Trailing edge modifications for flatback airfoils.
Kahn, Daniel L. (University of California, Davis, CA); van Dam, C.P. (University of California, Davis, CA); Berg, Dale E.
2008-03-01T23:59:59.000Z
The adoption of blunt trailing edge airfoils (also called flatback airfoils) for the inboard region of large wind turbine blades has been proposed. Blunt trailing edge airfoils would not only provide a number of structural benefits, such as increased structural volume and ease of fabrication and handling, but they have also been found to improve the lift characteristics of thick airfoils. Therefore, the incorporation of blunt trailing edge airfoils would allow blade designers to more freely address the structural demands without having to sacrifice aerodynamic performance. These airfoils do have the disadvantage of generating high levels of drag as a result of the low-pressure steady or periodic flow in the near-wake of the blunt trailing edge. Although for rotors, the drag penalty appears secondary to the lift enhancement produced by the blunt trailing edge, high drag levels are of concern in terms of the negative effect on the torque and power generated by the rotor. Hence, devices are sought that mitigate the drag of these airfoils. This report summarizes the literature on bluff body vortex shedding and bluff body drag reduction devices and proposes four devices for further study in the wind tunnel.
Trailing Edge Noise Model Applied to Wind Turbine Airfoils
In order to increase public acceptance of wind energy in the coming years, there is a strong need Bertagnolio Title: Trailing Edge Noise Model Applied to Wind Turbine Airfoils Department: Wind EnergyTrailing Edge Noise Model Applied to Wind Turbine Airfoils Franck Bertagnolio Risř-R-1633(EN) Risř
Partially turbulated trailing edge cooling passages for gas turbine nozzles
Thatcher, Jonathan Carl (Schenectady, NY); Burdgick, Steven Sebastian (Schenectady, NY)
2001-01-01T23:59:59.000Z
A plurality of passages are spaced one from the other along the length of a trailing edge of a nozzle vane in a gas turbine. The passages lie in communication with a cavity in the vane for flowing cooling air from the cavity through the passages through the tip of the trailing edge into the hot gas path. Each passage is partially turbulated and includes ribs in an aft portion thereof to provide enhanced cooling effects adjacent the tip of the trailing edge. The major portions of the passages are smooth bore. By this arrangement, reduced temperature gradients across the trailing edge metal are provided. Additionally, the inlets to each of the passages have a restriction whereby a reduced magnitude of compressor bleed discharge air is utilized for trailing edge cooling purposes.
Load Alleviation through Adaptive Trailing Edge Control Surfaces: ADAPWING Overview
to investigate the potential of using adaptive trailing edge geometry on wind turbine blades as load alleviation field experienced by wind turbine blades is turbulent which causes fluctuating loads during nor- mal for the wind turbine industry if the alleviation systems do not add considerable extra cost. Recent work has
Survey of techniques for reduction of wind turbine blade trailing edge noise.
Barone, Matthew Franklin
2011-08-01T23:59:59.000Z
Aerodynamic noise from wind turbine rotors leads to constraints in both rotor design and turbine siting. The primary source of aerodynamic noise on wind turbine rotors is the interaction of turbulent boundary layers on the blades with the blade trailing edges. This report surveys concepts that have been proposed for trailing edge noise reduction, with emphasis on concepts that have been tested at either sub-scale or full-scale. These concepts include trailing edge serrations, low-noise airfoil designs, trailing edge brushes, and porous trailing edges. The demonstrated noise reductions of these concepts are cited, along with their impacts on aerodynamic performance. An assessment is made of future research opportunities in trailing edge noise reduction for wind turbine rotors.
Effects of trailing edge flap dynamic deployment on blade-vortex interactions
Nelson, Carter T.
1997-01-01T23:59:59.000Z
code based on potential flow theory with provisions for deformable geometry to incorporate a trailing edge flap. Experimental tests were conducted using a 2-D wind tunnel setup incorporating a pressure instrumented airfoil section with a deployable 20...
Augmentation of Power Output of Axisymmetric Ducted Wind Turbines by Porous Trailing Edge Disks
widnall, sheila
2014-06-30T23:59:59.000Z
This paper presents analytical and experimental results that demonstrated that the power output from a ducted wind turbine can be dramatically increased by the addition of a trailing edge device such as a porous disk. In ...
ORIGINAL ARTICLE An experimental investigation on the trailing edge cooling of
Hu, Hui
well beyond the maximum endurable temperature of the turbine blade material. As a result, hot gasORIGINAL ARTICLE An experimental investigation on the trailing edge cooling of turbine blades edge cooling; Wall slot jets; Turbine blades; Steroscopic particle image velocimetry (PIV) measurements
Hu, Hui
wall. In the present study, while air flow was supplied to simulate the hot main stream, the cooling Edge Cooling of Turbine Blades by using PIV and PSP Techniques Zifeng Yang1 and Hui Hu2 () Department to study the flow characteristics of the wall jets exiting from the trailing edge cooling slots
Heat transfer in the trailing edge cooling channels of turbine blades
Kumaran, T. K.
1989-01-01T23:59:59.000Z
Foundation and from the funded research contract (RF5810) through Dr. Han. NOMENCLATURE A area of heat transfer in the pin fin channel AI, area of heat transfer in the long ejection segments Az cross-sectional area, of trailing edge ejection holes A..., ?minimum flow cross-sectional area in the pin fin channel C'~ discharge coefficient Cp specific heat of air 1 diameter of trailing edge ejection holes D diameter of pins f overall friction factor h?heat transfer coefficient in the n th segment...
Study of Trailing-Edge Cooling Using Pressure Sensitive Paint Technique
Hu, Hui
Study of Trailing-Edge Cooling Using Pressure Sensitive Paint Technique Zifeng Yang and Hui Hu Iowa caused the turbine blades to be critical components to protect. Without an appropriate cooling technique regions on turbine blades, several cooling techniques, such as internal convective cooling and film
Liu, Yao-Hsien
2009-05-15T23:59:59.000Z
The gas turbine blade/vane internal cooling is achieved by circulating the compressed air through the cooling passages inside the turbine blade. Leading edge and trailing edge of the turbine blade are two critical regions which need to be properly...
An experimental investigation of turbine blade heat transfer and turbine blade trailing edge cooling
Choi, Jungho
2005-02-17T23:59:59.000Z
and turbulence intensity, respectively. The cascade inlet Reynolds number based on blade chord length was varied from 15,700 to 105,000, and the Strouhal number was varied from 0 to 2.96 by changing the rotating wake passing frequency (rod speed) and cascade... on the trailing edge (m) d rotating rod diameter e rib height h local heat transfer coefficient ( K2 ) k thermal conductivity of air at C (0.02598 mKW /) M Blowing ratio ( m c V V ) N RPM of rotating rod Nu local Nusselt number based on blade...
Hawkins, Brian
2014-05-31T23:59:59.000Z
Paper Trails is an exhibition consisting of two animations, Inquisitive Vignettes and Traces. These animations, one of which is projected on and accompanied by a player piano, examine the creation and interpretation of our ...
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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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin Transition in2, 2003Tool ofTopo II:7.1TrackingTrails Â» Trails List
Sun, Jing
2007-09-17T23:59:59.000Z
-link capacitor is one of the largest because it should keep the output voltage with low ripple. Also, the size of this capacitor is penalized due to the universal line voltage application. Synchronization through employing leading edge modulation for the first...
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Plan 5th Annual Report for FY 2011 (pdf) Trails Management Program Mitigation Action Plan 4th Annual Report for FY 2010 (pdf) General Background Trails Use Survey Summary The...
