {bold 50}, 2031 (1994)] to a calculation of the dispersion of the gapped acoustic excitation spectrum in the long-wavelength domain. {copyright} {ital 1996 The American Physical Society.}
Composite materials with improved phyllosilicate dispersion
Chaiko, David J.
2004-09-14T23:59:59.000Z
The present invention provides phyllosilicates edge modified with anionic surfactants, composite materials made from the edge modified phyllosilicates, and methods for making the same. In various embodiments the phyllosilicates are also surface-modified with hydrophilic lipophilic balance (HLB) modifying agents, polymeric hydrotropes, and antioxidants. The invention also provides blends of edge modified phyllosilicates and semicrystalline waxes. The composite materials are made by dispersing the edge modified phyllosilicates with polymers, particularly polyolefins and elastomers.
Applicability of a fog-dispersal system
Fourroux, Melvin Ross
1973-01-01T23:59:59.000Z
operations. zv A comprehensive review and evaluation of both past and present systems of warm fog dispersal indicates that the most reliable system available is a ground-based thermal system. The surface winds observed during periods of fog suggest... drawing of an underground blower unit 88 27. layout of the Vandenberg AFB test area. . . . . . 28. Flow diagram of the Vandenberg AFB heating system. 94 29. NcChord AFB runway complex and instrumentation. . 102 30. Terrain profile from the decision...
Determination of Longitudinal Dispersion Coefficient and Net
Ho, David
with a Large-Scale, High Resolution SF6 Tracer Release Experiment D A V I D T . H O , * , P E T E R S C H L O into rivers. In the following, we report results from a large-scale SF6 tracer release experiment conducted in the tidal Hudson River to examine longitudinal dispersion and net advection. SF6 was injected
Urban dispersion : challenges for fast response modeling
Brown, M. J. (Michael J.)
2004-01-01T23:59:59.000Z
There is renewed interest in urban dispersion modeling due to the need for tools that can be used for responding to, planning for, and assessing the consequences of an airborne release of toxic materials. Although not an everyday phenomenon, releases of hazardous gases and aerosols have occurred in populated urban environments and are potentially threatening to human life. These releases may stem from on-site accidents as in the case of industrial chemical releases, may result during transport of hazardous chemicals as in tanker truck or railroad spills, or may be premeditated as in a chemical, biological, or radiological (CBR) agent terrorist attack. Transport and dispersion in urban environments is extremely complicated. Buildings alter the flow fields and deflect the wind, causing updrafts and downdrafts, channeling between buildings, areas of calm winds adjacent to strong winds, and horizontally and vertically rotating-eddies between buildings, at street corners, and other places within the urban canopy (see review by Hosker, 1984). Trees, moving vehicles, and exhaust vents among other things further complicate matters. The distance over which chemical, biological, or radiological releases can be harmful varies from tens of meters to many kilometers depending on the amount released, the toxicity of the agent, and the atmospheric conditions. As we will show later, accounting for the impacts of buildings on the transport and dispersion is crucial in estimating the travel direction, the areal extent, and the toxicity levels of the contaminant plume, and ultimately for calculating exposures to the population.
Dispersants Forum: Gulf of Mexico Oil Spill & Ecosystem Science
New Hampshire, University of
Dispersants Forum: Gulf of Mexico Oil Spill & Ecosystem Science Conference What have we & Restoration, Gulf of Mexico Disaster Response Center 2.3. Characterizing Dispersant and Dispersed Oil Effects The content for this workshop was developed in cooperation with the Gulf of Mexico Research Initiative (Go
A Smooth Interface Method for Simulating Liquid Crystal Colloid Dispersions
A Smooth Interface Method for Simulating Liquid Crystal Colloid Dispersions Ryoichi Yamamoto is presented for mesoscopic simulations of particle dispersions in liquid crystal solvents. It allows efficient mediated by the solvents. Demonstrations have been performed for the aggregation of colloid dispersions
Tropical cyclone energy dispersion under vertical shears Xuyang Ge,1
Li, Tim
Tropical cyclone energy dispersion under vertical shears Xuyang Ge,1 Tim Li,1,2 and Xiaqiong Zhou1] Tropical cyclone Rossby wave energy dispersion under easterly and westerly vertical shears is investigated, and X. Zhou (2007), Tropical cyclone energy dispersion under vertical shears, Geophys. Res. Lett., 34, L
Kelley; Dana A. (New Milford, CT), Farooque; Mohammad (Danbury, CT), Davis; Keith (Southbury, CT)
2007-10-02T23:59:59.000Z
A fuel cell system with improved electrical isolation having a fuel cell stack with a positive potential end and a negative potential, a manifold for use in coupling gases to and from a face of the fuel cell stack, an electrical isolating assembly for electrically isolating the manifold from the stack, and a unit for adjusting an electrical potential of the manifold such as to impede the flow of electrolyte from the stack across the isolating assembly.
Tin, Marie-Lyne Appoline
1992-01-01T23:59:59.000Z
fulfiffment of the requirements for tht (Iecffce ol' ~IASTErt OF SCIf X& l. : Decenit&er 1999 ttla jor Sul~ ject: 1;jr i trical I;ngineerin~ DISCRETE TIME ROBUST CONTROL SYSTEMS UNDER STRUCTURFD PERTURBATIONS: STABILITY MANIFOLDS AND EXTREMAL PROPERTIES... A Thesis by MARIE-LYNE APPOLINE TIN Approved as to style and content by: S. P. Bhattacharyya (Chair of Committee) A. Datta. ('t'lend&er) L Howz (Member) . Parlos lr1eniher) A. Patton (Head of Department) December I'19'2 ABSTRACT...
Eigenvalues of Killing Tensors and Separable Webs on Riemannian and Pseudo-Riemannian Manifolds
Claudia Chanu; Giovanni Rastelli
2007-02-12T23:59:59.000Z
Given a $n$-dimensional Riemannian manifold of arbitrary signature, we illustrate an algebraic method for constructing the coordinate webs separating the geodesic Hamilton-Jacobi equation by means of the eigenvalues of $m \\leq n$ Killing two-tensors. Moreover, from the analysis of the eigenvalues, information about the possible symmetries of the web foliations arises. Three cases are examined: the orthogonal separation, the general separation, including non-orthogonal and isotropic coordinates, and the conformal separation, where Killing tensors are replaced by conformal Killing tensors. The method is illustrated by several examples and an application to the L-systems is provided.
Mariz, T.; Menezes, R.; Nascimento, J.R.S.; Ribeiro, R.F. [Departamento de Fisica, Universidade Federal da Paraiba, 58051-970 Joao Pessoa, Paraiba (Brazil); Wotzasek, C. [Instituto de Fisica, Universidade Federal do Rio de Janeiro, 21945 Rio de Janeiro (Brazil)
2004-10-15T23:59:59.000Z
We study issues of duality and dual equivalence in noncommutative manifolds. In particular, the question of dual equivalence for the actions of the noncommutative extensions of the self-dual model in 3D space-time and the Maxwell-Chern-Simons model is investigated. We show that former model is not dual equivalent to the noncommutative extension of the Maxwell-Chern-Simons model, as widely believed, but a deformed version of it that is disclosed here. Our results are not restricted to any finite order in the Seiberg-Witten expansion involving the noncommutative parameter {theta}.
SO(10) Grand Unification in M theory on a G2 manifold
Acharya, Bobby S; Romao, Miguel Crispim; King, Stephen F; Pongkitivanichkul, Chakrit
2015-01-01T23:59:59.000Z
We consider Grand Unified Theories based on $SO(10)$ which originate from string/$M$ theory on $G_2$ manifolds or Calabi-Yau spaces with discrete symmetries. In this framework we are naturally led to a novel solution of the doublet-triplet splitting problem previously considered by Dvali which involves an extra vector-like Standard Model family and light, but weakly coupled colour triplets. These additional states are predicted to be accessible at the LHC and also induce R-parity violation. Gauge coupling unification occurs with a larger GUT coupling.
SO(10) Grand Unification in M theory on a G2 manifold
Bobby S. Acharya; Krzysztof Bozek; Miguel Crispim Romao; Stephen F. King; Chakrit Pongkitivanichkul
2015-02-05T23:59:59.000Z
We consider Grand Unified Theories based on $SO(10)$ which originate from string/$M$ theory on $G_2$ manifolds or Calabi-Yau spaces with discrete symmetries. In this framework we are naturally led to a novel solution of the doublet-triplet splitting problem previously considered by Dvali which involves an extra vector-like Standard Model family and light, but weakly coupled colour triplets. These additional states are predicted to be accessible at the LHC and also induce R-parity violation. Gauge coupling unification occurs with a larger GUT coupling.
Dispersed Project Wind Farm | Open Energy Information
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousPlasmaP a g eWorksVillagesource History(Redirected from DavisDeveloperEnergyDirect-CurrentDispersed Project
Economics of selected WECS dispersed applications
Krawiec, S.
1980-02-01T23:59:59.000Z
An economic analysis for distributed Wind Energy Conversion Systems (WECS) was conducted for the Department of Energy (DOE) as part of the Solar Commercial Readiness Assessment task at the Solar Energy Research Institute (SERI). The major objective of the study is to analyze: the cost of electricity generated by selected wind energy systems in residential and agricultural applications; the breakeven cost of wind systems able to compete economically with conventional power sources in dispersed applications; and the impact of major economic factors on the cost performance index.
Falicoff, Waqidi; Chaves, Julio C.; Minano, Juan Carlos; Benitez, Pablo; Dross, Oliver; Parkyn, Jr., William A.
2010-02-23T23:59:59.000Z
Optical systems are described that have at least one source of a beam of blue light with divergence under 15.degree.. A phosphor emits yellow light when excited by the blue light. A collimator is disposed with the phosphor and forms a yellow beam with divergence under 15.degree.. A dichroic filter is positioned to transmit the beam of blue light to the phosphor and to reflect the beam of yellow light to an exit aperture. In different embodiments, the beams of blue and yellow light are incident upon said filter with central angles of 15.degree., 22.degree., and 45.degree.. The filter may reflect all of one polarization and part of the other polarization, and a polarization rotating retroreflector may then be provided to return the unreflected light to the filter.
Pauwels, M.A.; Wright, D.O.
1986-07-15T23:59:59.000Z
A microprocessor based electronic engine control system is described for an internal combustion engine, a method for updating the stored ambient pressure signal by measuring the ambient barometric pressure during engine operation using a manifold pressure sensor. The method consists of: generating timing signals indicating the rotational position of an engine member and including a signal indicating a predetermined rotational position in the rotation of the engine member; generating a pressure signal from the manifold pressure sensor representing the pressure surrounding the sensor in response to the predetermined rotational position; reading the value of ambient barometric pressure stored in the memory of the microprocessor; comparing the value of the barometric pressure stored in the memory of the microprocessor and the value of the pressure signal; increasing the value of the barometric pressure by one unit to generate a new barometric pressure value when the value of the pressure signal is greater than the value of the barometric pressure; comparing the new barometric pressure value with a predetermined fixed constant representing the maximum barometric pressure; and storing in the memory of the microprocessor either the new barometric pressure value if equal to or less than the fixed constant or the value of the maximum barometric pressure if the new barometric pressure value is greater than the fixed constant.
Carmeline J. Dsilva; Ronen Talmon; Ronald R. Coifman; Ioannis G. Kevrekidis
2015-05-22T23:59:59.000Z
Nonlinear manifold learning algorithms, such as diffusion maps, have been fruitfully applied in recent years to the analysis of large and complex data sets. However, such algorithms still encounter challenges when faced with real data. One such challenge is the existence of "repeated eigendirections," which obscures the detection of the true dimensionality of the underlying manifold and arises when several embedding coordinates parametrize the same direction in the intrinsic geometry of the data set. We propose an algorithm, based on local linear regression, to automatically detect coordinates corresponding to repeated eigendirections. We construct a more parsimonious embedding using only the eigenvectors corresponding to unique eigendirections, and we show that this reduced diffusion maps embedding induces a metric which is equivalent to the standard diffusion distance. We first demonstrate the utility and flexibility of our approach on synthetic data sets. We then apply our algorithm to data collected from a stochastic model of cellular chemotaxis, where our approach for factoring out repeated eigendirections allows us to detect changes in dynamical behavior and the underlying intrinsic system dimensionality directly from data.
Global dynamics and inflationary center manifold and slow-roll approximants
Artur Alho; Claes Uggla
2015-01-15T23:59:59.000Z
We consider the familiar problem of a minimally coupled scalar field with quadratic potential in flat Friedmann-Lema\\^itre-Robertson-Walker cosmology to illustrate a number of techniques and tools, which can be applied to a wide range of scalar field potentials and problems in e.g. modified gravity. We present a global and regular dynamical systems description that yields a global understanding of the solution space, including asymptotic features. We introduce dynamical systems techniques such as center manifold expansions and use Pad\\'e approximants to obtain improved approximations for the `attractor solution' at early times. We also show that future asymptotic behavior is associated with a limit cycle, which shows that manifest self-similarity is asymptotically broken toward the future, and give approximate expressions for this behavior. We then combine these results to obtain global approximations for the attractor solution, which, e.g., might be used in the context of global measures. In addition we elucidate the connection between slow-roll based approximations and the attractor solution, and compare these approximations with the center manifold based approximants.
Hyper dispersion pulse compressor for chirped pulse amplification systems
Barty, Christopher P. J. (Hayward, CA)
2011-11-29T23:59:59.000Z
A grating pulse compressor configuration is introduced for increasing the optical dispersion for a given footprint and to make practical the application for chirped pulse amplification (CPA) to quasi-narrow bandwidth materials, such as Nd:YAG. The grating configurations often use cascaded pairs of gratings to increase angular dispersion an order of magnitude or more. Increased angular dispersion allows for decreased grating separation and a smaller compressor footprint.
A Smooth Interface Method for Simulating Liquid Crystal Colloid Dispersions
Ryoichi Yamamoto; Yasuya Nakayama; Kang Kim
2003-10-30T23:59:59.000Z
A new method is presented for mesoscopic simulations of particle dispersions in liquid crystal solvents. It allows efficient first-principle simulations of the dispersions involving many particles with many-body interactions mediated by the solvents. Demonstrations have been performed for the aggregation of colloid dispersions in two-dimensional nematic and smectic-C* solvents neglecting hydrodynamic effects, which will be taken into account in the near future.
Process for producing dispersed particulate composite materials
Henager, Jr., Charles H. (Richland, WA); Hirth, John P. (Viola, ID)
1995-01-01T23:59:59.000Z
This invention is directed to a process for forming noninterwoven dispersed particulate composite products. In one case a composite multi-layer film product comprises a substantially noninterwoven multi-layer film having a plurality of discrete layers. This noninterwoven film comprises at least one discrete layer of a first material and at least one discrete layer of a second material. In another case the first and second materials are blended together with each other. In either case, the first material comprises a metalloid and the second material a metal compound. At least one component of a first material in one discrete layer undergoes a solid state displacement reaction with at least one component of a second material thereby producing the requisite noninterwoven composite film product. Preferably, the first material comprises silicon, the second material comprises Mo.sub.2 C, the third material comprises SiC and the fourth material comprises MoSi.sub.2.
Dispersion compensation in chirped pulse amplification systems
Bayramian, Andrew James; Molander, William A.
2014-07-15T23:59:59.000Z
A chirped pulse amplification system includes a laser source providing an input laser pulse along an optical path. The input laser pulse is characterized by a first temporal duration. The system also includes a multi-pass pulse stretcher disposed along the optical path. The multi-pass pulse stretcher includes a first set of mirrors operable to receive input light in a first plane and output light in a second plane parallel to the first plane and a first diffraction grating. The pulse stretcher also includes a second set of mirrors operable to receive light diffracted from the first diffraction grating and a second diffraction grating. The pulse stretcher further includes a reflective element operable to reflect light diffracted from the second diffraction grating. The system further includes an amplifier, a pulse compressor, and a passive dispersion compensator disposed along the optical path.
Method for dispersing catalyst onto particulate material
Utz, Bruce R. (Pittsburgh, PA); Cugini, Anthony V. (Pittsburgh, PA)
1992-01-01T23:59:59.000Z
A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal.
Effect of the Ligand Shell Composition on the Dispersibility...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Dispersibility-vs-density plots are obtained by following the variation in the Surface Plasmon Resonance (SPR) absorption spectra of the nanoparticles. To better understand the...
Electronic dispersion in two overlapping graphene sheets: Impacts...
Office of Scientific and Technical Information (OSTI)
Conference: Electronic dispersion in two overlapping graphene sheets: Impacts of long-range atomic ordering and periodic potentials. Citation Details In-Document Search Title:...
Update 1 to: A Dispersion Modeling Analysis of Downwash from...
Broader source: Energy.gov (indexed) [DOE]
Update 1 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant, Modeling Unit 1 Emissions in a Cycling Mode More Documents & Publications Update 3...
Dispersivity estimates from a tracer experiment in a sandy aquifer
Mallants, D.; Espino, A.; Van Hoorick, M.; Feyen, J.; Vandenberghe, N.; Loy, W.
2000-04-01T23:59:59.000Z
The success or failure of transport models in predicting the migration of a contaminant plume is ground water depends to a large extent on the quality of flow and transport parameters used. In this study, the authors investigate the spatial variability in the tracer velocity and dispersivity in a shallow sandy aquifer in northern Belgium. Based on hydraulic conductivity measurements on cores sampled along a vertical profile, the aquifer was found to be mildly heterogeneous, i.e., with the variance of the log-transformed conductivity K, {sigma}{sup 2}{sub lnK}, equal to 0.22. By means of a natural gradient tracer experiment, transport of a chloride tracer was investigated in a three-dimensional network of multilevel point samplers (MLS). Least squares fitting of a two-dimensional transport model to the individual breakthrough curves resulted in an average longitudinal dispersivity that was 10 times larger than the transverse dispersivity. The results further showed the existence of a dispersion-scale effect whereby the depth-averaged longitudinal dispersivity increases with increasing travel distance. The average longitudinal dispersivity corresponding to a travel distance of 10 m was equal to 0.2 m. The authors finally show that theoretical expressions for the macroscopic dispersivity tensor, which require input on hydraulic conductivity heterogeneity, could be used here to approximate the observed dispersive behavior. These conceptually simple models are useful to estimate macroscopic dispersivities when no tracer data are available.
On a hierarchy of nonlinearly dispersive generalized Korteweg...
Office of Scientific and Technical Information (OSTI)
On a hierarchy of nonlinearly dispersive generalized Korteweg - de Vries evolution equations Citation Details In-Document Search This content will become publicly available on...
Three Dimensioanl Free Electron Laser Dispersion Relation Including Betatron Oscillations
Chin, Y.H.
2011-01-01T23:59:59.000Z
Three-Dimensional Free Electron Laser Dispersion RelationInternational Free Electron Laser Conference, Santa Fe, NM,International Free Electron Laser Conference, held in Santa
Powder diffraction studies using anomalous dispersion
Cox, D.E. [Brookhaven National Lab., Upton, NY (United States); Wilkinson, A.P. [California Univ., Santa Barbara, CA (United States). Dept. of Materials
1993-05-01T23:59:59.000Z
With the increasing availability and accessibility of high resolution powder diffractometers at many synchrotron radiation sources throughout the world, there is rapidly-growing interest in the exploitation of anomalous dispersion techniques for structural studies of polycrystalline materials. In conjunction with the Rietveld profile method for structure refinement, such studies are especially useful for the determination of the site distributions of two or more atoms which are near neighbors in the periodic table, or atoms which are distributed among partially occupied sites. Additionally, it is possible to (1) determine the mean-square displacements associated with different kinds of atoms distributed over a single set of sites, (2) distinguish between different oxidation states and coordination geometries of a particular atom in a compound and (3) to determine f` for a wide range of atomic species as a function of energy in the vicinity of an absorption edge. Experimental methods for making anomalous dispersion measurements are described in some detail, including data collection strategies, data analysis and correlation problems, possible systematic errors, and the accuracy of the results. Recent work in the field is reviewed, including cation site-distribution studies (e.g. doped high {Tc} superconductors, ternary alloys, FeCo{sub 2}(PO{sub 4}){sub 3}, FeNi{sub 2}BO{sub 5}), oxidation-state contrast (e.g. YBa{sub 2}Cu{sub 3}O{sub 6+x}, Eu{sub 3}O{sub 4}, GaCl{sub 2}, Fe{sub 2}PO{sub 5}), and the effect of coordination geometry (e.g. Y{sub 3}Ga{sub 5}O{sub l2}).