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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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin Transition in2, 2003Tool ofTopo II:7.1TrackingTrails Â» Trails
The Patrick Elvander Taxonomy Trail
California at Santa Cruz, University of
Patrick Elvander Taxonomy Trail The Patrick Elvander Taxonomy Trail at the Arboretum at UC Santa: Taxonomy is partly the study of the naming and clas- sification of plants. For this more technical to produce a preview edition of the Manual in 1989. By establishing this Taxonomy trail as a memorial, we
Trail, Tamara; Hysmith, Larry; Harmel-Garza, Denise
2001-08-03T23:59:59.000Z
Hunter education is most successful when it includes hands-on teaching about hunting and firearms safety. The Hunter Skills Trail is a proven technique for training both adults and young people, and this guide explains how to set up and conduct...
Boundary element simulation of oscillating foil with leading-edge separation
Dong, Xiaoxia, S.M. Massachusetts Institute of Technology
2007-01-01T23:59:59.000Z
In this thesis, we develop a numerical model to account for the leading-edge separation for the boundary element simulation of the oscillating foil with potential flow assumption. Similar to the trailing-edge separation, ...
Normal Scalar Curvature Inequalities Normal Scalar Curvature
Lu, Zhiqin
Scalar Curvature Inequalities Introduction In 1999, De Smet, Dillen, Verstraelen and Vrancken (DDVV, F. Dillen, L. Verstraelen, and L. Vrancken, A pointwise inequality in submanifold theory, Arch. Math
Spatial arrangement of trail markers and visitor involvement on a self-guided interpretive trail
Marcy, Julie Benedict
1982-01-01T23:59:59.000Z
Interest to Visitors. 9 39. Being Close to Nature as a Trail Use Motivation. 99 40. Enjoying the Scenery as a Trail Use Motivation. 99 41 Seeing New and Different Things as a Trail Use Motivation 100 42. Learning More as a Trail Use Mot. ivation. 100... and Leaflet Box. . . 7. Visitor Center Adjacent to Trail. 33 33 8, Visitor Participation on the Trail l. . 9. Visitor Participation on the Trail 2. . 10. Visitor Participation on the Trail 3. . 57 57 59 Er. vironmental Impact Incurred Along...
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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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening a solidSynthesis of 2D AlloysTrails Taking Care of our Trails
JEPSON PRAIRIE Self Guided Nature Trail
Ferrara, Katherine W.
's inhabitants and visitors, please remain on the trail, and leave your pets. No smoking is allowed. The trail in western North America, from Alaska to Mexico. Explanations for the origins of these mounds include
Wind turbine trailing-edge aerodynamic brake design
Quandt, G.
1996-01-01T23:59:59.000Z
This report describes the design of a centrifugally actuated aerodynamic-overspeed device for a horizontal-axis wind turbine. The device will meet the following criteria; (1) It will be effective for airfoil angles of attack 0{degrees} to 45{degrees}. (2) It will be stowed inside the blade profile prior to deployment. (3) It will be capable of offsetting the positive torque produced by the overall blade. (4) Hinge moments will be minimized to lower actuator loads and cost. (5) It will be evaluated as a potential power modulating active rotor-control system. A literature review of aerodynamic braking devices was conducted. Information from the literature review was used to conceptualize the most effective devices for subsequent testing and design. Wind-tunnel test data for several braking devices are presented in this report. Using the data for the most promising configuration, a preliminary design was developed for a MICON 65/13 wind turbine with Phoenix 7.9-m rotor blades.
Sandia Energy - Experiment for Improved Modeling of Trailing-Edge
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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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Scienceand RequirementsCoatingsUltra-High-Voltage SiliconEnergy CouncilEnergyShedding Noise
Settler's Trail | 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 onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f < RAPIDâ€Ž |Rippey JumpAir JumpCaliforniaGroup LLCSettler's Trail Jump
Chon, Jin Hyung
2005-08-29T23:59:59.000Z
that viewed two urban greenway trail corridors. Each trail had three treatments including the existing trail condition, a manipulated trail condition, and a reverse in direction of the existing trail condition. Analyses were conducted to 1) identify...
Spatial arrangement of trail markers and visitor involvement on a self-guided interpretive trail
Marcy, Julie Benedict
1982-01-01T23:59:59.000Z
be presented by asking "what constitutes an effective SGT in terms of visitor involvement with t'ne trail, leaflet suggestions, and the spacing of stakes or markers on the trail?" An effecrive program or technique is one which achieves its desired... concluded with open-ended questions on suggested improvements for the trail and leaflet. Sontag (27) states rhat there are three main ccmponents of t. rail evaluation: personal objeccive evaluation, observing visitor reaction, and questionnaires...
Stochastic Curvature Driven Flows 1 Motion by Mean Curvature
Stochastic Curvature Driven Flows. Nung Kwan Yip ..... controls the noise in regions of extreme temperature values. .... Control and Optimization, 31(1993), No.
Curvature Capillary Migration of Microspheres
Nima Sharifi-Mood; Iris B. Liu; Kathleen J. Stebe
2015-05-11T23:59:59.000Z
We address the question: How does capillarity propel microspheres along curvature gradients? For a particle on a fluid interface, there are two conditions that can apply at the three phase contact line: Either the contact line adopts an equilibrium contact angle, or it can be pinned by kinetic trapping, e.g. at chemical heterogeneities, asperities or other pinning sites on the particle surface. We formulate the curvature capillary energy for both scenarios for particles smaller than the capillary length and far from any pinning boundaries. The scale and range of the distortion made by the particle are set by the particle radius; we use singular perturbation methods to find the distortions and to rigorously evaluate the associated capillary energies. For particles with equilibrium contact angles, contrary to the literature, we find that the capillary energy is negligible, with the first contribution bounded to fourth order in the product of the particle radius and the deviatoric curvature. For pinned contact lines, we find curvature capillary energies that are finite, with a functional form investigated previously by us for disks and microcylinders on curved interfaces. In experiments, we show microsphere migrate along deterministic trajectories toward regions of maximum deviatoric curvature with curvature capillary energies ranging from $6 \\times10^3 - 5 \\times 10^4~k_BT$. These data agree with the curvature capillary energy for the case of pinned contact lines. The underlying physics of this migration is a coupling of the interface deviatoric curvature with the quadrupolar mode of nanometric disturbances in the interface owing to the particle's contact line undulations. This work is an example of the major implications of nanometric roughness and contact line pinning for colloidal dynamics.
Evolution of curvature invariants and lifting integrability
Kamp, Peter H. van der
Evolution of curvature invariants and lifting integrability Elizabeth L. Mansfield and Peter H. van. These define the curvature and evolution invariants that are associated to curves moving in the given geometry. The syzygy between the curvature and evolution invariants is obtained as a zero curvature relation
On the Weyl curvature hypothesis
Stoica, Ovidiu Cristinel, E-mail: holotronix@gmail.com
2013-11-15T23:59:59.000Z
The Weyl curvature hypothesis of Penrose attempts to explain the high homogeneity and isotropy, and the very low entropy of the early universe, by conjecturing the vanishing of the Weyl tensor at the Big-Bang singularity. In previous papers it has been proposed an equivalent form of Einstein’s equation, which extends it and remains valid at an important class of singularities (including in particular the Schwarzschild, FLRW, and isotropic singularities). Here it is shown that if the Big-Bang singularity is from this class, it also satisfies the Weyl curvature hypothesis. As an application, we study a very general example of cosmological models, which generalizes the FLRW model by dropping the isotropy and homogeneity constraints. This model also generalizes isotropic singularities, and a class of singularities occurring in Bianchi cosmologies. We show that the Big-Bang singularity of this model is of the type under consideration, and satisfies therefore the Weyl curvature hypothesis. -- Highlights: •The singularities we introduce are described by finite geometric/physical objects. •Our singularities have smooth Riemann and Weyl curvatures. •We show they satisfy Penrose’s Weyl curvature hypothesis (Weyl=0 at singularities). •Examples: FLRW, isotropic singularities, an extension of Schwarzschild’s metric. •Example: a large class of singularities which may be anisotropic and inhomogeneous.
Spatial curvature falsifies eternal inflation
Kleban, Matthew; Schillo, Marjorie, E-mail: mk161@nyu.edu, E-mail: mls604@nyu.edu [Center for Cosmology and Particle Physics, New York University, 4 Washington Place, New York (United States)
2012-06-01T23:59:59.000Z
Inflation creates large-scale cosmological density perturbations that are characterized by an isotropic, homogeneous, and Gaussian random distribution about a locally flat background. Even in a flat universe, the spatial curvature measured within one Hubble volume receives contributions from long wavelength perturbations, and will not in general be zero. These same perturbations determine the Cosmic Microwave Background (CMB) temperature fluctuations, which are O(10{sup ?5}). Consequently, the low-l multipole moments in the CMB temperature map predict the value of the measured spatial curvature ?{sub k}. On this basis we argue that a measurement of |?{sub k}| > 10{sup ?4} would rule out slow-roll eternal inflation in our past with high confidence, while a measurement of ?{sub k} < ?10{sup ?4} (which is positive curvature, a locally closed universe) rules out false-vacuum eternal inflation as well, at the same confidence level. In other words, negative curvature (a locally open universe) is consistent with false-vacuum eternal inflation but not with slow-roll eternal inflation, and positive curvature falsifies both. Near-future experiments will dramatically extend the sensitivity of ?{sub k} measurements and constitute a sharp test of these predictions.
Oregon Trail Wind Park | 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 onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, searchOfRoseConcernsCompany Oil andOpenEITODOOregon PublicTrail Wind Park Jump
R:\\Groups\\ENVIRO\\Work Requests\\2010\\Misc\\100101_Eastshore Trail...
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ENVIROWork Requests2010Misc100101Eastshore Trail100101Eastshore Trail Construction CX.docx Western Area Power Administration Sierra Nevada Region CATEGORICAL...
"Surface Curvature from Laser Triangulation Data" ELECTRICAL &
Goodman, James R.
"Surface Curvature from Laser Triangulation Data" John Rugis ELECTRICAL & COMPUTER ENGINEERING #12 for curvature calculations? #12;Display results on a 2D rectangular grid? Squashed dot mapping. #12;Results
Mirror with thermally controlled radius of curvature
Neil, George R.; Shinn, Michelle D.
2010-06-22T23:59:59.000Z
A radius of curvature controlled mirror for controlling precisely the focal point of a laser beam or other light beam. The radius of curvature controlled mirror provides nearly spherical distortion of the mirror in response to differential expansion between the front and rear surfaces of the mirror. The radius of curvature controlled mirror compensates for changes in other optical components due to heating or other physical changes. The radius of curvature controlled mirror includes an arrangement for adjusting the temperature of the front surface and separately adjusting the temperature of the rear surface to control the radius of curvature. The temperature adjustment arrangements can include cooling channels within the mirror body or convection of a gas upon the surface of the mirror. A control system controls the differential expansion between the front and rear surfaces to achieve the desired radius of curvature.
Kepler Problem in the Constant Curvature Space
G. Pronko
2007-06-04T23:59:59.000Z
We present algebraic derivation of the result of Schr\\"{o}dinger [1] for the spectrum of hydrogen atom in the space with constant curvature.
Wright, Lesley Mae
2009-06-02T23:59:59.000Z
The present work has been an experimental investigation to evaluate the applicability of gas turbine cooling technology. With the temperature of the mainstream gas entering the turbine elevated above the melting temperature of the metal components...
Radius of curvature controlled mirror
Neil, George R.; Rathke, John Wickham; Schultheiss, Thomas John; Shinn, Michelle D.; Dillon-Townes, Lawrence A.
2006-01-17T23:59:59.000Z
A controlled radius of curvature mirror assembly comprising: a distortable mirror having a reflective surface and a rear surface; and in descending order from the rear surface; a counter-distortion plate; a flow diverter having a flow diverter aperture at the center thereof; a flow return plate having a flow return aperture at the center thereof; a thermal isolation plate having a thermal isolation plate aperture at the center thereof and a flexible heater having a rear surface and a flexible heater aperture at the center thereof; a double walled tube defining a coolant feed chamber and a coolant return chamber; said coolant feed chamber extending to and through the flow diverter aperture and terminating at the counter-distortion plate and the coolant return chamber extending to and through the thermal isolation backplate and terminating at the flow diverter; and a coolant feed and a coolant return exit at the rear of said flexible heater.
Ricci Curvature of the Internet Topology
Ni, Chien-Chun; Gao, Jie; Gu, Xianfeng David; Saucan, Emil
2015-01-01T23:59:59.000Z
Analysis of Internet topologies has shown that the Internet topology has negative curvature, measured by Gromov's "thin triangle condition", which is tightly related to core congestion and route reliability. In this work we analyze the discrete Ricci curvature of the Internet, defined by Ollivier, Lin, etc. Ricci curvature measures whether local distances diverge or converge. It is a more local measure which allows us to understand the distribution of curvatures in the network. We show by various Internet data sets that the distribution of Ricci cuvature is spread out, suggesting the network topology to be non-homogenous. We also show that the Ricci curvature has interesting connections to both local measures such as node degree and clustering coefficient, global measures such as betweenness centrality and network connectivity, as well as auxilary attributes such as geographical distances. These observations add to the richness of geometric structures in complex network theory.
Gao, Dengliang
2013-03-01T23:59:59.000Z
In 3D seismic interpretation, curvature is a popular attribute that depicts the geometry of seismic reflectors and has been widely used to detect faults in the subsurface; however, it provides only part of the solutions to subsurface structure analysis. This study extends the curvature algorithm to a new curvature gradient algorithm, and integrates both algorithms for fracture detection using a 3D seismic test data set over Teapot Dome (Wyoming). In fractured reservoirs at Teapot Dome known to be formed by tectonic folding and faulting, curvature helps define the crestal portion of the reservoirs that is associated with strong seismic amplitude and high oil productivity. In contrast, curvature gradient helps better define the regional northwest-trending and the cross-regional northeast-trending lineaments that are associated with weak seismic amplitude and low oil productivity. In concert with previous reports from image logs, cores, and outcrops, the current study based on an integrated seismic curvature and curvature gradient analysis suggests that curvature might help define areas of enhanced potential to form tensile fractures, whereas curvature gradient might help define zones of enhanced potential to develop shear fractures. In certain fractured reservoirs such as at Teapot Dome where faulting and fault-related folding contribute dominantly to the formation and evolution of fractures, curvature and curvature gradient attributes can be potentially applied to differentiate fracture mode, to predict fracture intensity and orientation, to detect fracture volume and connectivity, and to model fracture networks.