Powder diffraction studies using anomalous dispersion
Cox, D.E. (Brookhaven National Lab., Upton, NY (United States)); Wilkinson, A.P. (California Univ., Santa Barbara, CA (United States). Dept. of Materials)
1993-01-01T23:59:59.000Z
With the increasing availability and accessibility of high resolution powder diffractometers at many synchrotron radiation sources throughout the world, there is rapidly-growing interest in the exploitation of anomalous dispersion techniques for structural studies of polycrystalline materials. In conjunction with the Rietveld profile method for structure refinement, such studies are especially useful for the determination of the site distributions of two or more atoms which are near neighbors in the periodic table, or atoms which are distributed among partially occupied sites. Additionally, it is possible to (1) determine the mean-square displacements associated with different kinds of atoms distributed over a single set of sites, (2) distinguish between different oxidation states and coordination geometries of a particular atom in a compound and (3) to determine f' for a wide range of atomic species as a function of energy in the vicinity of an absorption edge. Experimental methods for making anomalous dispersion measurements are described in some detail, including data collection strategies, data analysis and correlation problems, possible systematic errors, and the accuracy of the results. Recent work in the field is reviewed, including cation site-distribution studies (e.g. doped high [Tc] superconductors, ternary alloys, FeCo[sub 2](PO[sub 4])[sub 3], FeNi[sub 2]BO[sub 5]), oxidation-state contrast (e.g. YBa[sub 2]Cu[sub 3]O[sub 6+x], Eu[sub 3]O[sub 4], GaCl[sub 2], Fe[sub 2]PO[sub 5]), and the effect of coordination geometry (e.g. Y[sub 3]Ga[sub 5]O[sub l2]).
Daraio, Chiara
Keywords: Microchannel heat sink Electronics cooling Energy Exergy Efficiency Turbulent flow a b s t r a c t A detailed thermo-hydrodynamic analysis of a hot water cooled manifold microchannel heat sink for electronic. The energetic performance of the heat sink is analyzed in terms of 2nd law efficiency and sources of exergy
Fern, Xiaoli Zhang
of organization. Audio classification systems typically begin by extract- ing acoustic features from audio signalsAudio Classification of Bird Species: a Statistical Manifold Approach Forrest Briggs, Raviv Raich}@eecs.oregonstate.edu Abstract Our goal is to automatically identify which species of bird is present in an audio recording using
Pless, Robert
Manifold Learning for 4D CT Reconstruction of the Lung Manfred Georg*, Richard Souvenir, Andrew, Canada Andrew.Hope@rmp.uhn.on.ca Abstract Computed Tomography is used to create models of lung dynamics because it provides high contrast images of lung tissue. Creating 4D CT models which capture dynamics
Pope, Christopher
Geometry and Group Theory ABSTRACT In this course, we develop the basic notions of Manifolds and Geometry, with applications in physics, and also we develop the basic notions of the theory of Lie Groups . . . . . . . . . . . . . . . . . . . . . 66 2 General Relativity; Einstein's Theory of Gravitation 73 2.1 The Equivalence Principle
Numerical Computation of the Stable and Unstable Manifolds of Invariant Tori
Derin B. Wysham; James D. Meiss
2005-04-26T23:59:59.000Z
We develop an iterative technique for computing the unstable and stable eigenfunctions of the invariant tori of diffeomorphisms. Using the approach of Jorba, the linearized equations are rewritten as a generalized eigenvalue problem. Casting the system in this light allows us to take advantage of the speed of eigenvalue solvers and create an efficient method for finding the first order approximations to the invariant manifolds of the torus. We present a numerical scheme based on the power method that can be used to determine the behavior normal to such tori, and give some examples of the application of the method. We confirm the qualitative conclusions of the Melnikov calculations of Lomel\\'i and Meiss (2003) for a volume-preserving mapping.
Solid oxide fuel cell having monolithic cross flow core and manifolding
Poeppel, R.B.; Dusek, J.T.
1983-10-12T23:59:59.000Z
This invention discloses a monolithic core construction having the flow passageways for the fuel and for the oxidant gases extended transverse to one another, whereby full face core manifolding can be achieved for these gases and their reaction products. The core construction provides that only anode material surround each fuel passageway and only cathode material surround each oxidant passageway, each anode and each cathode further sandwiching at spaced opposing sides electrolyte and interconnect materials to define electrolyte and interconnect walls. Webs of the cathode and anode material hold the electrolyte and interconnect walls spaced apart to define the flow passages. The composite anode and cathode wall structures are further alternately stacked on one another (with the separating electrolyte or interconnect material typically being a single common layer) whereby the fuel passageways and the oxidant passageways are disposed transverse to one another.
Solid oxide fuel cell having monolithic cross flow core and manifolding
Poeppel, Roger B. (Glen Ellyn, IL); Dusek, Joseph T. (Downers Grove, IL)
1984-01-01T23:59:59.000Z
This invention discloses a monolithic core construction having the flow passageways for the fuel and for the oxidant gases extended transverse to one another, whereby full face core manifolding can be achieved for these gases and their reaction products. The core construction provides that only anode material surround each fuel passageway and only cathode material surround each oxidant passageway, each anode and each cathode further sandwiching at spaced opposing sides electrolyte and interconnect materials to define electrolyte and interconnect walls. Webs of the cathode and anode material hold the electrolyte and interconnect walls spaced apart to define the flow passages. The composite anode and cathode wall structures are further alternately stacked on one another (with the separating electrolyte or interconnect material typically being a single common layer) whereby the fuel passageway and the oxidant passageways are disposed transverse to one another.
Manifold, bus support and coupling arrangement for solid oxide fuel cells
Parry, G.W.
1988-04-21T23:59:59.000Z
Individual, tubular solid oxide fuel cells (SOFCs) are assembled into bundles called a module within a housing, with a plurality of modules arranged end-to-end in a linear, stacked configuration called a string. A common set of piping comprised of a suitable high temperature resistant material (1) provides fuel and air to each module housing, (2) serves as electrically conducting buses, and (3) provides structural support for a string of SOFC modules. Ceramic collars are used to connect fuel and air inlet piping to each of the electrodes in an SOFC module and provide (1) electrical insulation for the current carrying bus bars and gas manifolds, (2) damping for the fuel and air inlet piping, and (3) proper spacing between the fuel and air inlet piping to prevent contact between these tubes and possible damage to the SOFC. 11 figs.
$SO(10)$ Grand Unification from $M$ theory on a $G_2$ manifold
Miguel Crispim Romão
2015-02-20T23:59:59.000Z
We consider Grand Unified Theories based on $SO(10)$ which originate from $M$ theory on $G_2$ manifolds. In this framework we are naturally led to a novel solution of the doublet-triplet splitting problem involving an extra $\\overline{{\\bf 16}}_X+{\\bf 16}_X$ vector-like pair by considering discrete symmetries of the extra dimensions and preserving unification. Since Wilson line breaking preserves the rank of the gauge group, the necessary $U(1)$ gauge breaking is generated from extra multiplets. The main prediction of the approach is the existence of light states with the quantum numbers of a $\\overline{{\\bf 16}}_X+{\\bf 16}_X$ vector-like pair which could show up in future LHC searches.
$SO(10)$ Grand Unification from $M$ theory on a $G_2$ manifold
Romão, Miguel Crispim
2015-01-01T23:59:59.000Z
We consider Grand Unified Theories based on $SO(10)$ which originate from $M$ theory on $G_2$ manifolds. In this framework we are naturally led to a novel solution of the doublet-triplet splitting problem involving an extra $\\overline{{\\bf 16}}_X+{\\bf 16}_X$ vector-like pair by considering discrete symmetries of the extra dimensions and preserving unification. Since Wilson line breaking preserves the rank of the gauge group, the necessary $U(1)$ gauge breaking is generated from extra multiplets. The main prediction of the approach is the existence of light states with the quantum numbers of a $\\overline{{\\bf 16}}_X+{\\bf 16}_X$ vector-like pair which could show up in future LHC searches.
The quintic nonlinear Schr\\"odinger equation on three-dimensional Zoll manifolds
Herr, Sebastian
2011-01-01T23:59:59.000Z
Let (M,g) be a three-dimensional smooth compact Riemannian manifold such that all geodesics are simple and closed with a common minimal period, such as the 3-sphere S^3 with canonical metric. In this work the global well-posedness problem for the quintic nonlinear Schr\\"odinger equation i\\partial_t u+\\Delta u=\\pm|u|^4u, u|_{t=0}=u_0 is solved for small initial data u_0 in the energy space H^1(M), which is the scaling-critical space. Moreover, local well-posedness is shown for large data, as well as persistence of higher initial Sobolev regularity. This extends previous results of Burq-G\\'erard-Tzvetkov to the endpoint case.
P. M. Sutter; Tsunefumi Tanaka
2006-10-11T23:59:59.000Z
Although the observed universe appears to be geometrically flat, it could have one of 18 global topologies. A constant-time slice of the spacetime manifold could be a torus, Mobius strip, Klein bottle, or others. This global topology of the universe imposes boundary conditions on quantum fields and affects the vacuum energy density via Casimir effect. In a spacetime with such a nontrivial topology, the vacuum energy density is shifted from its value in a simply-connected spacetime. In this paper, the vacuum expectation value of the stress-energy tensor for a massless scalar field is calculated in all 17 multiply-connected, flat and homogeneous spacetimes with different global topologies. It is found that the vacuum energy density is lowered relative to the Minkowski vacuum level in all spacetimes and that the stress-energy tensor becomes position-dependent in spacetimes that involve reflections and rotations.
On a nonlocal dispersive equation modeling particle suspensions
Zumbrun, Kevin
On a nonlocal dispersive equation modeling particle suspensions Kevin Zumbrun July, 1996 Abstract: We study a nonlocal, scalar conservation law, u t + ((K a \\Lambda u)u) x = 0, modeling sedimentation, and \\Lambda represents convolution. We show this to be a dispersive regularization of the Hopf equation, u
Series evaluation of Tweedie exponential dispersion model densities
Smyth, Gordon K.
of Mathematics and Computing University of Southern Queensland Toowoomba, Qld 4350, Australia Gordon K. Smyth 3052, Australia smyth@wehi.edu.au 23 February 2005 Abstract Exponential dispersion models, which for generalized linear models. The Tweedie families are those exponential dispersion models with power mean
Short communication Study of pollution dispersion in urban areas using
Yu, Peter K.N.
Short communication Study of pollution dispersion in urban areas using Computational Fluid Dynamics of emissions from vehicles traversing the streets. Information on the layouts and heights of buildings.5 to construct the geometry for simulations. The dispersion characteristics, such as the spread of the pollution
A study of micro fiber dispersion using digital image analysis
Hendrarsakti, Jooned
2004-11-15T23:59:59.000Z
of this dissertation is to investigate the use of texture analysis as a tool to micro fiber dispersion measurement. Micro fiber dispersion can be found in many applications such as in paper and industry powder engineering. Three cases related to micro fiber...
Antagonistic effects of seed dispersal and herbivory on plant migration
Vellend, Mark
LETTER Antagonistic effects of seed dispersal and herbivory on plant migration Mark Vellend,1@interchange.ubc.ca Abstract The two factors that determine plant migration rates seed dispersal and population growth are generally treated independently, despite the fact that many animals simultaneously enhance plant migration
Atmospheric dispersion index for prescribed burning. Forest Service research paper
Lavdas, L.G.
1986-10-01T23:59:59.000Z
A numerical index that estimates the atmosphere's capacity to disperse smoke from prescribed burning is described. The physical assumptions and mathematical development of the index are given in detail. A preliminary interpretation of dispersion index values is offered. A FORTRAN subroutine package for computing the index is included.
Leonid Lantsman
2010-08-17T23:59:59.000Z
We intend to show that the vacuum manifold inherent in the Minkowskian non-Abelian model involving Higgs and Yang-Mills BPS vacuum modes and herewith quantized by Dirac can be described with the help of the superselection rules if and only if the "discrete" geometry for this vacuum manifold is assumed (it is just a necessary thing in order justify the Dirac fundamental quantization scheme applied to the mentioned model) and only in the infinitely narrow spatial region of the cylindrical shape where topologically nontrivial vortices are located inside this discrete vacuum manifold.
Modelling long-distance seed dispersal in heterogeneous landscapes.
Levey, Douglas, J.; Tewlsbury, Joshua, J.; Bolker, Benjamin, M.
2008-01-01T23:59:59.000Z
1. Long-distance seed dispersal is difficult to measure, yet key to understanding plant population dynamics and community composition. 2. We used a spatially explicit model to predict the distribution of seeds dispersed long distances by birds into habitat patches of different shapes. All patches were the same type of habitat and size, but varied in shape. They occurred in eight experimental landscapes, each with five patches of four different shapes, 150 m apart in a matrix of mature forest. The model was parameterized with smallscale movement data collected from field observations of birds. In a previous study we validated the model by testing its predictions against observed patterns of seed dispersal in real landscapes with the same types and spatial configuration of patches as in the model. 3. Here we apply the model more broadly, examining how patch shape influences the probability of seed deposition by birds into patches, how dispersal kernels (distributions of dispersal distances) vary with patch shape and starting location, and how movement of seeds between patches is affected by patch shape. 4. The model predicts that patches with corridors or other narrow extensions receive higher numbers of seeds than patches without corridors or extensions. This pattern is explained by edgefollowing behaviour of birds. Dispersal distances are generally shorter in heterogeneous landscapes (containing patchy habitat) than in homogeneous landscapes, suggesting that patches divert the movement of seed dispersers, ‘holding’ them long enough to increase the probability of seed defecation in the patches. Dispersal kernels for seeds in homogeneous landscapes were smooth, whereas those in heterogenous landscapes were irregular. In both cases, long-distance (> 150 m) dispersal was surprisingly common, usually comprising approximately 50% of all dispersal events. 5. Synthesis . Landscape heterogeneity has a large influence on patterns of long-distance seed dispersal. Our results suggest that long-distance dispersal events can be predicted using spatially explicit modelling to scale-up local movements, placing them in a landscape context. Similar techniques are commonly used by landscape ecologists to model other types of movement; they offer much promise to the study of seed dispersal.
Confined zone dispersion project. Final technical report
NONE
1994-06-01T23:59:59.000Z
This report describes the performance of the confined zone dispersion (CZD) flue gas desulfurization (FGD) system in removing sulfur dioxide (SO{sub 2}) from flue gas in the coal-fired boiler. The CZD-FGD system, installed at Pennsylvania Electric Company`s (Penelec`s) Seward Power Station, was designed to remove 50% of the SO{sub 2} from one-half of Unit No. 5`s flue gas when the boiler is fired with 1.5% sulfur coal. Section 1 discusses the significance of CZD, the purpose of this report, the history of the project, and the role of DOE in the project, describes the project organization, and lists the six design areas involving proprietary information. Section 2 presents project location, objectives, and phases, and discusses the test program. Section 3 explains the process flow diagram, piping and instrumentation diagrams and operating controls, site plan, equipment layouts, and process equipment. Section 4 provides an integrated discussion of all the test results obtained during the test program, backed by tabulations and graphics. Section 5 describes the testing failures and corrective actions taken. Section 6, reliability/availability/maintainability analysis data of major equipment, covers the following systems: atomizing, sootblowing, lime, flue gas, and controls and instrumentation. Section 7 summarizes the capital cost requirements for the Seward CZD demonstration unit and discusses the capital and operating costs of installing the process at plants with various unit capacities. Section 8 discusses plans to continue the CZD demonstration to achieve longer term continuous operation at SO{sub 2} removals of 50%. Section 9 presents the principal findings of the CZD demonstration and recommends additional testing.
Gary D. Bourn; Ford A. Phillips; Ralph E. Harris
2005-12-01T23:59:59.000Z
This document provides results and conclusions for Task 15.0--Detailed Analysis of Air Balance & Conceptual Design of Improved Air Manifolds in the ''Technologies to Enhance the Operation of Existing Natural Gas Compression Infrastructure'' project. SwRI{reg_sign} is conducting this project for DOE in conjunction with Pipeline Research Council International, Gas Machinery Research Council, El Paso Pipeline, Cooper Compression, and Southern Star, under DOE contract number DE-FC26-02NT41646. The objective of Task 15.0 was to investigate the perceived imbalance in airflow between power cylinders in two-stroke integral compressor engines and develop solutions via manifold redesign. The overall project objective is to develop and substantiate methods for operating integral engine/compressors in gas pipeline service, which reduce fuel consumption, increase capacity, and enhance mechanical integrity.
Aeroassisted orbital transfer vehicle guidance performance in the presence of density dispersions
Fitzgerald, Steve Matthew
1988-01-01T23:59:59.000Z
Dispersions Analytic Predictor-Corrector AV, Sensitivity to Step Dispersions Analytic Predictor-Corrector DV, Sensitivity to Spike Dispersions Energy Controller AV, Sensitivity to Step Dispersions 42 44 46 49 49 51 53 56 LIST OF FIGURES...-Corrector AV, Sensitivity to a 10000 foot Duration Step Dispersions . AV, Comparison for 0. 20 Magnitude, 10000 foot Duration, Step Dispersion HPC Bank Angle History for -20% Biased 1962 Standard Atmosphere Page 58 67 67 69 71 71 72 73 75 27...
Performance Analysis of Dispersed Spectrum Cognitive Radio Systems
Mohammad, Muneer
2011-02-22T23:59:59.000Z
Dispersed spectrum cognitive radio systems represent a promising approach to exploit the utilization of spectral resources to full extent. Therefore, the performance analysis of such systems is conducted in this research. The Average symbol error...
Forced-convection, dispersed-flow film boiling
Hynek, Scott Josef
1969-01-01T23:59:59.000Z
This report presents the latest results of an investigation of the characteristics of dispersed flow film boiling. Heat transfer data are presented for vertical upflow of nitrogen in an electrically heated tube, 0.4 in. ...
Dark solitons in dual-core waveguides with dispersive coupling
Kartashov, Yaroslav V; Malomed, Boris A
2015-01-01T23:59:59.000Z
We report on new types of two-component one-dimensional dark solitons (DSs) in a model of a dual-core waveguide with normal group-velocity dispersion and Kerr nonlinearity in both cores, the coupling between which is dispersive too. In the presence of the dispersive coupling, quiescent DSs supported by the zero-frequency background are always gray, being stable with the out-of-phase background, i.e., for opposite signs of the fields in the cores. On the contrary, the background with a nonzero frequency supports quiescent black solitons which may be stable for both out- and in-phase backgrounds, if the dispersive coupling is sufficiently strong. Only DSs supported by the out-of-phase background admit an extension to the case of nonzero phase mismatch between the cores.
Computation of seismic attenuation and dispersion due to ...
masson@localhost.localdomain (masson)
2006-07-08T23:59:59.000Z
Jun 23, 2006 ... used to model the poroelastic response within such materials are those of Biot ... for the seismic attenuation and dispersion in the special case where the ..... lens embedded in shaly sediments or a fracture embedded in a ...
Bayesian Network Analysis of Radiological Dispersal Device Acquisitions
Hundley, Grant Richard
2012-02-14T23:59:59.000Z
inflict moderate human casualties and significant economic damage. The vast availability of radioactive sources and the nearly limitless methods of dispersing them demand an inclusive study of the acquisition pathways for an RDD. A complete network...