Generalized Strong Curvature Singularities and Cosmic Censorship
W. Rudnicki; R. J. Budzynski; W. Kondracki
2002-03-19T23:59:59.000Z
A new definition of a strong curvature singularity is proposed. This definition is motivated by the definitions given by Tipler and Krolak, but is significantly different and more general. All causal geodesics terminating at these new singularities, which we call generalized strong curvature singularities, are classified into three possible types; the classification is based on certain relations between the curvature strength of the singularities and the causal structure in their neighborhood. A cosmic censorship theorem is formulated and proved which shows that only one class of generalized strong curvature singularities, corresponding to a single type of geodesics according to our classification, can be naked. Implications of this result for the cosmic censorship hypothesis are indicated.
Stratigraphic statistical curvature analysis techniques
Bengtson, C.A.; Ziagos, J.P.
1987-05-01T23:59:59.000Z
SCAT applies statistical techniques to dipmeter data to identify patterns of bulk curvature, determine transverse and longitudinal structural directions, and reconstruct cross sections and contour maps. STRAT-SCAT applies the same concepts to geometric interpretation of multistoried unimodal, bimodal, or trough-type cross-bedding and also to seismic stratigraphy-scale stratigraphic structures. Structural dip, which comprises the bulk of dipmeter data, is related to beds that (statistically) were deposited with horizontal attitudes; stratigraphic dip is related to beds that were deposited with preferentially oriented nonhorizontal attitudes or to beds that assumed such attitudes because of differential compaction. Stratigraphic dip generates local zones of departure from structural dip on special SCAT plots. The RMS (root-mean-square) of apparent structural dip is greatest in the (structural) T-direction and least in the perpendicular L-direction; the RMS of stratigraphic dip (measured with respect to structural dip) is greatest in the stratigraphic T*-direction and least in the stratigraphic L*-direction. Multistoried, cross-bedding appears on T*-plots as local zones of either greater scatter or statistically significant departure of stratigraphic median dip from structural dip. In contrast, the L*-plot (except for trough-type cross-bedding) is sensitive to cross-bedding. Seismic stratigraphy-scale depositional sequences are identified on Mercator dip versus azimuth plots and polar tangent plots as secondary cylindrical-fold patterns imposed on global structural patterns. Progradational sequences generate local cycloid-type patterns on T*-plots, and compactional sequences generate local cycloid-type patterns on T*-plots, and compactional sequences generate local half-cusp patterns. Both features, however, show only structural dip on L*-plots.
Curvature invariants in type-III spacetimes
V. Pravda
1999-08-17T23:59:59.000Z
The results of paper [1] are generalized for vacuum type-III solutions with, in general, a non-vanishing cosmological constant Lambda. It is shown that all curvature invariants containing derivatives of the Weyl tensor vanish if a type-III spacetime admits a non-expanding and non-twisting null geodesic congruence. A non-vanishing curvature invariant containing first derivatives of the Weyl tensor is found in the case of type-III spacetime with expansion or twist.
Holographic Superconductors and Higher Curvature Corrections
Massimo Siani
2011-11-14T23:59:59.000Z
We study a fully backreacted holographic model of a four-dimensional superconductor by including a higher curvature interaction in the bulk action. We study how the critical temperature and the field theory condensate vary in this model and conclude that positive higher curvature couplings make the condensation harder. We also compute the conductivity, finding significant deviations from the conjectured universal frequency gap to critical temperature ratio.
Audit Trails in the Aeolus Distributed Security Victoria Popic
Audit Trails in the Aeolus Distributed Security Platform by Victoria Popic B.S., C.S. and Math MIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Department of Electrical Engineering and Computer Science August 31, 2010 Certified by in the Aeolus Distributed Security Platform by Victoria Popic Submitted to the Department of Electrical
Evolution of isolated turbulent trailing vortices Karthik Duraisamy1,a
Alonso, Juan J.
Evolution of isolated turbulent trailing vortices Karthik Duraisamy1,a and Sanjiva K. Lele2,b 1 evolution of a low swirl-number turbulent Batchelor vortex is studied using pseudospectral direct numerical application of boundary conditions. The physics of the evolution is investigated with an emphasis
Prellberg, Thomas
of three-dimensional lattice trails Andrea Bedini* and Aleksander L. Owczarek Department of Mathematics
Curvature constraints from the causal entropic principle
Bozek, Brandon; Albrecht, Andreas; Phillips, Daniel [Physics Department, University of California, Davis, One Shields Avenue, Davis, California 95616-8677 (United States)
2009-07-15T23:59:59.000Z
Current cosmological observations indicate a preference for a cosmological constant that is drastically smaller than what can be explained by conventional particle physics. The causal entropic principle (Bousso et al.) provides an alternative approach to anthropic attempts to predict our observed value of the cosmological constant by calculating the entropy created within a causal diamond. We have extended this work to use the causal entropic principle to predict the preferred curvature within the 'multiverse'. We have found that values larger than {rho}{sub k}=40{rho}{sub m} are disfavored by more than 99.99% peak value at {rho}{sub {lambda}}=7.9x10{sup -123} and {rho}{sub k}=4.3{rho}{sub m} for open universes. For universes that allow only positive curvature or both positive and negative curvature, we find a correlation between curvature and dark energy that leads to an extended region of preferred values. Our universe is found to be disfavored to an extent depending on the priors on curvature. We also provide a comparison to previous anthropic constraints on open universes and discuss future directions for this work.
RESEARCH PAPER Interaction of edge influence from multiple edges: examples
Macdonald, Ellen
) in harvested forest landscapes could impair, or possibly enhance, their effectiveness. When multiple edges of cutblocks (harvested areas) and water bodies were entered into the models to predict edge influence) positive interaction, observed edge influence is greater than from either edge alone; (3) negative
Curvature radiation in pulsar magnetospheric plasma
Janusz Gil; Yuri Lyubarsky; George I. Melikidze
2003-10-21T23:59:59.000Z
We consider the curvature radiation of the point-like charge moving relativistically along curved magnetic field lines through a pulsar magnetospheric electron-positron plasma. We demonstrate that the radiation power is largely suppressed as compared with the vacuum case, but still at a considerable level, high enough to explain the observed pulsar luminosities. The emitted radiation is polarized perpendicularly to the plane of the curved magnetic filed lines coincides with $ which can freely escape from the magnetospheric plasma. Our results strongly support the coherent curvature radiation by the spark-associated solitons as a plausible mechanism of pulsar radio emission.
Energy definition for quadratic curvature gravities
Ahmet Baykal
2012-12-03T23:59:59.000Z
A conserved current for generic quadratic curvature gravitational models is defined, and it is shown that, at the linearized level, it corresponds to the Deser-Tekin charges. An explicit expression for the charge for new massive gravity in three dimensions is given. Some implications of the linearized equations are discussed.
Space-time Curvature of Classical Electromagnetism
R. W. M. Woodside
2004-10-08T23:59:59.000Z
The space-time curvature carried by electromagnetic fields is discovered and a new unification of geometry and electromagnetism is found. Curvature is invariant under charge reversal symmetry. Electromagnetic field equations are examined with De Rham co homology theory. Radiative electromagnetic fields must be exact and co exact to preclude unobserved massless topological charges. Weyl's conformal tensor, here called ``the gravitational field'', is decomposed into a divergence-free non-local piece with support everywhere and a local piece with the same support as the matter. By tuning a local gravitational field to a Maxwell field the electromagnetic field's local gravitational field is discovered. This gravitational field carries the electromagnetic field's polarization or phase information, unlike Maxwell's stress-energy tensor. The unification assumes Einstein's equations and derives Maxwell's equations from curvature assumptions. Gravity forbids magnetic monopoles! This unification is stronger than the Einstein-Maxwell equations alone, as those equations must produce the electromagnetic field's local gravitational field and not just any conformal tensor. Charged black holes are examples. Curvature of radiative null electromagnetic fields is characterized.
CUTTING EDGE Cutting Edge: Dendritic Cells Copulsed with Microbial and
Maizels, Rick
CUTTING EDGE IMMUNOLOGY THE OF JOURNAL Cutting Edge: Dendritic Cells Copulsed with Microbial). However, there is evidence that DC-associated factors other than IL-12 also play a significant role in Th1
CUTTING EDGE Cutting Edge: Treatment of Complement Regulatory
Ponder, Katherine P.
CUTTING EDGE IMMUNOLOGY THE OF JOURNAL Cutting Edge: Treatment of Complement Regulatory Protein attachment of C regulators such as the decay-accelerating factor (DAF) (11) and C receptor 1-related gene
Oregon Trail El Cons Coop, Inc | 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 onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluatingGroup |JilinLuOpenNorthOlympia GreenThe communityOrchid BioenergyOregon Trail
Cosmological Signatures of Anisotropic Spatial Curvature
Pereira, Thiago S; Carneiro, Saulo
2015-01-01T23:59:59.000Z
If one is willing to give up the cherished hypothesis of spatial isotropy, many interesting cosmological models can be developed beyond the simple anisotropically expanding scenarios. One interesting possibility is presented by shear-free models in which the anisotropy emerges at the level of the curvature of the homogeneous spatial sections, whereas the expansion is dictated by a single scale factor. We show that such models represent viable alternatives to describe the large-scale structure of the inflationary universe, leading to a kinematically equivalent Sachs-Wolfe effect. Through the definition of a complete set of spatial eigenfunctions we compute the two-point correlation function of scalar perturbations in these models. In addition, we show how such scenarios would modify the spectrum of the CMB assuming that the observations take place in a small patch of a universe with anisotropic curvature.
Curvature perturbation spectrum from false vacuum inflation
Gong, Jinn-Ouk [Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706-1390 (United States)] [Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706-1390 (United States); Sasaki, Misao [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)] [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)
2009-01-15T23:59:59.000Z
In the inflationary cosmology it occurs frequently that the inflaton field is trapped in a local, transient minimum with non-zero vacuum energy. The difficulty regarding the curvature perturbation produced during such a stage is that classically the inflaton does not move so that the comoving hypersurfaces are not well defined at linear order in the scalar field perturbation. In this paper, assuming a mechanism of trapping which resembles a high temperature correction to the potential, we explicitly calculate for the first time the resulting power spectrum of the curvature perturbation by evaluating the quantum two-point correlation function directly. The spectrum is steeply blue with the spectral index n{sub R} = 4.
Curvature perturbation spectrum from false vacuum inflation
Jinn-Ouk Gong; Misao Sasaki
2008-11-17T23:59:59.000Z
In the inflationary cosmology it occurs frequently that the inflaton field is trapped in a local, transient minimum with non-zero vacuum energy. The difficulty regarding the curvature perturbation produced during such a stage is that classically the inflaton does not move so that the comoving hypersurfaces are not well defined at linear order in the scalar field perturbation. In this paper, assuming a mechanism of trapping which resembles a high temperature correction to the potential, we explicitly calculate for the first time the resulting power spectrum of the curvature perturbation by evaluating the quantum two-point correlation function directly. The spectrum is steeply blue with the spectral index n_R = 4.
Curvature perturbation spectrum from false vacuum inflation
Gong, Jinn-Ouk [Department of Physics, University of Wisconsin-Madison 1150 University Avenue, Madison, WI 53706-1390 (United States)
2008-11-23T23:59:59.000Z
In the inflationary cosmology it occurs frequently that the inflaton field is trapped in a local, transient minimum with non-zero vacuum energy. The difficulty regarding the curvature perturbation produced during such a stage is that classically the inflaton does not move so that the comoving hypersurfaces are not well defined at linear order in the scalar field perturbation. In this paper, assuming a mechanism of trapping which resembles a high temperature correction to the potential, we explicitly calculate for the first time the resulting power spectrum of the curvature perturbation by evaluating the quantum two-point correlation function directly. The spectrum is steeply blue with the spectral index n{sub R} = 4.
Curvature Dependence of Hydrophobic Hydration Dynamics
R. Gregor Weiß; Matthias Heyden; Joachim Dzubiella
2015-04-08T23:59:59.000Z
We investigate the curvature-dependence of water dynamics in the vicinity of hydrophobic spherical solutes using molecular dynamics simulations. For both, the lateral and perpendicular diffusivity as well as for H-bond kinetics of water in the first hydration shell, we find a non-monotonic solute-size dependence, exhibiting extrema close to the well-known structural crossover length scale for hydrophobic hydration. Additionally, we find an apparently anomalous diffusion for water moving parallel to the surface of small solutes, which, however, can be explained by topology effects. The intimate connection between solute curvature, water structure and dynamics has implications for our understanding of hydration dynamics at heterogeneous biomolecular surfaces.
General Notion of Curvature in Catastrophe Theory Terms
Nikolov, Petko; Ruseva, Gergana
2008-01-01T23:59:59.000Z
We introduce a new notion of a curvature of a superconnection, different from the one obtained by a purely algebraic analogy with the curvature of a linear connection. The naturalness of this new notion of a curvature of a superconnection comes from the study of singularities of smooth sections of vector bundles (Catastrophe Theory). We demonstrate that the classical examples of obstructions to a local equivalence: exterior differential for 2-forms, Riemannian tensor, Weil tensor, curvature of a linear connection and Nijenhuis tensor can be treated in terms of one general approach. This approach, applied to the superconnection leads to a new notion of a curvature (proposed in this paper) of a superconnection.
General Notion of Curvature in Catastrophe Theory Terms
Petko Nikolov; Lora Nikolova; Gergana Ruseva
2008-02-15T23:59:59.000Z
We introduce a new notion of a curvature of a superconnection, different from the one obtained by a purely algebraic analogy with the curvature of a linear connection. The naturalness of this new notion of a curvature of a superconnection comes from the study of singularities of smooth sections of vector bundles (Catastrophe Theory). We demonstrate that the classical examples of obstructions to a local equivalence: exterior differential for 2-forms, Riemannian tensor, Weil tensor, curvature of a linear connection and Nijenhuis tensor can be treated in terms of one general approach. This approach, applied to the superconnection leads to a new notion of a curvature (proposed in this paper) of a superconnection.
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.
Superintegrable systems on spaces of constant curvature
Gonera, Cezary, E-mail: cgonera@uni.lodz.pl; Kaszubska, Magdalena
2014-07-15T23:59:59.000Z
Construction and classification of two-dimensional (2D) superintegrable systems (i.e. systems admitting, in addition to two global integrals of motion guaranteeing the Liouville integrability, the third global and independent one) defined on 2D spaces of constant curvature and separable in the so-called geodesic polar coordinates are presented. The method proposed is applicable to any value of curvature including the case of Euclidean plane, sphere and hyperbolic plane. The main result is a generalization of Bertrand’s theorem on 2D spaces of constant curvature and covers most of the known separable and superintegrable models on such spaces (in particular, the so-called Tremblay–Turbiner–Winternitz (TTW) and Post–Winternitz (PW) models which have recently attracted some interest). -- Highlights: •Classifying 2D superintegrable, separable (polar coordinates) systems on S{sup 2}, R{sup 2}, H{sup 2}. •Construction of radial, angular potentials leading to superintegrability. •Generalization of Bertrand’s theorem covering known models, e.g. Higgs, TTW, PW, and Coulomb.