Dispersion modeling for prediction of emission factors for cattle feedyards
Parnell, Sarah Elizabeth
1994-01-01T23:59:59.000Z
of state air pollution regulatory agencies will require accurate EPA AP-42 emission factors. A protocol was developed so that accurate emission factors can be determined using both source sampling data and dispersion modeling. In this study, an emission...
Colloidal Manipulation of Nanostructures: Stable Dispersion and Self-assembly
Sun, Dazhi
2013-12-16T23:59:59.000Z
This dissertation work addresses two important aspects of nanotechnology - stable dispersion and self-assembly of colloidal nanostructures. Three distinctly different types of nano-scaled materials have been studied: 0-dimensional ZnO quantum dots...
Mixing and Dispersion in Small-Scale Flow Systems
Nagy, Kevin David
Continuous flow chemistry is being used increasingly; however, without detailed knowledge of reaction engineering, it can be difficult to judge whether dispersion and mixing are important factors on reaction outcome. ...
The integration of dispersed asylum seekers in Glasgow
Rosenberg, Alexandra
This thesis is an analysis of the integration of dispersed asylum seekers in Glasgow. It is a qualitative case study that uses data from participant observation with community groups, interviews with asylum seekers and those involved in service...
Bayesian Network Analysis of Radiological Dispersal Device Acquisitions
Hundley, Grant Richard
2012-02-14T23:59:59.000Z
It remains unlikely that a terrorist organization could produce or procure an actual nuclear weapon. However, the construction of a radiological dispersal device (RDD) from commercially produced radioactive sources and conventional explosives could...
Hair treatment process providing dispersed colors by light diffraction
Lamartine, Bruce Carvell; Orler, E. Bruce; Sutton, Richard Matthew Charles; Song, Shuangqi
2013-12-17T23:59:59.000Z
Hair was coated with polymer-containing fluid and then hot pressed to form a composite of hair and a polymer film imprinted with a nanopattern. Polychromatic light incident on the nanopattern is diffracted into dispersed colored light.
Hair treatment process providing dispersed colors by light diffraction
Lamartine, Bruce Carvell; Orler, E. Bruce; Sutton, Richard Matthew Charles; Song, Shuangqi
2014-11-11T23:59:59.000Z
Hair was coated with polymer-containing fluid and then hot pressed to form a composite of hair and a polymer film imprinted with a nanopattern. Polychromatic light incident on the nanopattern is diffracted into dispersed colored light.
GIS and plume dispersion modeling for population exposure assessment
Archer, Jeffrey Keith
1998-01-01T23:59:59.000Z
that can prove extremely valuable in the modeling process. This data can serve to extend the capabilities of air pollution dispersion modeling from mere estimation of concentrations to comprehensive exposure assessment of neighboring populations (Lowry, et...
Measurement of electron clouds in large accelerators by microwave dispersion
De Santis, Stefano
2008-01-01T23:59:59.000Z
in Large Accelerators by Microwave Dispersion S. De Santis,li.e. , phase shift) of a microwave signal propagating in thethe phase shift of the microwave signal through the electron
Agents of seed dispersal : animal--zoochary / Wind--anemonochory
Lysakowski, Lukasz Kamil, 1974-
2004-01-01T23:59:59.000Z
Agents of seed dispersal is a project designed to address the increase of environmental degradation, which occurs as a result of the perpetual spread of the asphalt and concrete of the contemporary urban situation. Agents ...
EFFLUENT DISPERSION IN THE FRASER RIVER FROM THE
#12;EFFLUENT DISPERSION IN THE FRASER RIVER FROM THE GLENBROOK COMBINED SEWER OVERFLOW AT NEW A wastewater plume delineation study for the Glenbrook combined sewer overflow was conducted in February 1995
RELIABILITY OF WIND POWER FROM DISPERSED SITES: A PRELIMINARY ASSESSMENT
Kahn, E.
2011-01-01T23:59:59.000Z
ON METHODOLOGY: FROM WIND POWER FREQUENCY TO LOSS-OF-LOADJ.P. , "Some Aspects of Wind Power Statistics, " J. of Appl.S£CTION Reliability of Wind Power From Dispersed Sites: A Pr
Dispersion interferometer using modulation amplitudes on LHD (invited)
Akiyama, T., E-mail: takiyama@lhd.nifs.ac.jp; Yasuhara, R.; Kawahata, K. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki-shi, Gifu 509-5292 (Japan); Okajima, S.; Nakayama, K. [Chubu University, Matsumoto-cho, Kasugai-shi, Aichi 487-8501 (Japan)
2014-11-15T23:59:59.000Z
Since a dispersion interferometer is insensitive to mechanical vibrations, a vibration compensation system is not necessary. The CO{sub 2} laser dispersion interferometer with phase modulations on the Large Helical Device utilizes the new phase extraction method which uses modulation amplitudes and can improve a disadvantage of the original dispersion interferometer: measurement errors caused by variations of detected intensities. The phase variation within ±2 × 10{sup 17} m{sup ?3} is obtained without vibration compensation system. The measured line averaged electron density with the dispersion interferometer shows good agreement with that with the existing far infrared laser interferometer. Fringe jump errors in high density ranging up to 1.5 × 10{sup 20} m{sup ?3} can be overcome by a sufficient sampling rate of about 100 kHz.
Quantization of the relativistic fluid in physical phase space on Kaehler manifolds
Holender, L.; Vancea, I. V. [Departamento de Fisica, Universidade Federal Rural do Rio de Janeiro (UFRRJ), Cx. Postal 23851, 23890-000 Seropedica (Brazil); Santos, M. A. [Departamento de Fisica e Quimica, Universidade Federal do Espirito Santo (UFES), Avenida Fernando Ferarri S/N-Goiabeiras, 29060-900 Vitoria (Brazil)
2008-02-15T23:59:59.000Z
We discuss the quantization of a class of relativistic fluid models defined in terms of one real and two complex conjugate potentials with values on a Kaehler manifold, and parametrized by the Kaehler potential K(z,z) and a real number {lambda}. In the Hamiltonian formulation, the canonical conjugate momenta of the potentials are subjected to second-class constraints which allow us to apply the symplectic projector method in order to find the physical degrees of freedom and the physical Hamiltonian. We construct the quantum theory for that class of models by employing the canonical quantization methods. We also show that a semiclassical theory in which the Kaehler and the complex potentials are not quantized has a highly degenerate vacuum. We define and compute the quantum topological number (quantum linking number) operator which has nonvanishing contributions from the Kaehler and complex potentials only. Also, we show that the vacuum and the states formed by tensoring the number operators eigenstates have zero linking number, and show that linear combinations of the tensor product of number operators eigenstates which have the form of entangled states have nonzero linking number.
The landscape of G-structures in eight-manifold compactifications of M-theory
Babalic, Elena Mirela
2015-01-01T23:59:59.000Z
We consider spaces of "virtual" constrained generalized Killing spinors, i.e. spaces of Majorana spinors which correspond to "off-shell" $s$-extended supersymmetry in compactifications of eleven-dimensional supergravity based on eight-manifolds $M$. Such spaces naturally induce two stratifications of $M$, called the chirality and stabilizer stratification. For the case $s=2$, we describe the former using the canonical Whitney stratification of a three-dimensional semi-algebraic set ${\\cal R}$. We also show that the stabilizer stratification coincides with the rank stratification of a cosmooth generalized distribution ${\\cal D}_0$ and describe it explicitly using the Whitney stratification of a four-dimensional semi-algebraic set $\\mathfrak{P}$. The stabilizer groups along the strata are isomorphic with $\\mathrm{SU}(2)$, $\\mathrm{SU}(3)$, $\\mathrm{G}_2$ or $\\mathrm{SU}(4)$, where $\\mathrm{SU(2)}$ corresponds to the open stratum, which is generically non-empty. We also determine the rank stratification of a lar...
The landscape of G-structures in eight-manifold compactifications of M-theory
Elena Mirela Babalic; Calin Iuliu Lazaroiu
2015-05-09T23:59:59.000Z
We consider spaces of "virtual" constrained generalized Killing spinors, i.e. spaces of Majorana spinors which correspond to "off-shell" $s$-extended supersymmetry in compactifications of eleven-dimensional supergravity based on eight-manifolds $M$. Such spaces naturally induce two stratifications of $M$, called the chirality and stabilizer stratification. For the case $s=2$, we describe the former using the canonical Whitney stratification of a three-dimensional semi-algebraic set ${\\cal R}$. We also show that the stabilizer stratification coincides with the rank stratification of a cosmooth generalized distribution ${\\cal D}_0$ and describe it explicitly using the Whitney stratification of a four-dimensional semi-algebraic set $\\mathfrak{P}$. The stabilizer groups along the strata are isomorphic with $\\mathrm{SU}(2)$, $\\mathrm{SU}(3)$, $\\mathrm{G}_2$ or $\\mathrm{SU}(4)$, where $\\mathrm{SU(2)}$ corresponds to the open stratum, which is generically non-empty. We also determine the rank stratification of a larger generalized distribution ${\\cal D}$ which turns out to be integrable in the case of compactifications down to $\\mathrm{AdS}_3$.
Manifold, bus support and coupling arrangement for solid oxide fuel cells
Parry, Gareth W. (East Windsor, CT)
1989-01-01T23:59:59.000Z
Individual, tubular solid oxide fuel cells (SOFCs) are assembled into bundles called a module within a housing, with a plurality of modules arranged end-to-end in a linear, stacked configuration called a string. A common set of piping comprised of a suitable high temperture resistant material (1) provides fuel and air to each module housing, (2) serves as electrically conducting buses, and (3) provides structural support for a string of SOFC modules. The piping thus forms a manfold for directing fuel and air to each module in a string and makes electrical contact with the module's anode and cathode to conduct the DC power generated by the SOFC. The piping also provides structureal support for each individual module and maintains each string of modules as a structurally integral unit for ensuring high strength in a large 3-dimensional array of SOFC modules. Ceramic collars are used to connect fuel and air inlet piping to each of the electrodes in an SOFC module and provide (1) electrical insulation for the current carrying bus bars and gas manifolds, (2) damping for the fuel and air inlet piping, and (3) proper spacing between the fuel and air inlet piping to prevent contact between these tubes and possible damage to the SOFC.
Space-Time as an Orderparameter Manifold in Random Networks and the Emergence of Physical Points
Manfred Requardt
1999-02-11T23:59:59.000Z
In the following we are going to describe how macroscopic space-time is supposed to emerge as an orderparameter manifold or superstructure floating in a stochastic discrete network structure. As in preceeding work (mentioned below), our analysis is based on the working philosophy that both physics and the corresponding mathematics have to be genuinely discrete on the primordial (Planck scale) level. This strategy is concretely implemented in the form of cellular networks and random graphs. One of our main themes is the development of the concept of physical (proto)points as densely entangled subcomplexes of the network and their respective web, establishing something like (proto)causality. It max perhaps be said that certain parts of our programme are realisations of some old and qualitative ideas of Menger and more recent ones sketched by Smolin a couple of years ago. We briefly indicate how this two-story-concept of space-time can be used to encode the (at least in our view) existing non-local aspects of quantum theory without violating macroscopic space-time causality!
Constructing vacuum spacetimes by generating manifolds of revolution around a curve
Vee-Liem Saw
2015-06-23T23:59:59.000Z
We develop a general perturbative analysis on vacuum spacetimes which can be constructed by generating manifolds of revolution around a curve, and apply it to the Schwarzschild metric. The following different perturbations are carried out separately: 1) Non-rotating 2-spheres are added along a plane curve slightly deviated from the "Schwarzschild line"; 2) General non-rotating topological 2-spheres are added along the "Schwarzschild line" 3) Slow-rotating 2-spheres are added along the "Schwarzschild line". For (1), we obtain the first order vacuum solution and show that no higher order solution exists. This linearised vacuum solution turns out however to be just a gauge transformation of the Schwarzschild metric. For (2), we solve the general linearised vacuum equations under several special cases. In particular, there exist linearised vacuum solutions with signature-changing metrics (though these do not correspond to adding topological 2-spheres). For (3), we find that the first order vacuum solution is equivalent to the slowly rotating Kerr metric. This is hence a much simpler and geometrically insightful derivation as compared to the gravitomagnetic one, where this rotating-shells construction is a direct manifestation of the frame-dragging phenomenon. We also show that the full Kerr however, cannot be obtained via adding rotating ellipsoids.
Power-law spatial dispersion from fractional Liouville equation
Tarasov, Vasily E. [Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow 119991 (Russian Federation)] [Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow 119991 (Russian Federation)
2013-10-15T23:59:59.000Z
A microscopic model in the framework of fractional kinetics to describe spatial dispersion of power-law type is suggested. The Liouville equation with the Caputo fractional derivatives is used to obtain the power-law dependence of the absolute permittivity on the wave vector. The fractional differential equations for electrostatic potential in the media with power-law spatial dispersion are derived. The particular solutions of these equations for the electric potential of point charge in this media are considered.
Assessment of gas dispersion in agitated tanks using hydrophones
Sutter, Terry Alan
1986-01-01T23:59:59.000Z
ASSESSMENT OF GAS DISPERSION IN AGITATED TANKS USING HYDROPHONES A Thesis by TERRY ALAN SUTTER Submitted to the Graduate College of Texas ARM University in partial fulfillment of the requirement for the degree of MASTFR OF SCIENCE ofay I...!)sfi Major Subject: Chemical Engineering ASSESSMENT OF GAS DISPERSION IN AGITATED TANKS USING HYDROPHONES A Thesis by TERRY ALAN SUTTER Approved as to style and content by: Gary B. Tatterson (Chairinan of Committee) Gerald L. orrison (Xieniber) C...
Preliminary assessment of regional dispersivity of the Hanford basalts
LaVenue, Arthur Marsh
1985-01-01T23:59:59.000Z
PRELIMINARY ASSESSMENT OF REGIONAL DISPERSIVITY OF THE HANFORD BASALTS A Thesis by ARTHUR MARSH LAVENUE Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... December 1985 Major Subject: Geophysics PRELIMINARY ASSESSMENT OF REGIONAL DISPERSIVITY OF THE HANFORD BASALTS A Thesis by ARTHUR MARSH LAVENUE Approved as to style and content by: ar . Hos ins (Co-Chair of Committee) atric . omenico (Co...
Grant L. Hawkes; James E. O'Brien; Greg Tao
2011-11-01T23:59:59.000Z
A three-dimensional computational fluid dynamics (CFD) electrochemical model has been created to model high-temperature electrolysis cell performance and steam electrolysis in an internally manifolded planar solid oxide electrolysis cell (SOEC) stack. This design is being evaluated at the Idaho National Laboratory for hydrogen production from nuclear power and process heat. Mass, momentum, energy, and species conservation and transport are provided via the core features of the commercial CFD code FLUENT. A solid-oxide fuel cell (SOFC) model adds the electrochemical reactions and loss mechanisms and computation of the electric field throughout the cell. The FLUENT SOFC user-defined subroutine was modified for this work to allow for operation in the SOEC mode. Model results provide detailed profiles of temperature, operating potential, steam-electrode gas composition, oxygen-electrode gas composition, current density and hydrogen production over a range of stack operating conditions. Single-cell and five-cell results will be presented. Flow distribution through both models is discussed. Flow enters from the bottom, distributes through the inlet plenum, flows across the cells, gathers in the outlet plenum and flows downward making an upside-down ''U'' shaped flow pattern. Flow and concentration variations exist downstream of the inlet holes. Predicted mean outlet hydrogen and steam concentrations vary linearly with current density, as expected. Effects of variations in operating temperature, gas flow rate, oxygen-electrode and steam-electrode current density, and contact resistance from the base case are presented. Contour plots of local electrolyte temperature, current density, and Nernst potential indicate the effects of heat transfer, reaction cooling/heating, and change in local gas composition. Results are discussed for using this design in the electrolysis mode. Discussion of thermal neutral voltage, enthalpy of reaction, hydrogen production, cell thermal efficiency, cell electrical efficiency, and Gibbs free energy are discussed and reported herein.
Sex-biased dispersal of adults mediates the evolution of altruism among juveniles
Gardner, Andy
Sex-biased dispersal of adults mediates the evolution of altruism among juveniles Andy Gardner that dispersal does matter if there is a sex difference in dispersal rate, even when the expression of cooperation is not conditional upon the actor's dispersal status or sex. In particular, I show
System and method for detection of dispersed broadband signals
Qian, Shie (Austin, TX); Dunham, Mark E. (Los Alamos, NM)
1999-06-08T23:59:59.000Z
A system and method for detecting the presence of dispersed broadband signals in real time. The present invention utilizes a bank of matched filters for detecting the received dispersed broadband signals. Each matched filter uses a respective robust time template that has been designed to approximate the dispersed broadband signals of interest, and each time template varies across a spectrum of possible dispersed broadband signal time templates. The received dispersed broadband signal x(t) is received by each of the matched filters, and if one or more matches occurs, then the received data is determined to have signal data of interest. This signal data can then be analyzed and/or transmitted to Earth for analysis, as desired. The system and method of the present invention will prove extremely useful in many fields, including satellite communications, plasma physics, and interstellar research. The varying time templates used in the bank of matched filters are determined as follows. The robust time domain template is assumed to take the form w(t)=A(t)cos{2.phi.(t)}. Since the instantaneous frequency f(t) is known to be equal to the derivative of the phase .phi.(t), the trajectory of a joint time-frequency representation of x(t) is used as an approximation of .phi.'(t).
Method of Manufacturing Micro-Disperse Particles of Sodium Borohydride
Kravitz, Stanley H. (Placitas, NM); Hecht, Andrew M. (Sandia Park, NM); Sylwester. Alan P. (Albuquerque, NM); Bell, Nelson S. (Albuquerque, NM)
2008-09-23T23:59:59.000Z
A compact solid source of hydrogen gas, where the gas is generated by contacting water with micro-disperse particles of sodium borohydride in the presence of a catalyst, such as cobalt or ruthenium. The micro-disperse particles can have a substantially uniform diameter of 1-10 microns, and preferably about 3-5 microns. Ruthenium or cobalt catalytic nanoparticles can be incorporated in the micro-disperse particles of sodium borohydride, which allows a rapid and complete reaction to occur without the problems associated with caking and scaling of the surface by the reactant product sodium metaborate. A closed loop water management system can be used to recycle wastewater from a PEM fuel cell to supply water for reacting with the micro-disperse particles of sodium borohydride in a compact hydrogen gas generator. Capillary forces can wick water from a water reservoir into a packed bed of micro-disperse fuel particles, eliminating the need for using an active pump.
System and method for detection of dispersed broadband signals
Qian, S.; Dunham, M.E.
1999-06-08T23:59:59.000Z
A system and method for detecting the presence of dispersed broadband signals in real time are disclosed. The present invention utilizes a bank of matched filters for detecting the received dispersed broadband signals. Each matched filter uses a respective robust time template that has been designed to approximate the dispersed broadband signals of interest, and each time template varies across a spectrum of possible dispersed broadband signal time templates. The received dispersed broadband signal x(t) is received by each of the matched filters, and if one or more matches occurs, then the received data is determined to have signal data of interest. This signal data can then be analyzed and/or transmitted to Earth for analysis, as desired. The system and method of the present invention will prove extremely useful in many fields, including satellite communications, plasma physics, and interstellar research. The varying time templates used in the bank of matched filters are determined as follows. The robust time domain template is assumed to take the form w(t)=A(t)cos[l brace]2[phi](t)[r brace]. Since the instantaneous frequency f(t) is known to be equal to the derivative of the phase [phi](t), the trajectory of a joint time-frequency representation of x(t) is used as an approximation of [phi][prime](t). 10 figs.