Softening of edges of solids by surface tension
Serge Mora; Yves Pomeau
2014-08-10T23:59:59.000Z
Surface tension tends to minimize the area of interfaces between pieces of matter in different thermodynamic phases, be they in the solid or the liquid state. This can be relevant for the macroscopic shape of very soft solids, and lead to a roughening of initially sharp edges. We calculate this effect for a neo-Hookean elastic solid, with assumptions corresponding to actual experiments, namely the case where an initially sharp edge is rounded by the effect of surface tension felt when the fluid surrounding the soft solid (and so surface tension) is changed at the solid/liquid boundary. We consider two opposite limits where the analysis can be carried to the end, the one of a shallow angle and the one of a very sharp angle. Both cases yield a discontinuity of curvature in the state with surface tension although the initial state had a discontinuous slope.
North Carolina at Chapel Hill, University of
rectangular yellow LED indicators which flash rapidly in a wig-wag sequence. It is solar-powered, radio controlled, and activated by trail users. The experimental design was to collect data of trail users before of more benefit would be periodic police enforcement operations, or the development of a passive system
Trans-Pecos Wagon Trail Tour West Texas Historical Association Annual Meeting
Rock, Chris
Trans-Pecos Wagon Trail Tour West Texas Historical Association Annual Meeting April 3, 2014, Odessa, Texas. Historically it was major landmark on the trail west as one of a few fordable sections of the Pecos in West Texas, and as a first source of water for about 75 miles on the wagon and stage route from
Observations of Edge Turbulence
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for RenewableSpeeding accessSpeeding access(SC)Gas and OilPhaseObservation ofEdge
The Bounded L2 Curvature Conjecture
Sergiu Klainerman; Igor Rodnianski; Jeremie Szeftel
2014-10-10T23:59:59.000Z
This is the main paper in a sequence in which we give a complete proof of the bounded $L^2$ curvature conjecture. More precisely we show that the time of existence of a classical solution to the Einstein-vacuum equations depends only on the $L^2$-norm of the curvature and a lower bound on the volume radius of the corresponding initial data set. We note that though the result is not optimal with respect to the standard scaling of the Einstein equations, it is nevertheless critical with respect to its causal geometry. Indeed, $L^2$ bounds on the curvature is the minimum requirement necessary to obtain lower bounds on the radius of injectivity of causal boundaries. We note also that, while the first nontrivial improvements for well posedness for quasilinear hyperbolic systems in spacetime dimensions greater than 1+1 (based on Strichartz estimates) were obtained in [Ba-Ch1] [Ba-Ch2] [Ta1] [Ta2] [Kl-R1] and optimized in [Kl-R2] [Sm-Ta], the result we present here is the first in which the full structure of the quasilinear hyperbolic system, not just its principal part, plays a crucial role. To achieve our goals we recast the Einstein vacuum equations as a quasilinear $so(3,1)$-valued Yang-Mills theory and introduce a Coulomb type gauge condition in which the equations exhibit a specific new type of \\textit{null structure} compatible with the quasilinear, covariant nature of the equations. To prove the conjecture we formulate and establish bilinear and trilinear estimates on rough backgrounds which allow us to make use of that crucial structure. These require a careful construction and control of parametrices including $L^2$ error bounds which is carried out in [Sz1]-[Sz4], as well as a proof of sharp Strichartz estimates for the wave equation on a rough background which is carried out in \\cite{Sz5}.
Amplification of curvature perturbations in cyclic cosmology
Zhang Jun; Liu Zhiguo; Piao Yunsong [College of Physical Sciences, Graduate School of Chinese Academy of Sciences, Beijing 100049 (China)
2010-12-15T23:59:59.000Z
We analytically and numerically show that through the cycles with nonsingular bounce, the amplitude of curvature perturbation on a large scale will be amplified and the power spectrum will redden. In some sense, this amplification will eventually destroy the homogeneity of the background, which will lead to the ultimate end of cycles of the global universe. We argue that for the model with increasing cycles, it might be possible that a fissiparous multiverse will emerge after one or several cycles, in which the cycles will continue only at corresponding local regions.
Hubbard, Susan
, California Savannah River National Laboratory (SRNL), Aiken, South Carolina *S Supporting Information Timeframes: The F-Area Savannah River Site Jiamin Wan,, * Tetsu K. Tokunaga, Wenming Dong, Miles E. Denham, and Susan S. Hubbard Earth Sciences Division, Lawrence Berkeley National Laboratory (LBNL), Berkeley
Liu, Yao-Hsien
2009-05-15T23:59:59.000Z
Crossflow for (a) Smooth Surface and (b) Ribbed Surface............................................... 24 8 Tapered Rib Configuration......................................................................... 26 9 Schematics of the Wedge-Shaped Test... Condition without Crossflow Effect .......................................................... 77 xiv Page 32 Secondary Flow Induced by the Rotation and Ribs inside the Channel .... 79 33 Nusselt Number for Ribbed Channel at Stationary Condition...
River Edge Redevelopment Zone (Illinois)
Broader source: Energy.gov [DOE]
The purpose of the River Edge Redevelopment Program is to revive and redevelop environmentally challenged properties adjacent to rivers in Illinois.
CUTTING EDGE Cutting Edge: Essential Role of Hypoxia Inducible
Nizet, Victor
CUTTING EDGE IMMUNOLOGY THE OF JOURNAL Cutting Edge: Essential Role of Hypoxia Inducible Factor-1 raises the level of the transcriptional regu- lator hypoxia-inducible factor-1 (HIF-1 ) in macro- phages recently identified novel and essential roles of the transcriptional regulator hypox- ia-inducible factor
Glenn Seaborg Trail | U.S. DOE Office of Science (SC)
Office of Science (SC) Website
the forest. This central portion of the trail is a low spot blanketed with a lush bed of New York ferns and Christmas ferns, giving the area a very verdant appearance and a feeling...
An Archaeological Survey for the Turkey Creek Trail Project in Brazos County, Texas
Moore, William
2015-07-15T23:59:59.000Z
Recreation Trails grant administered by the Texas Parks and Wildlife Service. To be eligible, the applicant competed with numerous public entities and non-profit corporations. Grantees were selected on need and services provided. The area examined consisted...
On 3 October 2012 a heavily trailed ITV documentary branded Sir Jimmy Savile as a
Anderson, Jim
On 3 October 2012 a heavily trailed ITV documentary branded Sir Jimmy Savile as a manipulative for the BBC. UNIVERSITY OF Southampton Institute of Criminal Justice Research Scandal Without End: Sir Jimmy
Poster No.: 169 Sulci and Curvature: Detection of the Roof
Paris-Sud XI, Université de
Poster No.: 169 Sulci and Curvature: Detection of the Roof Christophe Renault, Michel Desvignes] used the superficial trace of sulci, we detect the roof of the sulci, which presents less intersection the curvature K1 et K2 are equal. Results We have presented a method to extract roof of sulci with a sub
Curvature Dependency of Surface Tension in Multicomponent Systems
Firoozabadi, Abbas
Curvature Dependency of Surface Tension in Multicomponent Systems Erik Santiso Dept. of Chemical InterScience (www.interscience.wiley.com). The effect of curvature on the surface tension of droplets for multicomponent systems, the relation between the surface tension at the surface of tension and the distance
De Santo, Robert James William
1972-01-01T23:59:59.000Z
A DYNAMIC STABILITY ANALYSIS OF AN AIRCRAFT PASSING THROUGH THE TRAILING VORTICES OF ANOTHER AIRCRAFT A Thesi~ x ROBERT J. MAE SANTO, JR. Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE December 1972 Major Subject: Aerospace Engineering A DYNAMIC STABILITY ANALYSIS OF AN AIRCRAFT PASSING THROUGH THE TRAILING VORTICES OF ANOTHER AIRCRAFT A Thesis by ROBERT J. W. DE SANTO) JR. Approved as to style...