The concentration-velocity dispersion relation in galaxy groups
Andreas Faltenbacher; William G. Mathews
2007-06-08T23:59:59.000Z
Based on results from cold dark matter N-body simulations we develop a dynamical model for the evolution of subhaloes within host haloes of galaxy groups. Only subhaloes more massive than 5 times 10^8 M_{sol} at the time of accretion are examined because they are massive enough to possibly host luminous galaxies. As they orbit within a growing host potential the subhaloes are subject to tidal stripping and dynamical friction. We consider groups of equal mass (M_{vir} = 3.9 times 10^{13} M_{sol}) at redshift z=0 but with different concentrations associated with different formation times. We investigate the variation of subhaloe (or satellite galaxy) velocity dispersion with host concentration and/or formation time. In agreement with the Jeans equation the velocity dispersion of subhaloes increases with the host concentration. Between concentrations ~5 and ~20 the subhaloe velocity dispersions increase by ~25 per cent. By applying a simplified tidal disruption criterion, i.e. rejection of all subhaloes with a tidal truncation radius below 3 kpc at z=0, the central velocity dispersion of 'surviving' subhaloes increases substantially for all concentrations. The enhanced central velocity dispersion among surviving subhaloes is caused by a lack of slow tangential motions. Additionally, we present a fitting formula for the velocity anisotropy parameter \\beta(r) which does not depend on concentration if the group-centric distances are scaled by r_s, the characteristic radius of the NFW-profile.
New ceramics containing dispersants for improved fracture toughness
Nevitt, M.V.; Aldred, A.T.; Chan, Sai-Kit
1985-07-01T23:59:59.000Z
The invention is a ceramic composition containing a new class of dispersant for hindering crack propagation by means of one or more energy-dissipative mechanisms. The composition is composed of a ceramic matrix with dispersed particles of a transformation-prone rare-earth niobate, tantalate or mixtures of these with each other and/or with a rare-earth vanadate. The dispersants, having a generic composition tRBO/sub 4/, where R is a rare-earth element, B if Nb or Ta and O is oxygen, are mixed in powder form with a powder of the matrix ceramic and sintered to produce a ceramic form or body. The crack-hindering mechanisms operates to provide improved performance over a wide range of temperature and operating conditions.
Short-range atmospheric dispersion of carbon dioxide
Cortis, A.; Oldenburg, C.M.
2009-11-01T23:59:59.000Z
We present a numerical study aimed at quantifying the effects of concentration-dependent density on the spread of a seeping plume of CO{sub 2} into the atmosphere such as could arise from a leaking geologic carbon sequestration site. Results of numerical models can be used to supplement field monitoring estimates of CO{sub 2} seepage flux by modelling transport and dispersion between the source emission and concentration-measurement points. We focus on modelling CO{sub 2} seepage dispersion over relatively short distances where density effects are likely to be important. We model dense gas dispersion using the steady-state Reynolds-averaged Navier-Stokes equations with density dependence in the gravity term. Results for a two-dimensional system show that a density dependence emerges at higher fluxes than prior estimates. A universal scaling relation is derived that allows estimation of the flux from concentrations measured downwind and vice versa.
Kolmogorov Dispersion for Turbulence in Porous Media: A Conjecture
Bikas K. Chakrabarti
2006-12-26T23:59:59.000Z
We will utilise the self-avoiding walk (SAW) mapping of the vortex line conformations in turbulence to get the Kolmogorov scale dependence of energy dispersion from SAW statistics, and the knowledge of the disordered fractal geometries on the SAW statistics. These will give us the Kolmogorov energy dispersion exponent value for turbulence in porous media in terms of the size exponent for polymers in the same. We argue that the exponent value will be somewhat less than 5/3 for turbulence in porous media.
Fractional Power-Law Spatial Dispersion in Electrodynamics
Tarasov, Vasily E
2015-01-01T23:59:59.000Z
Electric fields in non-local media with power-law spatial dispersion are discussed. Equations involving a fractional Laplacian in the Riesz form that describe the electric fields in such non-local media are studied. The generalizations of Coulomb's law and Debye's screening for power-law non-local media are characterized. We consider simple models with anomalous behavior of plasma-like media with power-law spatial dispersions. The suggested fractional differential models for these plasma-like media are discussed to describe non-local properties of power-law type.
Thomas Laetsch
2013-05-17T23:59:59.000Z
This paper gives a rigorous interpretation of a Feynman path integral on a Riemannian manifold M with non-positive sectional curvature. A $L^2$ Riemannian metric $G_P$ is given on the space of piecewise geodesic paths $H_P(M)$ adapted to the partition $P$ of $[0,1]$, whence a finite-dimensional approximation of Wiener measure is developed. It is proved that, as $mesh(P) \\to 0$, the approximate Wiener measure converges in a $L^1$ sense to the measure $e^{-\\frac{2 + \\sqrt{3}}{20\\sqrt{3}} \\int_0^1 Scal(\\sigma(s)) ds} d\
High-index-core Bragg fibers: dispersion Juan A. Monsoriu
Fernández de Córdoba, Pedro
. P. Yeh, A. Yariv, and E. Marom, "Theory of Bragg fiber," J. Opt. Soc. Am. 68, 1196-1201 (1978). 4. Y. Xu, G.X. Ouyang, R.K. Lee, and A. Yariv, "Asymptotic Matrix Theory of Bragg Fibers," J. LightwaveHigh-index-core Bragg fibers: dispersion properties Juan A. Monsoriu Departamento de Física
Electrical properties of dispersions of graphene in mineral oil
Monteiro, O. R., E-mail: othon.monteiro@bakerhughes.com [Baker Hughes, 14990 Yorktown Plaza Dr., Houston, Texas 77040 (United States)
2014-02-03T23:59:59.000Z
Dispersions of graphene in mineral oil have been prepared and electrical conductivity and permittivity have been measured. The direct current (DC) conductivity of the dispersions depends on the surface characteristics of the graphene platelets and followed a percolation model with a percolation threshold ranging from 0.05 to 0.1?wt. %. The difference in DC conductivities can be attributed to different states of aggregation of the graphene platelets and to the inter-particle electron transfer, which is affected by the surface radicals. The frequency-dependent conductivity (?(?)) and permittivity (?(?)) were also measured. The conductivity of dispersions with particle contents much greater than the percolation threshold remains constant and equal to the DC conductivity at low frequencies ? with and followed a power-law ?(?)???{sup s} dependence at very high frequencies with s?0.9. For dispersions with graphene concentration near the percolation threshold, a third regime was displayed at intermediate frequencies indicative of interfacial polarization consistent with Maxwell-Wagner effect typically observed in mixtures of two (or more) phases with very distinct electrical and dielectric properties.
THE EFFECT OF TRANSVERSE MIXING ON TRACER DISPERSION
Stanford University
Hardware Data Acquisition And Analysis Software Experimental Procedure Analysis Procedure Results: Taylor. The theoretical response for linear Taylor dispersion was matched to the data to determine the non-linear Of Tracer Valve Constant-pressure Reservoir Design Schematic Drawing Of Electrode Circuit Results: Run 16
Heavy tailed K distributions imply a fractional advection dispersion equation
Meerschaert, Mark M.
Dispersion Equation (FADE) to model contaminant transport in porous media. This equation characterizes, and Particle Jumps Equations of contaminant transport in porous media are based on assumptions about hydraulic governing groundwater flow (e.g., Freeze and Cherry, 1979): h K v - = (1) where v is average velocity
Optimization of Dispersed Energy Supply -Stochastic Programming with Recombining
Römisch, Werner
1 Optimization of Dispersed Energy Supply - Stochastic Programming with Recombining Scenario Trees of the most important fields within energy supply, has two main characteristics: on the one hand supply energy supply has to be taken into account. Things are complicated further through daily, weekly
Combined dispersive/interference spectroscopy for producing a vector spectrum
Erskine, David J. (Oakland, CA)
2002-01-01T23:59:59.000Z
A method of measuring the spectral properties of broadband waves that combines interferometry with a wavelength disperser having many spectral channels to produce a fringing spectrum. Spectral mapping, Doppler shifts, metrology of angles, distances and secondary effects such as temperature, pressure, and acceleration which change an interferometer cavity length can be measured accurately by a compact instrument using broadband illumination. Broadband illumination avoids the fringe skip ambiguities of monochromatic waves. The interferometer provides arbitrarily high spectral resolution, simple instrument response, compactness, low cost, high field of view and high efficiency. The inclusion of a disperser increases fringe visibility and signal to noise ratio over an interferometer used alone for broadband waves. The fringing spectrum is represented as a wavelength dependent 2-d vector, which describes the fringe amplitude and phase. Vector mathematics such as generalized dot products rapidly computes average broadband phase shifts to high accuracy. A Moire effect between the interferometer's sinusoidal transmission and the illumination heterodynes high resolution spectral detail to low spectral detail, allowing the use of a low resolution disperser. Multiple parallel interferometer cavities of fixed delay allow the instantaneous mapping of a spectrum, with an instrument more compact for the same spectral resolution than a conventional dispersive spectrometer, and not requiring a scanning delay.
Weakly dispersive hydraulic flows in a contraction --Nonlinear stability analysis
Ee, Bernard Kuowei
Weakly dispersive hydraulic flows in a contraction -- Nonlinear stability analysis Bernard K. Ee hydraulic solutions of the forced Korteweg de-Vries equation is investigated here. For numerical convenience is destabilized by a hydraulic instability in which superexponential growth occurs prior to satura- tion
Diffusion and Dispersion Characterization of a Numerical Tsunami Model
Tolkova, Elena
Diffusion and Dispersion Characterization of a Numerical Tsunami Model David Burwell, Elena Tolkova and Arun Chawla February 6, 2007 1 Introduction Method Of Splitting Tsunami (MOST) is a depth averaged long wave tsunami inundation model that was originally developed by Titov and Synolakis (1995) for 1D
Analysis of Tracer Dispersion During a Prescribed Forest Burn
Collins, Gary S.
. Additionally, a sulfur hexafluoride (SF6) tracer dispersion test was conducted by releasing SF6 from a line source within the burn and measuring SF6 concentrations at the supertower. Supertower Instrumentation (TGAPS) connected to a CO2 closed path Licor LI-6262 and a SF6 detector (7 inlet locations) ·Cambell CSAT
Data Assimilation in Variable Dimension Dispersion Models using Particle Filters
Singh, Tarunraj
Data Assimilation in Variable Dimension Dispersion Models using Particle Filters K. V. Umamaheswara at Buffalo Buffalo, NY, U.S.A. peter@buffalo.edu Abstract-- Data assimilation in the context of puff based models usually lead to high dimensional space-gridded state space models. In the case of puff based
Pulse confinement in optical fibers with random dispersion
Gabitov, Ildar
Pulse confinement in optical fibers with random dispersion M. Chertkov , I. Gabitov, and J. Moeser and eventually destroys all initially ultra-short pulses. However, under the con- straint that the integral- periodically along the fiber, the dynamics of the pulse propagation changes dramatically. For the case
Effect of Dispersant on Asphaltene Suspension Dynamics: Aggregation and Sedimentation
Firoozabadi, Abbas
processes, most involving scat- tering, either dynamic light scattering, static light scattering, or neutron on this aggregation behavior through the use of dynamic light scattering, showing that both the amount of dispersant asphaltene suspensions. The light scattering results match well with those obtained through the macroscopic
ORIGINAL ARTICLE Dispersal in microbes: fungi in indoor air are
combined with selective pressures imposed by the occupants' behaviors and the building itself. We set out). Moreover, room and occupant behavior had no detectable effect on the fungi found in indoor air is a complex system that is thought to depend on dispersal from the outdoor biome and the occupants' microbiome
NOAA Technical Report NMFS SSRF-705 Migration and Dispersion of
#12;#12;NOAA Technical Report NMFS SSRF-705 Migration and Dispersion of Tagged American Lobsters of recoveries Definition of lobster maturity Migration ver u di persion Compo ite tation resumes Composite Depth distribution at recapture verage monthly bottom temperatures oncJu ions ~ummary Acknowledgment
Model hydrocracking reactions over monometallic and bimetallic dispersed catalysts
Schmidt, E.; Song, C. [Penn State Univ., University Park, PA (United States)
1994-12-31T23:59:59.000Z
Coal liquefaction involves the cleavage of methylene and dimethylene bridges connecting polycyclic aromatic units. The selected compound for model reactions is 4-(1-naphthylmethyl)bibenzyl (NMBB). This work describes the synthesis and screening of several metallic complex precursors as dispersed catalysts for hydrocracking of NMBB.
Permeability and Dispersion Coefficients in Rocks with Fracture Network - 12140
Lee, C.K.; Htway, M.Z. [Handong Global University, 3 Namsong-ri, Heunghae-eub, Buk-gu, Pohang, Kyungbuk, 791-708 (Korea, Republic of); Yim, S.P. [Korea Atomic Energy Research Institute, P.O.Box 150, Yusong, Daejon, 305-600 (Korea, Republic of)
2012-07-01T23:59:59.000Z
Fluid flow and solute transport are considered for a rock medium with a fracture network with regard to the effective permeability and the dispersion coefficients. To investigate the effects of individual fractures a three-fracture system is chosen in which two are parallel and the third one connects the two at different angles. Specifically the micro-cell boundary-value problems(defined through multiple scale analysis) are solved numerically by using finite elements to calculate the permeability and dispersion coefficients. It is shown that the permeability depends significantly on the pattern of the fracture distribution and the dispersion coefficient is influenced by both the externally imposed pressure gradient (which also reflects the flow field) and the direction of the gradient of solute concentration on the macro-scale. From the calculations of the permeability and dispersion coefficients for solute in a rock medium with a fracture network the following conclusions are drawn. 1. The permeability of fractured medium depends on the primary orientation of the fracture network and is influenced by the connecting fractures in the medium. 2. The cross permeability, e.g., permeability in the direction normal to the direction of the external pressure gradient is rather insensitive to the orientation of the fracture network. 3. Calculation of permeability is most efficiently achieved with optimal discretization across individual fractures and is rather insensitive to the discretization along the fracture.. 4. The longitudinal dispersion coefficient Dxx of a fractured medium depends on both the macro-scale concentration gradient and the direction of the flow (pressure gradient). Hence both features must be considered when investigating solute transport in a fractured medium. (authors)
Ohbuchi, Ryutarou
Takahiko Furuya and Ryutarou Ohbuchi, Diffusion-on-Manifold Aggregation of Local Features for Shape-based 3D Model Retrieval, accepted as oral paper, Proc. ACM International Conference on Multimedia Information Retrieval (ICMR) 2015, Shanghai, China. 1 Diffusion-on-Manifold Aggregation of Local Features
Paris-Sud XI, Université de
1 Effect of dispersed crude oil exposure upon the aerobic metabolic scope in juvenile golden grey; CD: Chemically Dispersed oil using dispersant; D: Dispersant solution; MD: Mechanically Dispersed oil technique to oil spill. Through an experimental approach with juveniles of Liza aurata, the toxicity of five
Heat transfer to impacting drops and post critical heat flux dispersed flow
Kendall, Gail E.
1978-01-01T23:59:59.000Z
Heat transfer to drops impacting on a hot surface is examined in context of dispersions of flowing, boiling fluids. The liquid contribution to heat transfer from a hot tube to a two-phase dispersion is formulated in terms ...
Color dispersion and Milky-Way-like reddening among type Ia supernovae...
Office of Scientific and Technical Information (OSTI)
Color dispersion and Milky-Way-like reddening among type Ia supernovae Citation Details In-Document Search Title: Color dispersion and Milky-Way-like reddening among type Ia...
Energy Dispersed Large Data Wave Maps in 2 + 1 Dimensions
Sterbenz, Jacob; Tataru, Daniel
2010-01-01T23:59:59.000Z
of Finite S Norm Wave-Maps and Energy Dispersion 10.1renormalization of large energy wave maps. In: Journées “of Finite S Norm Wave-Maps and Energy Dispersion In this
Review of the ENSR Report Titled "Update 1 to: A Dispersion Modeling...
Office of Environmental Management (EM)
"Update 1 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant" Review of the ENSR Report Titled "Update 1 to: A Dispersion Modeling Analysis of...
Highly dispersed carbon nanotubes in organic media for polymer:fullerene photovoltaic devices
Hong, Soon Hyung
Highly dispersed carbon nanotubes in organic media for polymer:fullerene photovoltaic devices Gwang photovoltaic device are fabricated using homogeneously dispersed carbon nanotubes (CNTs) in a polymer. All rights reserved. 1. Introduction Organic photovoltaic (OPV) materials promise the production
Development of a GIS Based Dust Dispersion Modeling System.
Rutz, Frederick C.; Hoopes, Bonnie L.; Crandall, Duard W.; Allwine, K Jerry
2004-08-12T23:59:59.000Z
With residential areas moving closer to military training sites, the effects upon the environment and neighboring civilians due to dust generated by training exercises has become a growing concern. Under a project supported by the Strategic Environmental Research and Development Program (SERDP) of the Department of Defense, a custom application named DUSTRAN is currently under development that integrates a system of EPA atmospheric dispersion models with the ArcGIS application environment in order to simulate the dust dispersion generated by a planned training maneuver. This integration between modeling system and GIS application allows for the use of real world geospatial data such as terrain, land-use, and domain size as input by the modeling system. Output generated by the modeling system, such as concentration and deposition plumes, can then be displayed upon accurate maps representing the training site. This paper discusses the development of this integration between modeling system and Arc GIS application.
A fractional dispersion model for overland solute transport
Deng, Zhi-Qiang; de Lima, M. Isabel P.; Singh, Vijay P.; de Lima, Jo??o L. M. P.
2006-03-18T23:59:59.000Z
s m @ FC01 C @x FC01 C0 1C0s m ?? @ FC01 C @x FC01 C20C21 C0D t s t @ FC01 C @x FC01 C0 1C0s t ?? @ FC01 C @x FC01 C20C21 C0K @ FC01 C @x FC01 ?2b? where D t is the turbulent diffusion coefficient; K is the longitudinal dispersion coefficient; F is a... two terms as J ?C0K @ FC01 C @x FC01 ?2c? The minus sign in equation (2c) means that dispersion is down the concentration gradient. The longitudinal disper- sion coefficient K carries the dimension of [L F /s] and it is a variable in principle. A...
CFD Simulations of Joint Urban Atmospheric Dispersion Field Study
Lee, R; Humphreys III, T; Chan, S
2004-06-17T23:59:59.000Z
The application of Computational Fluid Dynamics (CFD) to the understanding of urban wind flow and dispersion processes has gained increasing attention over recent years. While many of the simpler dispersion models are based on a set of prescribed meteorology to calculate dispersion, the CFD approach has the ability of coupling the wind field to dispersion processes. This has distinct advantages when very detailed results are required, such as for the case where the releases occur around buildings and within urban areas. CFD also has great flexibility as a testbed for turbulence models, which has important implications for atmospheric dispersion problems. In the spring of 2003, a series of dispersion field experiments (Joint Urban 2003) were conducted at Oklahoma City (Allwine, et. al, 2004). These experiments were complimentary to the URBAN 2000 field studies at Salt Lake City (Shinn, et. al, 2000) in that they will provide a second set of comprehensive field data for evaluation of CFD as well as for other dispersion models. In contrast to the URBAN 2000 experiments that were conducted entirely at night, these new field studies took place during both daytime and nighttime thus including the possibility of convective as well as stable atmospheric conditions. Initially several CFD modeling studies were performed to provide guidance for the experimental team in the selection of release sites and in the deployment of wind and concentration sensors. Also, while meteorological and concentration measurements were taken over the greater Oklahoma City urban area, our CFD calculations were focused on the near field of the release point. The proximity of the source to a large commercial building and to the neighboring buildings several of which have multistories, present a significant challenge even for CFD calculations involving grid resolutions as fine as 1 meter. A total of 10 Intensive Observations Periods (IOP's) were conducted within the 2003 field experiments. SF6 releases in the form of puffs or continuous sources were disseminated over 6 daytime and 4 nighttime episodes. Many wind and concentration sensors were used to provide wind and SF6 data over both long and short time-averaging periods. In addition to the usual near surface measurements, data depicting vertical profiles of wind and concentrations adjacent to the outside walls of several buildings were also taken. Also of interest were observations of the trajectory of balloons that were deployed close to the tracer release area. Many of the balloons released exhibit extremely quick ascents up from ground level to the top of buildings, thus implying highly convective conditions. In this paper we will present some simulations that were performed during the planning of the field experiments. The calculations were based on two possible release sites at the intersections of Sheridan and Robinson, and Broadway and Sheridan. These results provided initial information on flow and dispersion patterns, which could be used to guide optimal placement of sensors at appropriate locations. We will also discuss results of more recent simulations for several releases in which reliable data is available. These simulations will be compared with the near field data taken from the wind sensors as well as the time-averaged data from the concentration sensors. Among the other topics discussed are initial and boundary conditions used in the simulations, adaptation of building GIS data for CFD modeling and analysis of field data.
GIS and plume dispersion modeling for population exposure assessment
Archer, Jeffrey Keith
1998-01-01T23:59:59.000Z
. CHAPTER vll I INTRODUCTION. II REVIEW OF PREVIOUS RESEARCH III JUSTIFICATION AND OBJECTIVES. 3. 1 Justification. 3. 2 Project Objectives. IV METHODOLOGY . . . 15 . 15 . . . 17 . . 19 4. 1 The Study Site. 4. 2 Pollution Plume Dispersion Data.... 4. 3 Spatial and Demographic Data. 4. 4 Data Integration. V RESULTS. . . . . 19 . . . 21 . . . 36 . . 45 VI CONCLUSIONS. . . . . 60 6. 1 Conclusions, 6. 2 Room for Improvement. REFERENCES. APPENDIX A: Charts and Data Sheets. 60 . . . 61...
Estimating dispersion from a tornado vortex and mesocyclone
Weber, A.H.; Hunter, C.H.
1996-06-01T23:59:59.000Z
Atmospheric dispersion modeling is required to ensure that a postulated breach in radionuclide storage containers at the Savannah River Site (SRS) from a tornado strike of Fujita-scale intensity F2 or higher will not result in an unacceptable dose to individuals. Fujita-scale tornado descriptions are included in Appendix A of this report. Dispersion models previously used at SRS for estimating dispersion following a tornado strike were developed by D.W. Pepper in 1975 (DP-1387, Dispersion of Small Particles) and H.R. Haynes and D.W. Taylor in 1983 (DPST-82-982, Estimating Doses from Tornado Winds). Research conducted in 1983 on the formation and evolution of tornadic thunderstorms has lead to a more complete understanding of the tornado vortex and associated persistent updraft and downdraft regions within the parent thunderstorm. To ensure that appropriate, contemporary methods are used for safety analysis, the Pepper model and the Haynes and Taylor model were evaluated with respect to current knowledge of circulations within tornadic thunderstorms. Pepper`s model is complex numerically but contains most of the desired physical parameterizations. Haynes and Taylor`s model is used with the Puff-Plume model (an emergency response model on the Weather INformation and Display System at SRS) and has provisions for radionuclide deposition and rainout. Haynes and Taylor assumed heavy rain following the tornado for a period of ten minutes, followed by a lighter rain for another ten minutes, then no rain for the period when the material is transported to 100 km downwind. However, neither model incorporates the effects of a nearby thunderstorm downdraft.
Hanford atmospheric dispersion data: 1960 through June 1967
Nickola, P.W.; Ramsdell, J.V.; Glantz, C.S.; Kerns, R.E.
1983-11-01T23:59:59.000Z
This volume presents dispersion and supporting meteorological data from experiments conducted over relatively flat terrain at Hanford, Washington from January 1960 through June 1967. The nature of the experiments, the sampling grids, and the tracer techniques used are described in the narrative portion of the document. Appendices contain the time-integrated concentrations for samplers within the plumes, summaries of the concentration distributions across the plumes, and wind and temperature profile data for each release period. 18 references, 7 figures, 3 tables.
A dispersion curve study of dredged spoil basin inlets
Male, Robert
1974-01-01T23:59:59.000Z
13 19 IV. PROCEDURES AND TECHNIOUHS Test Procenures. Interpretation of Dispersion Curves. Data Analysis, 26 26 28 37 V. EXPERIMENTAL RESULTS. VI. DISCUSSION. The Model as a Settling Tank Relationship to Dredging Practice. 58 58 70 VII... all the spoil must be confined. The additional costs to be incurred in that region over ten years vary from $2. 62 million to $12. 87 million according to the confinement scheme. In the USA, most of the dredging projects are under the con- trol...
Global regularity of critical Schrödinger maps: subthreshold dispersed energy
Paul Smith
2012-12-19T23:59:59.000Z
We consider the energy-critical Schroedinger map initial value problem with smooth initial data from R^2 into the sphere S^2. Given sufficiently energy-dispersed data with subthreshold energy, we prove that the system admits a unique global smooth solution. This improves earlier analogous conditional results. The key behind this improvement lies in exploiting estimates on the commutator of the Schroedinger map and harmonic map heat flows.
Atmospheric dispersion estimates in the vicinity of buildings
Ramsdell, J.V. Jr.; Fosmire, C.J.
1995-01-01T23:59:59.000Z
A model describing atmospheric dispersion in the vicinity of buildings was developed for the U.S. Nuclear Regulatory Commission (NRC) in the late 1980s. That model has recently undergone additional peer review. The reviewers identified four areas of concern related to the model and its application. This report describes revisions to the model in response to the reviewers concerns. Model revision involved incorporation of explicit treatment of enhanced dispersion at low wind speeds in addition to explicit treatment of enhanced dispersion at high speeds resulting from building wakes. Model parameters are evaluated from turbulence data. Experimental diffusion data from seven reactor sites are used for model evaluation. Compared with models recommended in current NRC guidance to licensees, the revised model is less biased and shows more predictive skill. The revised model is also compared with two non-Gaussian models developed to estimate maximum concentrations in building wakes. The revised model concentration predictions are nearly the same as the predictions of the non-Gaussian models. On the basis of these comparisons of the revised model concentration predictions with experimental data and the predictions of other models, the revised model is found to be an appropriate model for estimating concentrations in the vicinity of buildings.
HUNTING FOR YOUNG DISPERSING STAR CLUSTERS IN IC 2574
Pellerin, Anne [Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843-4242 (United States); Meyer, Martin M. [International Centre for Radio Astronomy Research, University of Western Australia, 35 Stirling Highway, CRAWLEY WA 6009 (Australia); Calzetti, Daniella [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Harris, Jason, E-mail: apellerin@mta.ca, E-mail: martin.meyer@uwa.edu.au, E-mail: calzetti@astro.umass.edu, E-mail: jharris@30doradus.org [Illumina, Inc., 25861 Industrial Blvd, Hayward, CA 94545 (United States)
2012-12-01T23:59:59.000Z
Dissolving stellar groups are very difficult to detect using traditional surface photometry techniques. We have developed a method to find and characterize non-compact stellar systems in galaxies where the young stellar population can be spatially resolved. By carrying out photometry on individual stars, we are able to separate the luminous blue stellar population from the star field background. The locations of these stars are used to identify groups by applying the HOP algorithm, which are then characterized using color-magnitude and stellar density radial profiles to estimate age, size, density, and shape. We test the method on Hubble Space Telescope Advanced Camera for Surveys archival images of IC 2574 and find 75 dispersed stellar groups. Of these, 20 highly dispersed groups are good candidates for dissolving systems. We find few compact systems with evidence of dissolution, potentially indicating that star formation in this galaxy occurs mostly in unbound clusters or groups. These systems indicate that the dispersion rate of groups and clusters in IC 2574 is at most 0.45 pc Myr{sup -1}. The location of the groups found with HOP correlate well with H I contour map features. However, they do not coincide with H I holes, suggesting that those holes were not created by star-forming regions.
A Dispersive Treatment of $K_{\\ell4}$ Decays
Colangelo, Gilberto; Stoffer, Peter
2015-01-01T23:59:59.000Z
$K_{\\ell4}$ decays offer several reasons of interest: they allow an accurate measurement of $\\pi\\pi$-scattering lengths; they provide the best source for the determination of some low-energy constants of ChPT; one form factor is directly related to the chiral anomaly, which can be measured here. We present a dispersive treatment of $K_{\\ell4}$ decays that provides a resummation of $\\pi\\pi$- and $K\\pi$-rescattering effects. The free parameters of the dispersion relation are fitted to the data of the high-statistics experiments E865 and NA48/2. The matching to ChPT at NLO and NNLO enables us to determine the LECs $L_1^r$, $L_2^r$ and $L_3^r$. With recently published data from NA48/2, the LEC $L_9^r$ can be determined as well. In contrast to a pure chiral treatment, the dispersion relation describes the observed curvature of one of the form factors, which we understand as a rescattering effect beyond NNLO.
A Dispersive Treatment of $K_{\\ell4}$ Decays
Gilberto Colangelo; Emilie Passemar; Peter Stoffer
2015-01-22T23:59:59.000Z
$K_{\\ell4}$ decays offer several reasons of interest: they allow an accurate measurement of $\\pi\\pi$-scattering lengths; they provide the best source for the determination of some low-energy constants of ChPT; one form factor is directly related to the chiral anomaly, which can be measured here. We present a dispersive treatment of $K_{\\ell4}$ decays that provides a resummation of $\\pi\\pi$- and $K\\pi$-rescattering effects. The free parameters of the dispersion relation are fitted to the data of the high-statistics experiments E865 and NA48/2. The matching to ChPT at NLO and NNLO enables us to determine the LECs $L_1^r$, $L_2^r$ and $L_3^r$. With recently published data from NA48/2, the LEC $L_9^r$ can be determined as well. In contrast to a pure chiral treatment, the dispersion relation describes the observed curvature of one of the form factors, which we understand as a rescattering effect beyond NNLO.
1-D profiling using highly dispersive guided waves
Volker, Arno; Zon, Tim van [TNO, Stieltjesweg 1, P.O. box 155 2600 AD Delft (Netherlands)
2014-02-18T23:59:59.000Z
Corrosion is one of the industries major issues regarding the integrity of assets. Currently, inspections are conducted at regular intervals to ensure a sufficient integrity level of these assets. Cost reduction while maintaining a high level of reliability and safety of installations is a major challenge. There are many situations where the actual defect location is not accessible, e.g., a pipe support or a partially buried pipe. Guided wave tomography has been developed to reconstruct the wall thickness of steel pipes. In case of bottom of the line corrosion, i.e., a single corrosion pit, a simpler approach may be followed. Data is collected in a pitch-catch configuration at the 12 o'clock position using highly dispersive guided waves. After dispersion correction the data collapses to a short pulse, any residual dispersion indicates wall loss. The phase spectrum is used to invert for the wall thickness profile in the circumferential direction, assuming a Gaussian defect profile. The approach is evaluated on numerically simulated and on measured data. The method is intended for rapid, semi-quantitative screening of pipes.
Oil and Air Dispersion in a Simulated Fermentation Broth as a Function of Mycelial Morphology
Sridhar, Srinivas
Oil and Air Dispersion in a Simulated Fermentation Broth as a Function of Mycelial Morphology morphology (Trichoderma harzianum) on castor oil and air dispersion. Measurements of oil drops and air to the system. Larger oil drop sizes were obtained with dispersed mycelia than with pellets, as a result
Participatory Sensing in Commerce: Using Mobile Camera Phones to Track Market Price Dispersion
Bulusu, Nirupama
Participatory Sensing in Commerce: Using Mobile Camera Phones to Track Market Price Dispersion In economics, price dispersion refers to the price difference of a homogeneous good across different vendors. According to [1] "The empirical evidence suggests that price dispersion in both online and offline markets
Creation of the model and implementation of the simulation of dispersion of air pollution in urban
Bargiela, Andrzej
Creation of the model and implementation of the simulation of dispersion of air pollution in urban..............................................................................................................1 1.2. Types of models of dispersion of air pollution was creation of the mathematical model and application of the simulation of dispersion of vehicular air
Fine, Dana S., E-mail: dfine@umassd.edu [Mathematics Department, University of Massachusetts Dartmouth, North Dartmouth, Massachusetts 02747 (United States); Sawin, Stephen, E-mail: ssawin@fairfield.edu [Mathematics Department, Fairfield University, Fairfield, Connecticut 06824 (United States)
2014-06-15T23:59:59.000Z
Following Feynman's prescription for constructing a path integral representation of the propagator of a quantum theory, a short-time approximation to the propagator for imaginary-time, N = 1 supersymmetric quantum mechanics on a compact, even-dimensional Riemannian manifold is constructed. The path integral is interpreted as the limit of products, determined by a partition of a finite time interval, of this approximate propagator. The limit under refinements of the partition is shown to converge uniformly to the heat kernel for the Laplace-de Rham operator on forms. A version of the steepest descent approximation to the path integral is obtained, and shown to give the expected short-time behavior of the supertrace of the heat kernel.
Yang Xuefeng; Cui Jian; Zhang Yuan [School of Mathematical Sciences, Dalian University of Technology, Dalian 116024 (China); Liu Yue [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)
2012-07-15T23:59:59.000Z
The dispersion relations of the externally and thermally (naturally) excited dust lattice modes (both longitudinal and transverse) in two-dimensional Debye-Yukawa complex plasma crystals are investigated. The dispersion relations are calculated numerically by taking the neutral gas damping effects into account and the numerical results are in agreement with the experimental data given by Nunomura et al.[Phys. Rev. E 65, 066402 (2002)]. It is found that for the mode excited by an external disturbance with a real frequency, the dispersion properties are changed at a critical frequency near where the group velocity of the mode goes to zero. Therefore, the high frequency branch with negative dispersion cannot be reached. In contrast, for the thermally excited mode, the dispersion curve can extend all the way to the negative dispersion region, while a 'cut-off' wave number exists at the long wavelength end of the dispersion in the transverse mode.
Dispersion modeling of ground-level area sources of particulate
Fritz, Bradley Keith
1998-01-01T23:59:59.000Z
, as shown by Equation 3. f(z) = exp ?, + exp? Y This curve represents the distribution of pollutant in the y-z plane. At any point y, a fraction of the total area of the curve [1] is determined The width of the curve depends on o?, a dispersion... the terminal settling velocity. Equation 6 and 7 are used. C p p dp g 18' where: t-o. ss, 'I C = 1+ ? 2. 514+ 0. 8e d (Eq. 6) (Eq 7) V, = Terminal Settling Velocity [m/s] C = Cunningham's Correction Factor [1/1] p, = density; 1500 [kg/m'] ) = gas...
Electrophoresis of colloidal dispersions in the low-salt regime
Vladimir Lobaskin; Burkhard Duenweg; Martin Medebach; Thomas Palberg; Christian Holm
2006-12-15T23:59:59.000Z
We study the electrophoretic mobility of spherical charged colloids in a low-salt suspension as a function of the colloidal concentration. Using an effective particle charge and a reduced screening parameter, we map the data for systems with different particle charges and sizes, including numerical simulation data with full electrostatics and hydrodynamics and experimental data for latex dispersions, on a single master curve. We observe two different volume fraction-dependent regimes for the electrophoretic mobility that can be explained in terms of the static properties of the ionic double layer.
Anomalous magnetic moment of the muon in a dispersive approach
Vladyslav Pauk; Marc Vanderhaeghen
2014-09-03T23:59:59.000Z
We present a new general dispersive formalism for evaluating the hadronic light-by-light scattering contribution to the anomalous magnetic moment of the muon. In the suggested approach, this correction is related to the imaginary part of the muon's electromagnetic vertex function. The latter may be directly related to measurable hadronic processes by means of unitarity and analyticity. As a test we apply the introduced formalism to the case of meson pole exchanges and find agreement with the direct two-loop calculation.
Electromagnetic energy dispersion in a 5D universe
Hartnett, John G. [School of Physics, University of Western Australia, 35 Stirling Hwy, Crawley 6009 WA Australia (Australia)
2010-06-15T23:59:59.000Z
Electromagnetism is analyzed in a 5D expanding universe. Compared to the usual 4D description of electrodynamics it can be viewed as adding effective charge and current densities to the universe that are static in time. These lead to effective polarization and magnetization of the vacuum, which is most significant at high redshift. Electromagnetic waves propagate but group and phase velocities are dispersive. This introduces a new energy scale to the cosmos. And as a result electromagnetic waves propagate with superluminal speeds but no energy is transmitted faster than the canonical speed of light c.
Dispersion toughened ceramic composites and method for making same
Stinton, D.P.; Lackey, W.J.; Lauf, R.J.
1984-09-28T23:59:59.000Z
Ceramic composites exhibiting increased fracture toughness are produced by the simultaneous codeposition of silicon carbide and titanium disilicide by chemical vapor deposition. A mixture of hydrogen, methyltrichlorosilane and titanium tetrachloride is introduced into a furnace containing a substrate such as graphite or silicon carbide. The thermal decomposition of the methyltrichlorosilane provides a silicon carbide matrix phase and the decomposition of the titanium tetrachloride provides a uniformly dispersed second phase of the intermetallic titanium disilicide within the matrix phase. The fracture toughness of the ceramic composite is in the range of about 6.5 to 7.0 MPa..sqrt..m which represents a significant increase over that of silicon carbide.
Dispersion toughened ceramic composites and method for making same
Stinton, David P. (Knoxville, TN); Lackey, Walter J. (Oak Ridge, TN); Lauf, Robert J. (Oak Ridge, TN)
1986-01-01T23:59:59.000Z
Ceramic composites exhibiting increased fracture toughness are produced by the simultaneous codeposition of silicon carbide and titanium disilicide by chemical vapor deposition. A mixture of hydrogen, methyltrichlorosilane and titanium tetrachloride is introduced into a furnace containing a substrate such as graphite or silicon carbide. The thermal decomposition of the methyltrichlorosilane provides a silicon carbide matrix phase and the decomposition of the titanium tetrachloride provides a uniformly dispersed second phase of the intermetallic titanium disilicide within the matrix phase. The fracture toughness of the ceramic composite is in the range of about 6.5 to 7.0 MPa.sqroot.m which represents a significant increase over that of silicon carbide.
Mathematical modeling of air pollution emissions and dispersion near intersections
Nelli, James Patrick
1982-01-01T23:59:59.000Z
Administration (PHWA) RFP No. DTPB61-80-8-00340 under Texas Transportation Institute (TTI) Project So. 2-8-81-541 and is intended to provide an improved perspective in the analysis of highway air pollution hot spots. The study was directed toward... of the free-flowing traffic. Since the dispersion nomographs were derived for a receptor height of 1. 8 metres (5. 9 ft), additional nomographs are presented relating roadway/receptor separa- tion and actual receptor height to a height correction factor, z...
RADIONUCLIDE DISPERSION RATES BY AEOLIAN, FLUVIAL, AND POROUS MEDIA TRANSPORT
J. Walton; P. Goodell; C. Brashears; D. French; A. Kelts
2005-07-11T23:59:59.000Z
Radionuclide transport was measured from high grade uranium ore boulders near the Nopal I Site, Chihuahua, Mexico. High grade uranium ore boulders were left behind after removal of a uranium ore stockpile at the Prior High Grade Stockpile (PHGS). During the 25 years when the boulder was present, radionuclides were released and transported by sheetflow during precipitation events, wind blown resuspension, and infiltration into the unsaturated zone. In this study, one of the boulders was removed, followed by grid sampling of the surrounding area. Measured gamma radiation levels in three dimensions were used to derive separate dispersion rates by the three transport mechanisms.