Effects of plasma shape and profiles on edge stability in DIII-D
Lao, L.L.; Chan, V.S. [General Atomics, San Diego, CA (United States); Chen, L. [Academia Sinica, Beijing (China). Inst. of Plasma Physics] [and others
1998-12-01T23:59:59.000Z
The results of recent experimental and theoretical studies concerning the effects of plasma shape and current and pressure profiles on edge instabilities in DIII-D are presented. Magnetic oscillations with toroidal mode number n {approx} 2--9 and a fast growth time {gamma}{sup {minus}1} = 20--150 {micro}s are often observed prior to the first giant type 1 ELM in discharges with moderate squareness. High n ideal ballooning second stability access encourages edge instabilities by facilitating the buildup of the edge pressure gradient and bootstrap current density which destabilize the intermediate to low n modes. Analysis suggests that discharges with large edge pressure gradient and bootstrap current density are more unstable to n > 1 modes. Calculations and experimental results show that ELM amplitude and frequency can be varied by controlling access to the second ballooning stability regime at the edge through variation of the squareness of the discharge shape. A new method is proposed to control edge instabilities by reducing access to the second ballooning stability regime at the edge using high order local perturbation of the plasma shape in the outboard bad curvature region.
On 3-gauge transformations, 3-curvatures, and Gray-categories
Wang, Wei, E-mail: wwang@zju.edu.cn [Department of Mathematics, Zhejiang University, Zhejiang 310027 (China)] [Department of Mathematics, Zhejiang University, Zhejiang 310027 (China)
2014-04-15T23:59:59.000Z
In the 3-gauge theory, a 3-connection is given by a 1-form A valued in the Lie algebra g, a 2-form B valued in the Lie algebra h, and a 3-form C valued in the Lie algebra l, where (g,h,l) constitutes a differential 2-crossed module. We give the 3-gauge transformations from one 3-connection to another, and show the transformation formulae of the 1-curvature 2-form, the 2-curvature 3-form, and the 3-curvature 4-form. The gauge configurations can be interpreted as smooth Gray-functors between two Gray 3-groupoids: the path 3-groupoid P{sub 3}(X) and the 3-gauge group G{sup L} associated to the 2-crossed module L, whose differential is (g,h,l). The derivatives of Gray-functors are 3-connections, and the derivatives of lax-natural transformations between two such Gray-functors are 3-gauge transformations. We give the 3-dimensional holonomy, the lattice version of the 3-curvature, whose derivative gives the 3-curvature 4-form. The covariance of 3-curvatures easily follows from this construction. This Gray-categorical construction explains why 3-gauge transformations and 3-curvatures have the given forms. The interchanging 3-arrows are responsible for the appearance of terms with the Peiffer commutator (, )
Analytic torsion, vortices and positive Ricci curvature
Berman, Robert J
2010-01-01T23:59:59.000Z
We characterize the global maximizers of a certain non-local functional defined on the space of all positively curved metrics on an ample line bundle L over a Kahler manifold X. This functional is an adjoint version, introduced by Berndtsson, of Donaldson's L-functional and generalizes the Ding-Tian functional whose critical points are Kahler-Einstein metrics of positive Ricci curvature. Applications to (1) analytic torsions on Fano manifolds (2) Chern-Simons-Higgs vortices on tori and (3) Kahler geometry are given. In particular, proofs of conjectures of (1) Gillet-Soul\\'e and Fang (concerning the regularized determinant of Dolbeault Laplacians on the two-sphere) (2) Tarantello and (3) Aubin (concerning Moser-Trudinger type inequalities) in these three settings are obtained. New proofs of some results in Kahler geometry are also obtained, including a lower bound on Mabuchi's K-energy and the uniqueness result for Kahler-Einstein metrics on Fano manifolds of Bando-Mabuchi. This paper is a substantially extend...
Estimating type curve parameters with the cumulative curvature method
Harris, Dan Edward
1986-01-01T23:59:59.000Z
curvature of Ramey type curves at a forward span of 40'$ . 32 15 Cumulative curvature of Ramey type curves at a forward span of 50$ . 33 16 Cumulative curvature of Ramey type curves at a forward span of 60$ 34 ix LIST OF FIGURES icontinued) 17..."wand spans ranging f;om 15$ to 60$ are presented in Figure 10 through 12. Since data that bately reaches past the end of the unit slope region is too vague even for this technique, the graph with a forward span of 0$ to 15$ is omitied here because...
Edge equilibrium code for tokamaks
Li, Xujing [Institute of Computational Mathematics and Scientific/Engineering Computing, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, P.O. Box 2719, Beijing 100190 (China)] [Institute of Computational Mathematics and Scientific/Engineering Computing, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, P.O. Box 2719, Beijing 100190 (China); Zakharov, Leonid E. [Princeton Plasma Physics Laboratory Princeton, MS-27 P.O. Box 451, New Jersey (United States)] [Princeton Plasma Physics Laboratory Princeton, MS-27 P.O. Box 451, New Jersey (United States); Drozdov, Vladimir V. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)] [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)
2014-01-15T23:59:59.000Z
The edge equilibrium code (EEC) described in this paper is developed for simulations of the near edge plasma using the finite element method. It solves the Grad-Shafranov equation in toroidal coordinate and uses adaptive grids aligned with magnetic field lines. Hermite finite elements are chosen for the numerical scheme. A fast Newton scheme which is the same as implemented in the equilibrium and stability code (ESC) is applied here to adjust the grids.
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 Initial Value Problem Using Metric and Extrinsic Curvature
James W. York
2004-05-01T23:59:59.000Z
The initial value problem is introduced after a thorough review of the essential geometry. The initial value equations are put into elliptic form using both conformal transformations and a treatment of the extrinsic curvature introduced recently. This use of the metric and the extrinsic curvature is manifestly equivalent to the author's conformal thin sandwich formulation. Therefore, the reformulation of the constraints as an elliptic system by use of conformal techniques is complete.
Curvature driven acceleration : a utopia or a reality ?
Sudipta Das; Narayan Banerjee; Naresh Dadhich
2005-07-23T23:59:59.000Z
The present work shows that a combination of nonlinear contribution from the Ricci curvature in Einstein field equations can drive a late time acceleration of expansion of the universe. The transit from the decelerated to the accelerated phase of expansion takes place smoothly without having to resort to a study of asymptotic behaviour. This result emphasizes the need for thorough and critical examination of models with nonlinear contribution from the curvature.
Fermion localization and flavour hierarchy in higher curvature spacetime
Choudhury, Sayantan; SenGupta, Soumitra
2015-01-01T23:59:59.000Z
Fermion localization in a braneworld model in presence of dilaton coupled higher curvature Gauss-Bonnet bulk gravity is discussed. It is shown that the left handed fermionic modes can be localized on the visible brane due to the dilaton coupled higher curvature term without the necessity of any external localizing bulk field. This offers a natural resolution of the flavour hierarchy problem in Standard Model.