Dispersive approach to hadronic light-by-light scattering
Gilberto Colangelo; Martin Hoferichter; Massimiliano Procura; Peter Stoffer
2014-08-22T23:59:59.000Z
Based on dispersion theory, we present a formalism for a model-independent evaluation of the hadronic light-by-light contribution to the anomalous magnetic moment of the muon. In particular, we comment on the definition of the pion pole in this framework and provide a master formula that relates the effect from pi pi intermediate states to the partial waves for the process gamma^* gamma^* --> pi pi. All contributions are expressed in terms of on-shell form factors and scattering amplitudes, and as such amenable to an experimental determination.
Structure of graphene oxide dispersed with ZnO nanoparticles
Yadav, Rishikesh, E-mail: rishikesh.yadav62@gmail.com; Pandey, Devendra K., E-mail: devendrakphy@gmail.com [School of Nanotechnology, Rajiv Gandhi Proudyogiki Vishwavidalaya, Bhopal, M.P. (India); Khare, P. S., E-mail: purnimaswarup@hotmail.com [Department of Physics, Rajiv Gandhi Proudyogiki Vishwavidalaya, Bhopal M.P. (India)
2014-10-15T23:59:59.000Z
Graphene has been proposed as a promising two-dimensional nanomaterial with outstanding electronic, optical, thermal and mechanical properties for many applications. In present work a process of dispersion of graphene oxide with ZnO nanoparticles in ethanol solution with different pH values, have been studied. Samples have been characterized by XRD, SEM, PL, UV-visible spectroscopy and particles size measurement. The results analysis indicates overall improved emission spectrum. It has been observed that the average diameter of RGO (Reduced Graphene Oxide) decreases in presence of ZnO nanoparticles from 3.8?m to 0.41?m.
Air Dispersion Modeling for Building 3026C/D Demolition
Ward, Richard C [ORNL; Sjoreen, Andrea L [ORNL; Eckerman, Keith F [ORNL
2010-06-01T23:59:59.000Z
This report presents estimates of dispersion coefficients and effective dose for potential air dispersion scenarios of uncontrolled releases from Oak Ridge National Laboratory (ORNL) buildings 3026C, 3026D, and 3140 prior to or during the demolition of the 3026 Complex. The Environmental Protection Agency (EPA) AERMOD system1-6 was used to compute these estimates. AERMOD stands for AERMIC Model, where AERMIC is the American Meteorological Society-EPA Regulatory Model Improvement Committee. Five source locations (three in building 3026D and one each in building 3026C and the filter house 3140) and associated source characteristics were determined with the customer. In addition, the area of study was determined and building footprints and intake locations of air-handling systems were obtained. In addition to the air intakes, receptor sites consisting of ground level locations on four polar grids (50 m, 100 m, 200 m, and 500 m) and two intersecting lines of points (50 m separation), corresponding to sidewalks along Central Avenue and Fifth Street. Three years of meteorological data (2006 2008) were used each consisting of three datasets: 1) National Weather Service data; 2) upper air data for the Knoxville-Oak Ridge area; and 3) local weather data from Tower C (10 m, 30 m and 100 m) on the ORNL reservation. Annual average air concentration, highest 1 h average and highest 3 h average air concentrations were computed using AERMOD for the five source locations for the three years of meteorological data. The highest 1 h average air concentrations were converted to dispersion coefficients to characterize the atmospheric dispersion as the customer was interested in the most significant response and the highest 1 h average data reflects the best time-averaged values available from the AERMOD code. Results are presented in tabular and graphical form. The results for dose were obtained using radionuclide activities for each of the buildings provided by the customer.7 Radiation dose was calculated assuming complete release of the building inventory as information was lacking regarding the portion of the building inventory expected to be released. Thus the results are derived using an extremely conservative release as documented in the Preliminary Hazard Screening report.7 To more closely approximate the result of a release, one must estimate the fraction of the total inventory released and multiply the results described above by that fraction. An example of how this calculation is accomplished is provided. Should an actual uncontrolled release occur, the results of this modeling effort could only be used to establish a rough order-of-magnitude for the event.
Low-pressure debris dispersal from scaled reactor cavities
Nichols, R.T.; Tarbell, W.W.
1988-01-01T23:59:59.000Z
During a severe nuclear reactor accident, degradation of the core may result in debris accumulating in the lower head. Upon failure of the head, the melt may be ejected under pressure through the cavity and into the containment building. Under low system pressure conditions, understanding the mechanisms of debris dispersal is instrumental in assessing the response of the containment to pressurized melt ejection. Current analytical approaches rely on empirical correlations for debris entrainment criteria and very simple gas flow patterns in the cavity. The work reported here is directed toward performing scaled experiments that will develop a data base for refined scaling analyses. Subsequently, extrapolations from the analyses to reactor scale may be performed to provide insight for accident predictions. Mechanistic models for gas flow through the cavity and entrainment of the debris are also being developed from the results presented here. The objective of the test matrix is to vary key parameters to assess the effect on the physical processes of dispersal of the melt from the reactor cavity at low system pressures.
Vacuum fluctuations in theories with deformed dispersion relations
Michele Arzano; Giulia Gubitosi; Joao Magueijo; Giovanni Amelino-Camelia
2015-06-15T23:59:59.000Z
We examine vacuum fluctuations in theories with modified dispersion relations which represent dimensional reduction at high energies. By changing units of energy and momentum we can obtain a description rendering the dispersion relations undeformed and transferring all the non-trivial effects to the integration measure in momentum space. Using this description we propose a general quantization procedure, which should be applicable whether or not the theory explicitly introduces a preferred frame. Based on this scheme we evaluate the power spectrum of quantum vacuum fluctuations. We find that in {\\it all} theories which run to 2 dimensions in the ultraviolet the vacuum fluctuations, in the ultraviolet regime, are scale-invariant. This is true in flat space but also for "inside the horizon" modes in an expanding universe. We spell out the conditions upon the gravity theory for this scale-invariance to be preserved as the modes are frozen-in outside the horizon. We also digress on the meaning of dimensionality (in momentum and position space) and suggest that the spectral index could itself provide an operational definition of dimensionality.
Velocity dispersion and upscaling in a laboratory-simulated VSP
Rio, P.; Mukerji, T.; Mavko, G. [Stanford Univ., CA (United States)] [Stanford Univ., CA (United States); Marion, D. [Elf Aquitaine, Pau (France)] [Elf Aquitaine, Pau (France)
1996-03-01T23:59:59.000Z
A laboratory and numerical study was conducted to investigate the impact of scale-dependent seismic wave propagation in randomly layered media, as applied to sonic logs, surface seismic, and vertical seismic profiles (VSPs). Analysis of the laboratory results (1) confirmed the wavelength dependence of velocities inferred from traveltimes, (2) indicated that scale effects can introduce traveltime errors when upscaling from logs to surface seismic and VSPs, and (3) illustrated that erroneous VSP interval velocities can result when layer thicknesses are smaller than about one-tenth of the wavelength. A simple approximate recipe is presented for estimating these traveltimes by successively filtering the medium using a running Backus average and ray theory. The scale-dependent dispersion was also predicted well using a more rigorous invariant imbedding formulation. The predicted traveltimes, using the approximate recipe, compare well with the times observed in the laboratory stack of steel and plastic layers and in numerical studies of stratified media. The dispersion curves predicted by the approximate method also show the overall behavior computed with the more rigorous invariant imbedding formulation.
Critical review of studies on atmospheric dispersion in coastal regions
Shearer, D.L.; Kaleel, R.J.
1982-09-01T23:59:59.000Z
This study effort was required as a preliminary step prior to initiation of field measurements of atmospheric dispersion in coastal regions. The Nuclear Regulatory Commission (NRC) is in the process of planning an extensive field measurement program to generate data which will serve as improved data bases for licensing decisions, confirmation of regulations, standards, and guides, and for site characterizations. The study being reported here is an effort directed to obtaining as much information as is possible from existing studies that is relevant toward NRC's objectives. For this study, reports covering research and meteorological measurements conducted for industrial purposes, utility needs, military objectives, and academic studies were obtained and critically reviewed in light of NRC's current data needs. This report provides an interpretation of the extent of existing usable information, an indication of the potential for tailoring existing research toward current NRC information needs, and recommendations for several follow-on studies which could provide valuable additional information through reanalysis of the data. Recommendations are also offered regarding new measurement programs. Emphasis is placed on the identification and acquisition of data from atmospheric tracer studies conducted in coastal regions. A total of 225 references were identified which deal with the coastal atmosphere, including meteorological and tracer measurement programs, theoretical descriptions of the relevant processes, and dispersion models.
Structure and Osmotic Pressure of Ionic Microgel Dispersions
Mary M. Hedrick; Jun Kyung Chung; Alan R. Denton
2015-01-23T23:59:59.000Z
We investigate structural and thermodynamic properties of aqueous dispersions of ionic microgels -- soft colloidal gel particles that exhibit unusual phase behavior. Starting from a coarse-grained model of microgel macroions as charged spheres that are permeable to microions, we perform simulations and theoretical calculations using two complementary implementations of Poisson-Boltzmann (PB) theory. Within a one-component model, based on a linear-screening approximation for effective electrostatic pair interactions, we perform molecular dynamics simulations to compute macroion-macroion radial distribution functions, static structure factors, and macroion contributions to the osmotic pressure. For the same model, using a variational approximation for the free energy, we compute both macroion and microion contributions to the osmotic pressure. Within a spherical cell model, which neglects macroion correlations, we solve the nonlinear PB equation to compute microion distributions and osmotic pressures. By comparing the one-component and cell model implementations of PB theory, we demonstrate that the linear-screening approximation is valid for moderately charged microgels. By further comparing cell model predictions with simulation data for osmotic pressure, we chart the cell model's limits in predicting osmotic pressures of salty dispersions.
Short-duration radio bursts with apparent extragalactic dispersion
Saint-Hilaire, P. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Benz, A. O.; Monstein, C., E-mail: shilaire@ssl.berkeley.edu [Institute for Astronomy, ETH Zurich, 8093 Zurich (Switzerland)
2014-11-01T23:59:59.000Z
We present the results of the longest yet undertaken search for apparently extragalactic radio bursts at the Bleien Radio Observatory covering 21,000 hr (898 days). The data were searched for events of less than 50 ms FWHM duration showing a ?{sup –2} drift in the spectrogram characteristic of the delay of radio waves in plasma. We have found five cases suggesting dispersion measures between 350 and 400 cm{sup –3} pc while searching in the range of 75-2000 cm{sup –3} pc. Four of the five events occurred between 10:27 and 11:24 a.m. local civil time. The only exception occurred at night with the full Moon in the beam. It was an event that poorly fits plasma dispersion, but had the characteristics of a solar Type III burst. However, we were not able to confirm that it was a lunar reflection. All events were observed with a log-periodic dipole within 6800 hr, but none with a more directional horn antenna observing the rest of the time. These properties suggest a terrestrial origin of the 'peryton' type reported before. However, the cause of these events remains ambiguous.
Boyer, Edmond
to chemically dispersed oil2 3 Luna-Acosta, A.a,* , Kanan, R.b , Le Floch, S.b , Huet, V.a , Pineau P;Abstract: The aim of this study was to evaluate the effects of chemically dispersed oil on an20 of the chemical dispersant. After 2 days of exposure to chemically dispersed28 oil, alkylated naphthalenes
Paris-Sud XI, Université de
) exposed to dispersed crude oil2 3 Thomas Milinkovitch1* , Awa Ndiaye2 , Wilfried Sanchez2 , Stéphane Le ; CD : Chemically Dispersed oil ; D : Dispersant solution ; MD : Mechanically Dispersed oil; WSF application is an oil spill response technique. To evaluate the environmental31 cost of this operation
Efficiency of dispersive wave generation in dual concentric core microstructured fiber
Modotto, Daniele; Krupa, Katarzyna; Manili, Gabriele; Minoni, Umberto; Tonello, Alessandro; Couderc, Vincent; Barthélémy, Alain; Labruyère, Alexis; Shalaby, Badr Mohammed; Leproux, Philippe; Wabnitz, Stefan; Aceves, Alejandro B
2015-01-01T23:59:59.000Z
We describe the generation of powerful dispersive waves that are observed when pumping a dual concentric core microstructured fiber by means of a sub-nanosecond laser emitting at the wavelength of~1064 nm. The presence of three zeros in the dispersion curve, their spectral separation from the pump wavelength, and the complex dynamics of solitons originated by the pump pulse break-up, all contribute to boost the amplitude of the dispersive wave on the long-wavelength side of the pump. The measured conversion efficiency towards the dispersive wave at 1548 nm is as high as 50%. Our experimental analysis of the output spectra is completed by the acquisition of the time delays of the different spectral components. Numerical simulations and an analytical perturbative analysis identify the central wavelength of the red-shifted pump solitons and the dispersion profile of the fiber as the key parameters for determining the efficiency of the dispersive wave generation process.
The relation between seismic P- and S-wave velocity dispersion in saturated rocks
Mavko, G. [Stanford Univ., CA (United States). Dept. of Geophysics] [Stanford Univ., CA (United States). Dept. of Geophysics; Jizba, D. [CSTJF, Pau (France)] [CSTJF, Pau (France)
1994-01-01T23:59:59.000Z
Seismic velocity dispersion in fluid-saturated rocks appears to be dominated by two mechanisms: the large scale mechanism modeled by Biot, and the local flow or squirt mechanism. The two mechanisms can be distinguished by the ratio of P- to S-wave dispersions, or more conveniently, by the ratio of dynamic bulk to shear compliance dispersions derived from the wave velocities. The authors` formulation suggests that when local flow dominates, the dispersion of the shear compliance will be approximately 4/15 the dispersion of the compressibility. When the Biot mechanism dominates, the constant of proportionality is much smaller. Their examination of ultrasonic velocities from 40 sandstones and granites shows that most, but not all, of the samples were dominated by local flow dispersion, particularly at effective pressures below 40 MPa.
AHF: Array-Based Half-Facet Data Structure for Mixed-Dimensional and Non-Manifold Meshes
Dyedov, Volodymyr; Ray, Navamita; Einstein, Daniel R.; Jiao, Xiangmin; Tautges, T.
2014-08-31T23:59:59.000Z
We present an Array-based Half-Facet mesh data structure, or AHF, for efficient mesh query and modification operations. The AHF extends the compact array-based half-edge and half-face data structures (T.J. Alumbaugh and X. Jiao, Compact array-based mesh data structures, IMR, 2005) to support mixed-dimensional and non-manifold meshes. The design goals of our data structure include generality to support such meshes, efficiency of neighborhood queries and mesh modification, compactness of memory footprint, and facilitation of interoperability of mesh-based application codes. To accomplish these goals, our data structure uses sibling half-facets as a core abstraction, coupled with other explicit and implicit representations of entities. A unique feature of our data structure is a comprehensive implementation in MATLAB, which allows rapid prototyping, debugging, testing, and deployment of meshing algorithms and other mesh-based numerical methods. We have also developed C++ implementation built on top of MOAB (T.J. Tautges, R. Meyers, and K. Merkley, MOAB: A Mesh-Oriented Database, Sandia National Laboratories, 2004). We present some comparisons of the memory requirements and computational costs, and also demonstrate its effectiveness with a few sample applications.
Not Available
1991-09-01T23:59:59.000Z
The design of a CGMCFC electric generation plant that will provide a cost of eletricity (COE) which is lower than that of current electric generation technologies and which is competitive with other long-range electric generating systems is presented. This effort is based upon the Internal Manifold Heat Exchanger (IMHEX) technology as developed by the Institute of Gas Technology (IGT). The project was executed by selecting economic and performance objectives for alternative plant arrangements while considering process constraints identified during IMHEX fuel cell development activities at ICT. The four major subsystems of a coal-based MCFC power plant are coal gasification, gas purification, fuel cell power generation and the bottoming cycle. The design and method of operation of each subsystem can be varied, and, depending upon design choices, can have major impact on both the design of other subsystems and the resulting cost of electricity. The challenge of this project was to select, from a range of design parameters, those operating conditions that result in a preferred plant design. Computer modelling was thus used to perform sensitivity analyses of as many system variables as program resources and schedules would permit. In any systems analysis, it is imperative that the evaluation methodology be verifiable and comparable. The TAG Class I develops comparable (if imprecise) data on performance and costs for the alternative cases being studied. It identifies, from a range of options, those which merit more exacting scrutiny to be undertaken at the second level, TAG class II analysis.
Dispersion-managed dark solitons in erbium-doped fiber lasers
Zhang, Han; Tlidi, Mustapha; Zhao, Luming; Wu, Xuan
2010-01-01T23:59:59.000Z
We report on the observation of dispersion-managed (DM) dark soliton emission in a net-normal dispersion erbium-doped fiber laser. We found experimentally that dispersion management could not only reduce the pump threshold for the dark soliton formation in a fiber laser, but also stabilize the single dark soliton evolution in the cavity. Numerical simulations have also confirmed the DM dark soliton formation in a fiber laser.
Dispersion-managed dark solitons in erbium-doped fiber lasers
Han Zhang; Dingyuan Tang; Mustapha Tlidi; Luming Zhao; Xuan Wu
2010-07-19T23:59:59.000Z
We report on the observation of dispersion-managed (DM) dark soliton emission in a net-normal dispersion erbium-doped fiber laser. We found experimentally that dispersion management could not only reduce the pump threshold for the dark soliton formation in a fiber laser, but also stabilize the single dark soliton evolution in the cavity. Numerical simulations have also confirmed the DM dark soliton formation in a fiber laser.
Submesoscale dispersion in the vicinity of the Deepwater Horizon spill
Poje, Andrew C; Lipphardt,, Bruce; Haus, Brian K; Ryan, Edward H; Haza, Angelique C; Reniers, A J H M; Olascoaga, Josefina; Novelli, Guillaume; Beron-Vera, Francisco J; Chen, Shuyi; Mariano, Arthur J; Jacobs, Gregg; Hogan, Pat; Coelho, Emanuel; Kirwan,, A D; Huntley, Helga; Griffa, Annalisa
2014-01-01T23:59:59.000Z
Reliable forecasts for the dispersion of oceanic contamination are important for coastal ecosystems, society and the economy as evidenced by the Deepwater Horizon oil spill in the Gulf of Mexico in 2010 and the Fukushima nuclear plant incident in the Pacific Ocean in 2011. Accurate prediction of pollutant pathways and concentrations at the ocean surface requires understanding ocean dynamics over a broad range of spatial scales. Fundamental questions concerning the structure of the velocity field at the submesoscales (100 meters to tens of kilometers, hours to days) remain unresolved due to a lack of synoptic measurements at these scales. \\textcolor{black} {Using high-frequency position data provided by the near-simultaneous release of hundreds of accurately tracked surface drifters, we study the structure of submesoscale surface velocity fluctuations in the Northern Gulf Mexico. Observed two-point statistics confirm the validity of classic turbulence scaling laws at 200m$-$50km scales and clearly indicate tha...
Methods and apparatus for controlling dispersions of nanoparticles
Lavrentovich, Oleg D; Golovin, Andrii B
2014-10-21T23:59:59.000Z
Electrically reconfigurable metamaterial with spatially varied refractive index is proposed for applications such as optical devices and lenses. The apparatus and method comprises a metamaterial in which the refractive indices are modified in space and time by applying one or more electric fields. The metamaterials are electrically controllable and reconfigurable, and consist of metal (gold, silver, etc.) particles of different shapes, such as rods, with dimension much smaller than the wavelength of light, dispersed in a dielectric medium. The metamaterial is controlled by applying a non-uniform electric field that causes two effects: (1) It aligns the metallic anisometric particles with respect to the direction of the applied electric field and (2) It redistributes particles in space, making their local concentration position dependent.
Time delay for dispersive systems in quantum scattering theory
Rafael Tiedra de Aldecoa
2008-10-06T23:59:59.000Z
We consider time delay and symmetrised time delay (defined in terms of sojourn times) for quantum scattering pairs $\\{H_0=h(P),H\\}$, where $h(P)$ a dispersive operator of hypoelliptic-type. For instance $h(P)$ can be one of the usual elliptic operators such as the Schr\\"odinger operator $h(P)=P^2$ or the square-root Klein-Gordon operator $h(P)=\\sqrt{1+P^2}$. We show under general conditions that the symmetrised time delay exists for all smooth even localization functions. It is equal to the Eisenbud-Wigner time delay plus a contribution due to the non-radial component of the localization function. If the scattering operator $S$ commutes with some function of the velocity operator $\
Urban Dispersion Program Overview and MID05 Field Study Summary
Allwine, K Jerry; Flaherty, Julia E.
2007-07-31T23:59:59.000Z
The Urban Dispersion Program (UDP) was a 4-year project (2004–2007) funded by the U.S. Department of Homeland Security with additional support from the Defense Threat Reduction Agency. The U.S. Environmental Protection Agency (EPA) also contributed to UDP through funding a human-exposure component of the New York City (NYC) field studies in addition to supporting an EPA scientist in conducting modeling studies of NYC. The primary goal of UDP was to improve the scientific understanding of the flow and diffusion of airborne contaminants through and around the deep street canyons of NYC. The overall UDP project manager and lead scientist was Dr. Jerry Allwine of Pacific Northwest National Laboratory. UDP had several accomplishments that included conducting two tracer and meteorological field studies in Midtown Manhattan.
Modulus dispersion and attenuation in tuff and granite
Haupt, R.W.; Martin, R.J. III; Tang, X.; Dupree, W.J. [New England Research, Inc., White River Junction, VT (United States); Price, R.H. [Sandia National Labs., Albuquerque, NM (United States)
1991-12-23T23:59:59.000Z
The effects of loading frequency, strain amplitude, and saturation on elastic moduli and attenuation have been measured in samples of the Topopah Spring Member welded tuff. Four different laboratory techniques have been used to determine Young`s modulus and extensional wave attenuation at frequencies ranging from 10{sup {minus}2} to 10{sup 6} Hz. The results are compared with data acquired for Sierra White granite under the same conditions. The modulus and attenuation in room dry samples remain relatively constant over frequency. Frequency dependent attenuation and modulus dispersion are observed in the saturated samples and are attributed to fluid flow and sample size. The properties of tuff were independent of strain amplitude in room dry and saturated conditions.
Chromatic and Dispersive Effects in Nonlinear Integrable Optics
Webb, Stephen D; Valishev, Alexander; Nagaitsev, Sergei N; Danilov, Viatcheslav V
2015-01-01T23:59:59.000Z
Proton accumulator rings and other circular hadron accelerators are susceptible to intensity-driven parametric instabilities because the zero-current charged particle dynamics are characterized by a single tune. Landau damping can suppress these instabilities, which requires energy spread in the beam or introducing nonlinear magnets such as octupoles. However, this approach reduces dynamic aperture. Nonlinear integrable optics can suppress parametric instabilities independent of energy spread in the distribution, while preserving the dynamic aperture. This novel approach promises to reduce particle losses and enable order-of-magnitude increases in beam intensity. In this paper we present results, obtained using the Lie operator formalism, on how chromaticity and dispersion affect particle orbits in integrable optics. We conclude that chromaticity in general breaks the integrability, unless the vertical and horizontal chromaticities are equal. Because of this, the chromaticity correcting magnets can be weaker ...
Method for dispersing catalyst onto particulate material and product thereof
Utz, Bruce R. (Pittsburgh, PA); Cugini, Anthony V. (Pittsburgh, PA)
1992-01-01T23:59:59.000Z
A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal.
The Photon Dispersion as an Indicator for New Physics ?
Wolfgang Bietenholz
2010-09-02T23:59:59.000Z
We first comment on the search for a deviation from the linear photon dispersion relation, in particular based on cosmic photons from Gamma Ray Bursts. Then we consider the non-commutative space as a theoretical concept that could lead to such a deviation, which would be a manifestation of Lorentz Invariance Violation. In particular we review a numerical study of pure U(1) gauge theory in a 4d non-commutative space. Starting from a finite lattice, we explore the phase diagram and the extrapolation to the continuum and infinite volume. These simultaneous limits - taken at fixed non-commutativity - lead to a phase of broken Poincare symmetry, where the photon appears to be IR stable, despite a negative IR divergence to one loop.
Dispersive Qubit Measurement by Interferometry with Parametric Amplifiers
Sh. Barzanjeh; D. P. DiVincenzo; B. M. Terhal
2014-10-02T23:59:59.000Z
We perform a detailed analysis of how an amplified interferometer can be used to enhance the quality of a dispersive qubit measurement, such as one performed on a superconducting transmon qubit, using homodyne detection on an amplified microwave signal. Our modeling makes a realistic assessment of what is possible in current circuit-QED experiments; in particular, we take into account the frequency-dependence of the qubit-induced phase shift for short microwaves pulses. We compare the possible signal-to-noise ratios obtainable with (single-mode) SU(1,1) interferometers with the current coherent measurement and find a considerable reduction in measurement error probability in an experimentally-accessible range of parameters.
Excitation Theory for Space-Dispersive Active Media Waveguides
Barybin, A A
1999-01-01T23:59:59.000Z
A unified electrodynamic approach to the guided-wave excitation theory is generalized to the waveguiding structures containing a hypothetical space-dispersive medium with drifting charge carriers possessing simultaneously elastic, piezoelectric and magnetic properties. Substantial features of our electrodynamic approach are: (i) the allowance for medium losses and (ii) the separation of potential fields peculiar to the slow quasi-static waves. It is shown that the orthogonal complementary fields appearing inside the external source region are just associated with a contribution of the potential fields inherent in exciting sources. Taking account of medium losses converts the usual orthogonality relation into a novel form called the quasi-orthogonality relation. It is found that the separation of potential fields reveals the fine structure of interaction between the exciting sources and mode eigenfields: in addition to the exciting currents interacting with the curl fields, the exciting charges and the double ...
Dispersive calculation of complex Regge trajectories for the lightest f2 resonances and the K*(892)
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Carrasco, J. A.; Nebreda, J.; Pelaez, Jose R.; Szczepaniak, Adam P.
A recently developed dispersive formalism is applied to calculate the Regge trajectories of the f2(1270), f2(1525) and K*(892) mesons.
A model for P-wave attenuation and dispersion in a porous medium ...
lll
2005-09-05T23:59:59.000Z
Theoretical models of attenuation and dispersion due to wave-induced fluid flow ...... anisotropic layered fluid- and gas-saturated sediments, Geophysics, 62,.
Distribution and Dispersal of the South Pacifc Tree, Fagraea Berteriana (Loganiaceae)
Hanna, Zachary R.
2006-01-01T23:59:59.000Z
addressing the ridge top distribution phenomenon. ADISTRIBUTION AND DISPERSAL OF THE SOUTH PACIFC TREE, FAGRAEAits inter? island distribution in the South Pacific. I
Rothstein, Jonathan
polyethylene oxide solution Sunilkumar Khandavalli and Jonathan P. Rothsteina) Mechanical and Industrial rheology of fumed silica nanoparticles dispersed in an aqueous polyethylene oxide (PEO) solution
Avalanche-like fluidization of an attractive dispersion
Aika Kurokawa; Valérie Vidal; Kei Kurita; Thibaut Divoux; Sébastien Manneville
2015-05-22T23:59:59.000Z
We report on the transient dynamics of an attractive silica dispersion that displays strong physical aging. Extensive rheology coupled to ultrasonic velocimetry allows us to characterize the global stress response together with the local dynamics of the gel during shear startup experiments. In practice, after being rejuvenated by a preshear, the dispersion is left to age during a time $t_w$ before being submitted to a constant shear rate $\\dot \\gamma$. We investigate in detail the effects of both $t_w$ and $\\dot \\gamma$ on the fluidization dynamics and build a complete phase diagram of the gel behavior. At large enough shear rates, the gel is fully fluidized and flows homogeneously independently of its age. Under lower shear rates, the strong interplay between aging and shear rejuvenation leads, together with wall slip, to a more complex phenomenology. The gel may either display transient shear banding towards complete fluidization, or steady-state shear banding. In the former case, we unravel that the progressive fluidization occurs by successive steps that appear as peaks on the global stress relaxation signal. Flow imaging reveals that the shear band grows up to complete fluidization of the material by sudden avalanche-like events that are correlated to large peaks in the slip velocity at the moving wall. In the case of steady-state shear banding, we recover the classical scenario involving a critical shear rate $ \\dot \\gamma_c$ below which no homogeneous steady flow is possible. We show here that $\\dot \\gamma_c$ displays a nonlinear behavior with $t_w$. Our work paves the way for a thorough description of transient flows of weak attractive gels, and highlights the subtle interplay between shear, wall slip and aging that constitutes a major challenge in terms of modeling that has yet not been met.
INVESTIGATION OF THE THERMOCHROMIC PROPERTIES OF POLYTHIOPHENES DISPERSED IN HOST POLYMERS
Euler, William B.
INVESTIGATION OF THE THERMOCHROMIC PROPERTIES OF POLYTHIOPHENES DISPERSED IN HOST POLYMERS Brett L films or in solution. However, the utilization of conjugated polymers in many electronic applications requires them to be dispersed in a host polymer matrix.2 There have been few investigations
Population Ecology at the Range Edge Survival and Dispersal of a High-Density Lepidopteran
Population Ecology at the Range Edge Survival and Dispersal of a High-Density Lepidopteran Population Cecilia Ronnås Faculty of Natural Resources and Agricultural Sciences Department of Ecology Service/Repro, Uppsala 2011 #12;Population Ecology at the Range Edge. Survival and Dispersal of a High
Minimization of the pulse's timing jitter in a dispersion-compensated WDM system
Band, Yehuda B.
Minimization of the pulse's timing jitter in a dispersion-compensated WDM system O F I R A H A R O jitter 1. Introduction It is well known that periodic dispersion compensation is a necessary ingredient of the pulses. This is the source of additional timing jitter that impedes achievement of higher bit rates
Gladden, Josh
Determination of power-law attenuation coefficient and dispersion spectra in multi-wall carbon for a set of multi-wall carbon nanotube MWCNT -nylon composites from pure nylon to 20% MWCNT by weightKronig relations, the attenuation and dispersion data were found to be consistent with a power-law attenuation
Dispersion and Characterization of Nickel Nanostrands in Thermoset and Thermoplastic Polymers
Whalen, Casey Allen
2012-02-14T23:59:59.000Z
research done on dispersing powdered NiNS in various polymer matrices. This thesis covers the research in dispersing NiNS in three separate polymer systems, and related composite processing and characterization. An aromatic polyimide (CP2) is first used...
Coupling traffic models on networks and urban dispersion models for simulating sustainable
Ceragioli, Francesca
models for modeling and testing different traffic scenarios, in order to define the impact on air quality it with the urban dispersion model Sirane. Keywords: urban air quality, macroscopic traffic models, road networks, pollutant dispersion models, traffic emissions control. AMS subject classification: 35L65, 35L67, 60K30, 90B
Modeling of the multiscale dispersion of nanoparticles in a hematite coating , F. Willot1
Boyer, Edmond
Modeling of the multiscale dispersion of nanoparticles in a hematite coating E. Couka1 , F. Willot1 conclude in Sec. (6). 2. Hematite nanocubes coating 2.1. Dispersion of nanoparticles In this work, we-Auguste Desbruères, 91003 Evry, France. Images of a hematite-based epoxy coating are obtained by scanning electron
Washburn, Libe
2004-01-01T23:59:59.000Z
Continental Shelf Research 24 (2004) 20292043 A conceptual model for river water and sediment and Beardsley, 1995; Geyer et al., 1996), while its sediment is dispersed primarily by bottom bound- ary layer dispersal in the Santa Barbara Channel, California Jonathan A. Warricka,Ã, Leal A.K. Mertesb , Libe
Fractional advection-dispersion equations for1 modeling transport at the Earth surface2
Bäumer, Boris
Fractional advection-dispersion equations for1 modeling transport at the Earth surface2 Rina partial differential equations such as the advection-dispersion equation12 (ADE) begin with assumptions biomechanical transport and mixing29 by bioturbation, and the transport of sediment particles and sediment
Different generation regimes of mode-locked all-positive-dispersion all-fiber Yb laser
Kobtsev, Sergei M.
to achieve stable mode-locking and ultra-short pulse generation in an all-positive dispersion cavityDifferent generation regimes of mode-locked all-positive-dispersion all-fiber Yb laser Sergey Kobtseva , Sergey Kukarina , Sergey Smirnova , Sergey Turitsynb , Anton Latkina a Laser system laboratory
Wang, Yuqing
"ventilation" flow over the TC core), Rossby waves emit energy east- ward and equatorward. As a resultTropical Cyclone Energy Dispersion in a Three-Dimensional Primitive Equation Model: Upper The three-dimensional (3D) Rossby wave energy dispersion of a tropical cyclone (TC) is studied using
Price Dispersion in the Housing Market: The Role of Bargaining and Search Costs
Boyer, Edmond
Price Dispersion in the Housing Market: The Role of Bargaining and Search Costs Gaetano Lisi bargaining powers and search costs the selling price will be different. Recently, from a theoretical point a basic fact of housing markets: price dispersion. The variance in house prices is basically due to both
Investigation of mode coupling in normal-dispersion silicon nitride microresonators
Purdue University
-dispersion devices highlight mode interactions as a beneficial tool for comb initiation and pulse formation. © 2014Investigation of mode coupling in normal- dispersion silicon nitride microresonators for Kerr microresonators are the subject of intense study for potential applications ranging from short pulse generation
Gain dispersion in Visible Light Photon Counters as a function of counting rate
Bross, A.; /Fermilab; Buscher, V.; /Freiburg U.; Estrada, J.; /Fermilab; Ginther, G.; /Rochester U.; Molina, J.; /Rio de Janeiro State U.
2005-03-01T23:59:59.000Z
We present measurements of light signals using Visible Light Photon Counters (VLPC), that indicate an increase in gain dispersion as the counting rate increases. We show that this dispersion can be understood on the basis of a recent observation of localized field reduction in VLPCs at high input rates.
Cyclogenesis Simulation of Typhoon Prapiroon (2000) Associated with Rossby Wave Energy Dispersion*
Li, Tim
2000-01-01T23:59:59.000Z
Cyclogenesis Simulation of Typhoon Prapiroon (2000) Associated with Rossby Wave Energy Dispersion (2000), in the western North Pacific, is simulated to understand the role of Rossby wave energy process is through the conventional barotropic Rossby wave energy dispersion, which enhances the low
Analysis of Thermal Dispersion in an Array of Parallel Plates with Fully-Developed Laminar Flow
Fleck, Norman A.
basic heat transfer problems are addressed, each for steady fully-developed laminar fluid flow: (a1 Analysis of Thermal Dispersion in an Array of Parallel Plates with Fully-Developed Laminar Flow dispersion, parallel plate array, fully-developed laminar flow, Peclet number #12;2 Notation a molecular
Dispersion and Characterization of Nickel Nanostrands in Thermoset and Thermoplastic Polymers
Whalen, Casey Allen
2012-02-14T23:59:59.000Z
research done on dispersing powdered NiNS in various polymer matrices. This thesis covers the research in dispersing NiNS in three separate polymer systems, and related composite processing and characterization. An aromatic polyimide (CP2) is first used...
Dispersion of swimming algae in laminar and turbulent channel flows: theory and simulations
Croze, O A; Ahmed, M; Bees, M A; Brandt, L
2012-01-01T23:59:59.000Z
Algal swimming is often biased by environmental cues, e.g. gravitational and viscous torques drive cells towards downwelling fluid (gyrotaxis). In view of biotechnological applications, it is important to understand how such biased swimming affects cell dispersion in a flow. Here, we study the dispersion of gyrotactic swimming algae in laminar and turbulent channel flows. By direct numerical simulation (DNS) of cell motion within upwelling and downwelling channel flows, we evaluate time-dependent measures of dispersion for increasing values of the flow Peclet (Reynolds) numbers, Pe (Re). Furthermore, we derive an analytical `swimming Taylor-Aris dispersion' theory, using flow-dependent transport parameters given by existing microscopic models. In the laminar regime, DNS results and analytical predictions compare very well, providing the first confirmation that cells' response to flow is best described by the generalized-Taylor-dispersion microscopic model. We predict that cells drift along a channel faster th...
Acoustic dispersion in a two-dimensional dipole system
Golden, Kenneth I.; Kalman, Gabor J.; Donko, Zoltan; Hartmann, Peter [Department of Mathematics and Statistics, College of Engineering and Mathematical Sciences, University of Vermont, Burlington, Vermont 05401-1455 (United States); Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467 (United States); Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary)
2008-07-15T23:59:59.000Z
We calculate the full density response function and from it the long-wavelength acoustic dispersion for a two-dimensional system of strongly coupled point dipoles interacting through a 1/r{sup 3} potential at arbitrary degeneracy. Such a system has no random-phase-approximation (RPA) limit and the calculation has to include correlations from the outset. We follow the quasilocalized charge (QLC) approach, accompanied by molecular-dynamics (MD) simulations. Similarly to what has been recently reported for the closely spaced classical electron-hole bilayer [G. J. Kalman et al., Phys. Rev. Lett. 98, 236801 (2007)] and in marked contrast to the RPA, we report a long-wavelength acoustic phase velocity that is wholly maintained by particle correlations and varies linearly with the dipole moment p. The oscillation frequency, calculated both in an extended QLC approximation and in the Singwi-Tosi-Land-Sjolander approximation [Phys. Rev. 176, 589 (1968)], is invariant in form over the entire classical to quantum domains all the way down to zero temperature. Based on our classical MD-generated pair distribution function data and on ground-state energy data generated by recent quantum Monte Carlo simulations on a bosonic dipole system [G. E. Astrakharchik et al., Phys. Rev. Lett. 98, 060405 (2007)], there is a good agreement between the QLC approximation kinetic sound speeds and the standard thermodynamic sound speeds in both the classical and quantum domains.
Dispersal of Gaseous Circumstellar Discs around High-Mass Stars
Yue Shen; Yu-Qing Lou
2006-05-19T23:59:59.000Z
We study the dispersal of a gaseous disc surrounding a central high-mass stellar core once this circumstellar disc becomes fully ionized. If the stellar and surrounding EUV and X-ray radiations are so strong as to rapidly heat up and ionize the entire circumstellar disc as further facilitated by disc magnetohydrodynamic (MHD) turbulence, a shock can be driven to travel outward in the fully ionized disc, behind which the disc expands and thins. For an extremely massive and powerful stellar core, the ionized gas pressure overwhelms the centrifugal and gravitational forces in the disc. In this limit, we construct self-similar shock solutions for such an expansion and depletion phase. As a significant amount of circumstellar gas being removed, the relic disc becomes vulnerable to strong stellar winds and fragments into clumps. We speculate that disc disappearance happens rapidly, perhaps on a timescale of $\\sim 10^3-10^4\\hbox{yr}$ once the disc becomes entirely ionized sometime after the onset of thermal nuclear burning in a high-mass stellar core.
The Impact of Dust Evolution and Photoevaporation on Disk Dispersal
Gorti, Uma; Dullemond, Cornelis
2015-01-01T23:59:59.000Z
Protoplanetary disks are dispersed by viscous evolution and photoevaporation in a few million years; in the interim small, sub-micron sized dust grains must grow and form planets. The time-varying abundance of small grains in an evolving disk directly affects gas heating by far-ultraviolet photons, while dust evolution affects photoevaporation by changing the disk opacity and resulting penetration of FUV photons in the disk. Photoevaporative flows, in turn, selectively carry small dust grains leaving the larger particles---which decouple from the gas---behind in the disk. We study these effects by investigating the evolution of a disk subject to viscosity, photoevaporation by EUV, FUV and X-rays, dust evolution, and radial drift using a 1-D multi-fluid approach (gas + different dust grain sizes) to solve for the evolving surface density distributions. The 1-D evolution is augmented by 1+1D models constructed at each epoch to obtain the instantaneous disk structure and determine photoevaporation rates. The imp...
Viscosity of alumina nanoparticles dispersed in car engine coolant
Kole, Madhusree; Dey, T.K. [Thermophysical Measurements Laboratory, Cryogenic Engineering Centre, Indian Institute of Technology, Kharagpur 721 302 (India)
2010-09-15T23:59:59.000Z
The present paper, describes our experimental results on the viscosity of the nanofluid prepared by dispersing alumina nanoparticles (<50 nm) in commercial car coolant. The nanofluid prepared with calculated amount of oleic acid (surfactant) was tested to be stable for more than 80 days. The viscosity of the nanofluids is measured both as a function of alumina volume fraction and temperature between 10 and 50 C. While the pure base fluid display Newtonian behavior over the measured temperature, it transforms to a non-Newtonian fluid with addition of a small amount of alumina nanoparticles. Our results show that viscosity of the nanofluid increases with increasing nanoparticle concentration and decreases with increase in temperature. Most of the frequently used classical models severely under predict the measured viscosity. Volume fraction dependence of the nanofluid viscosity, however, is predicted fairly well on the basis of a recently reported theoretical model for nanofluids that takes into account the effect of Brownian motion of nanoparticles in the nanofluid. The temperature dependence of the viscosity of engine coolant based alumina nanofluids obeys the empirical correlation of the type: log ({mu}{sub nf}) = A exp(BT), proposed earlier by Namburu et al. (author)
Particle dispersing system and method for testing semiconductor manufacturing equipment
Chandrachood, Madhavi (Sunnyvale, CA); Ghanayem, Steve G. (Sunnyvale, CA); Cantwell, Nancy (Milpitas, CA); Rader, Daniel J. (Albuquerque, NM); Geller, Anthony S. (Albuquerque, NM)
1998-01-01T23:59:59.000Z
The system and method prepare a gas stream comprising particles at a known concentration using a particle disperser for moving particles from a reservoir of particles into a stream of flowing carrier gas. The electrostatic charges on the particles entrained in the carrier gas are then neutralized or otherwise altered, and the resulting particle-laden gas stream is then diluted to provide an acceptable particle concentration. The diluted gas stream is then split into a calibration stream and the desired output stream. The particles in the calibration stream are detected to provide an indication of the actual size distribution and concentration of particles in the output stream that is supplied to a process chamber being analyzed. Particles flowing out of the process chamber within a vacuum pumping system are detected, and the output particle size distribution and concentration are compared with the particle size distribution and concentration of the calibration stream in order to determine the particle transport characteristics of a process chamber, or to determine the number of particles lodged in the process chamber as a function of manufacturing process parameters such as pressure, flowrate, temperature, process chamber geometry, particle size, particle charge, and gas composition.
Cryogenic properties of dispersion strengthened copper for high magnetic fields
Toplosky, V. J.; Han, K.; Walsh, R. P. [National High Magnetic Field Laboratory, Tallahassee, FL 32310 (United States); Swenson, C. A. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)
2014-01-27T23:59:59.000Z
Cold deformed copper matrix composite conductors, developed for use in the 100 tesla multi-shot pulsed magnet at the National High Magnetic Field Laboratory (NHMFL), have been characterized. The conductors are alumina strengthened copper which is fabricated by cold drawing that introduces high dislocation densities and high internal stresses. Both alumina particles and high density of dislocations provide us with high tensile strength and fatigue endurance. The conductors also have high electrical conductivities because alumina has limited solubility in Cu and dislocations have little scattering effect on conduction electrons. Such a combination of high strength and high conductivity makes it an excellent candidate over other resistive magnet materials. Thus, characterization is carried out by tensile testing and fully reversible fatigue testing. In tensile tests, the material exceeds the design criteria parameters. In the fatigue tests, both the load and displacement were measured and used to control the amplitude of the tests to simulate the various loading conditions in the pulsed magnet which is operated at 77 K in a non-destructive mode. In order to properly simulate the pulsed magnet operation, strain-controlled tests were more suitable than load controlled tests. For the dispersion strengthened coppers, the strengthening mechanism of the aluminum oxide provided better tensile and fatigue properties over convention copper.
Oxide Dispersion Strengthened Iron Aluminide by CVD Coated Powders
Asit Biswas Andrew J. Sherman
2006-09-25T23:59:59.000Z
This I &I Category2 program developed chemical vapor deposition (CVD) of iron, aluminum and aluminum oxide coated iron powders and the availability of high temperature oxidation, corrosion and erosion resistant coating for future power generation equipment and can be used for retrofitting existing fossil-fired power plant equipment. This coating will provide enhanced life and performance of Coal-Fired Boilers components such as fire side corrosion on the outer diameter (OD) of the water wall and superheater tubing as well as on the inner diameter (ID) and OD of larger diameter headers. The program also developed a manufacturing route for readily available thermal spray powders for iron aluminide coating and fabrication of net shape component by powder metallurgy route using this CVD coated powders. This coating can also be applid on jet engine compressor blade and housing, industrial heat treating furnace fixtures, magnetic electronic parts, heating element, piping and tubing for fossil energy application and automotive application, chemical processing equipment , heat exchanger, and structural member of aircraft. The program also resulted in developing a new fabrication route of thermal spray coating and oxide dispersion strengthened (ODS) iron aluminide composites enabling more precise control over material microstructures.
Dispersion of radioactive pollutant in a tornadic storm
Pepper, D.W.
1981-05-01T23:59:59.000Z
A three-dimensional numerical model is used to calculate ground-level air concentration and deposition (due to precipitation scavenging) after a hypothetical tornado strike at a plutonium fabrication facility in Pennsylvania. Plutonium particles less than 10 ..mu..m in diameter are assumed to be lifted into the tornadic storm cell by the vortex. The rotational characteristics of the tornadic storm are embedded within the larger mesoscale flow of the storm system. The design-basis translational wind values are based on probabilities associated with existing records of tornado strikes in the vicinity of the plant site. Turbulence exchange coefficients are based on empirical values deduced from experimental data in severe storms and from theoretical assumptions obtained from the literature. The quasi-Lagrangian method of moments is used to model the transport of concentration within a grid cell volume. In all case studies, the effects of updrafts and downdrafts, coupled with scavenging of the particulates by precipitation, account for most of the material being deposited within 20 to 45 km downwind of the plant site. Ground-level isopleths in the x-y plane show that most of the material is deposited behind and slightly to the left of the centerline trajectory of the storm. Approximately 5% of the material is dispersed into the stratosphere and anvil section of the storm.
Do dispersive waves play a role in collisionless magnetic reconnection?
Liu, Yi-Hsin; Daughton, W.; Li, H. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Karimabadi, H. [SciberQuest, Del Mar, California 92014 (United States) [SciberQuest, Del Mar, California 92014 (United States); Department of Electrical and Computer Engineering, UCSD, La Jolla, California 92093 (United States); Peter Gary, S. [Space Science Institute, Boulder, Colorado 80301 (United States)] [Space Science Institute, Boulder, Colorado 80301 (United States)
2014-02-15T23:59:59.000Z
Using fully kinetic simulations, we demonstrate that the properly normalized reconnection rate is fast ?0.1 for guide fields up to 80× larger than the reconnecting field and is insensitive to both the system size and the ion to electron mass ratio. These results challenge conventional explanations of reconnection based on fast dispersive waves, which are completely absent for sufficiently strong guide fields. In this regime, the thickness of the diffusion layer is set predominantly by the electron inertial length with an inner sublayer that is controlled by finite gyro-radius effects. As the Alfvén velocity becomes relativistic for very strong guide fields, the displacement current becomes important and strong deviations from charge neutrality occur, resulting in the build-up of intense electric fields which absorb a portion of the magnetic energy release. Over longer time scales, secondary magnetic islands are generated near the active x-line while an electron inertial scale Kelvin-Helmholtz instability is driven within the outflow. These secondary instabilities give rise to time variations in the reconnection rate but do not alter the average value.
Przepiora, Andrzej
1995-01-01T23:59:59.000Z
geochemical and mineralogical factors controlling particle dispersion and pollutant sorption must be identified. These factors were determined through characterization of water-dispersible clay (WDC) assumed to be an analog of natural mobile particles. WDC...
Dispersion relation for pure dust Bernstein waves in a non-Maxwellian magnetized dusty plasma
Deeba, F. [National Tokamak Fusion Program, PAEC, P.O. Box 3329, Islamabad 44000 (Pakistan); Department of Physics, G.C. University, Lahore 54000 (Pakistan); Ahmad, Zahoor [National Tokamak Fusion Program, PAEC, P.O. Box 3329, Islamabad 44000 (Pakistan); Murtaza, G. [Salam Chair in Physics, G.C. University, Lahore 54000 (Pakistan)
2011-07-15T23:59:59.000Z
Pure dust Bernstein waves are investigated using non-Maxwellian kappa and (r,q) distribution functions in a collisionless, uniform magnetized dusty plasma. Dispersion relations for both the distributions are derived by considering waves whose frequency is of the order of dust cyclotron frequency, and dispersion curves are plotted. It is observed that the propagation band for dust Bernstein waves is rather narrow as compared with that of the electron Bernstein waves. However, the band width increases for higher harmonics, for both kappa and (r,q) distributions. Effect of dust charge on dispersion curves is also studied, and one observes that with increasing dust charge, the dispersion curves shift toward the lower frequencies. Increasing the dust to ion density ratio ((n{sub d0}/n{sub i0})) causes the dispersion curve to shift toward the higher frequencies. It is also found that for large values of spectral index kappa ({kappa}), the dispersion curves approach to the Maxwellian curves. The (r,q) distribution approaches the kappa distribution for r = 0, whereas for r > 0, the dispersion curves show deviation from the Maxwellian curves as expected. Relevance of this work can be found in astrophysical plasmas, where non-Maxwellian velocity distributions as well as dust particles are commonly observed.
Federal Response Assets for a Radioactive Dispersal Device Incident
Sullivan,T.
2009-06-30T23:59:59.000Z
If a large scale RDD event where to occur in New York City, the magnitude of the problem would likely exceed the capabilities of City and State to effectively respond to the event. New York State could request Federal Assistance if the United States President has not already made the decision to provide it. The United States Federal Government has a well developed protocol to respond to emergencies. The National Response Framework (NRF) describes the process for responding to all types of emergencies including RDD incidents. Depending on the location and type of event, the NRF involves appropriate Federal Agencies, e.g., Department of Homeland Security (DHS), the Department of Energy (DOE), Environmental Protection Agency (EPA), United States Coast Guard (USCG), Department of Defense (DOD), Department of Justice (DOJ), Department of Agriculture (USDA), and Nuclear Regulatory Commission (NRC). The Federal response to emergencies has been refined and improved over the last thirty years and has been tested on natural disasters (e.g. hurricanes and floods), man-made disasters (oil spills), and terrorist events (9/11). However, the system has never been tested under an actual RDD event. Drills have been conducted with Federal, State, and local agencies to examine the initial (early) phases of such an event (TopOff 2 and TopOff 4). The Planning Guidance for Protection and Recovery Following Radiological Dispersal Device (RDD) and Improvised Nuclear Device (IND) incidents issued by the Department of Homeland Security (DHS) in August 2008 has never been fully tested in an interagency exercise. Recently, another exercise called Empire 09 that was situated in Albany, New York was conducted. Empire 09 consists of 3 different exercises be held in May and June, 2009. The first exercise, May 2009, involved a table top exercise for phase 1 (0-48 hours) of the response to an RDD incident. In early June, a full-scale 3- day exercise was conducted for the mid-phase response (48 hours +). A few weeks later, a one day full-scale exercise was conducted for the late phase (recovery) response to an RDD event. The lessons learned from this study are not available as of June 30, 2009. The objective of this report is to review and summarize anticipated Federal and State response actions and the roles and responsibilities of various agencies (DHS, EPA, DOE, NY-DEP, NY-DEC) with respect to decontamination issues that would arise from a radiological dispersion device (RDD), e.g., dirty bomb attack. These issues arise in the late phase of the response (48 hours and beyond) after the area has been stabilized and forensic information has been obtained. Much of the information provided in this report is taken directly from published guidance that is readily available.
Dispersion engineering of high-Q silicon microresonators via thermal oxidation
Jiang, Wei C; Usechak, Nicholas G; Lin, Qiang
2014-01-01T23:59:59.000Z
We propose and demonstrate a convenient and sensitive technique for precise engineering of group-velocity dispersion in high-Q silicon microresonators. By accurately controlling the surface-oxidation thickness of silicon microdisk resonators, we are able to precisely manage the zero-dispersion wavelength while simultaneously further improving the high optical quality of our devices, with the optical Q close to a million. The demonstrated dispersion management allows us to achieve parametric generation with precisely engineerable emission wavelengths, which shows great potential for application in integrated silicon nonlinear and quantum photonics.
Two-loop massive scalar three-point function in a dispersive approach
Vladyslav Pauk; Marc Vanderhaeghen
2014-11-12T23:59:59.000Z
We present a dispersion relation formalism to calculate a massive scalar two-loop vertex function. Such calculation is of direct relevance in the evaluation of the hadronic light-by-light contribution to the muon's anomalous magnetic moment due to meson poles. The discontinuity of the two-loop diagram is obtained by a sum of two- and three-particle cut contributions, which involve a phase space integration over the physical intermediate states. The real part of the vertex function is subsequently reconstructed through evaluation of a dispersion integral. We explicitly demonstrate that the dispersive formalism yields exactly the same result as the direct two-loop calculation.
Self-similar pulse evolution in an all-normal-dispersion laser
Renninger, William H.; Chong, Andy; Wise, Frank W. [Department of Applied Physics, Cornell University, 212 Clark Hall, Ithaca, New York 14853 (United States)
2010-08-15T23:59:59.000Z
Parabolic amplifier similaritons are observed inside a normal-dispersion laser. The self-similar pulse is a local nonlinear attractor in the gain segment of the oscillator. The evolution in the laser exhibits large (20 times) spectral breathing, and the pulse chirp is less than the group-velocity dispersion of the cavity. All of these features are consistent with numerical simulations. The amplifier similariton evolution also yields practical features such as parabolic output pulses with high energies, and the shortest pulses to date from a normal-dispersion laser.
Optical tsunamis: shoaling of shallow water rogue waves in nonlinear fibers with normal dispersion
Wabnitz, Stefan
2013-01-01T23:59:59.000Z
In analogy with ocean waves running up towards the beach, shoaling of prechirped optical pulses may occur in the normal group-velocity dispersion regime of optical fibers. We present exact Riemann wave solutions of the optical shallow water equations and show that they agree remarkably well with the numerical solutions of the nonlinear Schr\\"odinger equation, at least up to the point where a vertical pulse front develops. We also reveal that extreme wave events or optical tsunamis may be generated in dispersion tapered fibers in the presence of higher-order dispersion.
Dispersion engineering of high-Q silicon microresonators via thermal oxidation
Jiang, Wei C. [Institute of Optics, University of Rochester, Rochester, New York 14627 (United States); Zhang, Jidong [Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York 14627 (United States); Usechak, Nicholas G. [Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States); Lin, Qiang, E-mail: qiang.lin@rochester.edu [Institute of Optics, University of Rochester, Rochester, New York 14627 (United States); Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York 14627 (United States)
2014-07-21T23:59:59.000Z
We propose and demonstrate a convenient and sensitive technique for precise engineering of group-velocity dispersion in high-Q silicon microresonators. By accurately controlling the surface-oxidation thickness of silicon microdisk resonators, we are able to precisely manage the zero-dispersion wavelength, while simultaneously further improving the high optical quality of our devices, with the optical Q close to a million. The demonstrated dispersion management allows us to achieve parametric generation with precisely engineerable emission wavelengths, which shows great potential for application in integrated silicon nonlinear and quantum photonics.
Chertkov, Michael; Gabitov, Ildar
2004-03-02T23:59:59.000Z
The present invention provides methods and optical fibers for periodically pinning an actual (random) accumulated chromatic dispersion of an optical fiber to a predicted accumulated dispersion of the fiber through relatively simple modifications of fiber-optic manufacturing methods or retrofitting of existing fibers. If the pinning occurs with sufficient frequency (at a distance less than or are equal to a correlation scale), pulse degradation resulting from random chromatic dispersion is minimized. Alternatively, pinning may occur quasi-periodically, i.e., the pinning distance is distributed between approximately zero and approximately two to three times the correlation scale.
On the application of computational fluid dynamics codes for liquefied natural gas dispersion.
Luketa-Hanlin, Anay Josephine; Koopman, Ronald P. (Lawrence Livermore National Laboratory, Livermore, CA); Ermak, Donald (Lawrence Livermore National Laboratory, Livermore, CA)
2006-02-01T23:59:59.000Z
Computational fluid dynamics (CFD) codes are increasingly being used in the liquefied natural gas (LNG) industry to predict natural gas dispersion distances. This paper addresses several issues regarding the use of CFD for LNG dispersion such as specification of the domain, grid, boundary and initial conditions. A description of the k-{var_epsilon} model is presented, along with modifications required for atmospheric flows. Validation issues pertaining to the experimental data from the Burro, Coyote, and Falcon series of LNG dispersion experiments are also discussed. A description of the atmosphere is provided as well as discussion on the inclusion of the Coriolis force to model very large LNG spills.
Shinozuka, Masanobu
GIS-Based Hazardous Gas Dispersion, Simulations and Analysis Debasis Karmakar, Samit Ray Chaudhuri methodology to be developed for hazardous gas dispersion connecting Disaster Simulation and Trace with GIS of Gas Dispersion Affected Area Overlaid on Satellite Image (using ArcGIS 9.2) Scenario-based Simulation
Paris-Limouzy, Claire B.
Dispersants on the Subsea Oil Transport Claire B. Paris,*, Matthieu Le Henaff,, Zachary M. Aman,§ Ajit assessment of the potential effect of the dispersant on the subsea-to-surface oil partition. We adapted blowouts and on gauging the subsea use of synthetic dispersant in mitigating coastal damage. INTRODUCTION
Li, Tim
Tropical Cyclogenesis Associated with Rossby Wave Energy Dispersion of a Preexisting Typhoon. Part with the Rossby wave energy dispersion of a preexisting TC. The wave trains are oriented in a northwest induced by tropical cyclone (TC) energy dispersion are revealed based on the Quick Scatterometer (Quik
Maruyama, Shigeo
were dispersed well after the addition of methanol (up to 70 %) for a long time. These properties of the dispersants have alkyl chain or aromatic groups that show strong affinity for SWNTs. These functional groups and methanol) and solid states. The observed properties of the resulting dispersions are unique and different
Alternating projections on manifolds
2006-07-27T23:59:59.000Z
Jul 27, 2006 ... The survey ar- ticle [BB96] covers ... ?School of Operations Research and Industrial Engineering, Cornell University, Ithaca,. NY 14853, U.S.A. ...
Rehman, Abdul
2012-02-14T23:59:59.000Z
This thesis provides a detailed evaluation of different environmentally friendly dispersants in invert-emulsion drilling fluids that can be used to drill wells under difficult conditions such as HPHT. The drilling fluid is weighted by manganese...
Shear wave attenuation and dispersion in melt-bearing olivine polycrystals
interpretation and seismological implications Ulrich H. Faul, John D. Fitz Gerald, and Ian Jackson Research: seismic wave attenuation, olivine, partial melting, grain boundary sliding, grain boundary structure and dispersion in melt-bearing olivine polycrystals: 2. Microstructural interpretation and seismological