No Large Scale Curvature Perturbations during Waterfall of Hybrid Inflation
Ali Akbar Abolhasani; Hassan Firouzjahi
2011-01-18T23:59:59.000Z
In this paper the possibility of generating large scale curvature perturbations induced from the entropic perturbations during the waterfall phase transition of standard hybrid inflation model is studied. We show that whether or not appreciable amounts of large scale curvature perturbations are produced during the waterfall phase transition depend crucially on the competition between the classical and the quantum mechanical back-reactions to terminate inflation. If one considers only the classical evolution of the system we show that the highly blue-tilted entropy perturbations induce highly blue-tilted large scale curvature perturbations during the waterfall phase transition which dominate over the original adiabatic curvature perturbations. However, we show that the quantum back-reactions of the waterfall field inhomogeneities produced during the phase transition dominate completely over the classical back-reactions. The cumulative quantum back-reactions of very small scales tachyonic modes terminate inflation very efficiently and shut off the curvature perturbations evolution during the waterfall phase transition. This indicates that the standard hybrid inflation model is safe under large scale curvature perturbations during the waterfall phase transition.
Anomalous radial transport in tokamak edge plasma
Bodi, Vasudeva Raghavendra Kowsik
2010-01-01T23:59:59.000Z
Transport in tokamak plasma . . . . . . . . . . . . . . .Numerical simulations of tokamak plasma . . . . . . . . .of blobs in tokamak edge plasmas . . . . . . . . . . . . . .
Magnetic Edge States in Graphene
Gabriela Murguia
2010-08-29T23:59:59.000Z
Magnetic confinement in graphene has been of recent and growing interest because its potential applications in nanotechnology. In particular, the observation of the so called magnetic edge states in graphene has opened the possibility to deepen into the generation of spin currents and its applications in spintronics. We study the magnetic edge states of quasi-particles arising in graphene monolayers due to an inhomogeneous magnetic field of a magnetic barrier in the formalism of the two-dimensional massless Dirac equation. We also show how the solutions of such states in each of both triangular sublattices of the graphene are related through a supersymmetric transformation in the quantum mechanical sense.
Ramirez, Amado
1971-01-01T23:59:59.000Z
a trailing vortex system of a larger aircraft. This analysis, based on a lifting surface theory developed by Jones and Rao, neglects wing-body-tail interaction effects. The changes in the aerodynamic loads and moments on the De Havilland Beaver..., to the trailing vortex system. The response of the Beaver aircraft in longitudinal flight is predicted as it penetrates a trailing vortex system of known strength. The trailing vortex strength is chosen in such a way that the linear- ization assumption...
is critically important in the translocation of death receptor to the cell surface. Moreover, sodium arsenite and further down-regulates cFLIP levels in melanoma cells. We have evaluated the effects of sequentialSequential Treatment by Ionizing Radiation and Sodium Arsenite Dramatically Accelerates TRAIL
Imaging of lithium pellet ablation trails and measurement of g profiles in TFTR
Garnier, Darren T.
Imaging of lithium pellet ablation trails and measurement of g profiles in TFTR J. L. Terry, E. S March 1992) Video images with 2 ps exposures of the Li+ emission in Li pellet ablation clouds have been obtained in a variety of Tokamak Fusion Test Reactor tokamak discharges. The pellet clouds are viewed from
A Bold and Fearless Rider: Ed Miller and the Paper Trail
Stratton, John M.
2002-11-01T23:59:59.000Z
This article recounts and summarizes the various published reports that discuss the death of 18-year old Ed Miller on the Santa Fe Trail in present-day McPherson County, Kansas, in July, 1864. The author attempts to confirm the actual date of death...
Lyapunov exponents and phase diagrams reveal multi-factorial control over TRAIL-induced apoptosis
Lyapunov exponents and phase diagrams reveal multi-factorial control over TRAIL-induced apoptosis). Here, we investigate factors controlling type I versus II phenotypes by performing Lyapunov exponent-or-none control over activation of effector caspases. Thus, phase diagrams derived from Lyapunov exponent analysis
Fermi Normal Coordinates and Fermion Curvature Couplings in General Relativity
Anshuman Dey; Abhisek Samanta; Tapobrata Sarkar
2014-03-18T23:59:59.000Z
We study gravitational curvature effects in circular and radial geodesics in static, spherically symmetric space-times, using Fermi normal coordinates. We first set up these coordinates in the general case, and then use this to study effective magnetic fields due to gravitational curvature in the exterior and interior Schwarzschild, Janis-Newman-Winicour, and Bertrand space-times. We show that these fields can be large for specific parameter values in the theories, and thus might have observational significance. We discuss the qualitative differences of the magnetic field for vacuum space-times and for those seeded by matter. We estimate the magnitude of these fields in realistic galactic scenarios and discuss their possible experimental relevance. Gravitational curvature corrections to the Hydrogen atom spectrum for these space-times are also discussed briefly.
Energy Science and Technology Software Center (OSTI)
002099IBMPC00 MM-Estimator and Adjusted Super Smoother based Simultaneous Prediction Confedenc http://nature.berkeley.edu/vulpelab/loguinov/
Curvature radiation and giant subpulses in the Crab pulsar
Janusz Gil; George I. Melikidze
2003-11-07T23:59:59.000Z
It is argued that the nanosecond giant subpulses detected recently in the Crab pulsar are generated by means of the coherent curvature radiation of charged relativistic solitons associated with sparking discharges of the inner gap potential drop above the polar cap.
Probability Distribution of Curvatures of Isosurfaces in Gaussian Random Fields
Paulo R. S. Mendonca; Rahul Bhotika; James V. Miller
2007-05-15T23:59:59.000Z
An expression for the joint probability distribution of the principal curvatures at an arbitrary point in the ensemble of isosurfaces defined on isotropic Gaussian random fields on Rn is derived. The result is obtained by deriving symmetry properties of the ensemble of second derivative matrices of isotropic Gaussian random fields akin to those of the Gaussian orthogonal ensemble.
LYCEN 9721 May 1997 LOCAL NUCLEAR SLOPE and CURVATURE
Boyer, Edmond
LYCEN 9721 May 1997 LOCAL NUCLEAR SLOPE and CURVATURE in HIGH ENERGY pp and ÂŻpp ELASTIC SCATTERING The local nuclear slope B(s, t) = d dt ln dn(s,t) dt is reconstructed from the exper- imental angular agreement with the (non fitted) slope data, in particular for the evolution of B(s, t) with s as a function
Edge modes in band topological insulators
Lukasz Fidkowski; T. S. Jackson; Israel Klich
2011-05-09T23:59:59.000Z
We characterize gapless edge modes in translation invariant topological insulators. We show that the edge mode spectrum is a continuous deformation of the spectrum of a certain gluing function defining the occupied state bundle over the Brillouin zone (BZ). Topologically non-trivial gluing functions, corresponding to non-trivial bundles, then yield edge modes exhibiting spectral flow. We illustrate our results for the case of chiral edge states in two dimensional Chern insulators, as well as helical edges in quantum spin Hall states.
Absence of jamming in ant trails: Feedback control of self propulsion and noise
Chaudhuri, Debasish
2014-01-01T23:59:59.000Z
We present a model of ant traffic considering individual ants as self-propelled particles undergoing single file motion on a one-dimensional trail. Recent experiments on unidirectional ant traffic in well-formed natural trails showed that the collective velocity of ants remains approximately unchanged, leading to absence of jamming even at very high densities [ John et. al., Phys. Rev. Lett. 102, 108001 (2009) ]. Assuming a feedback control mechanism of self-propulsion force generated by each ant using information about the distance from the ant in front, our model captures all the main features observed in the experiment. The distance headway distribution shows a maximum corresponding to separations within clusters. The position of this maximum remains independent of average number density. We find a non-equilibrium first order transition, with the formation of an infinite cluster at a threshold density where all the ants in the system suddenly become part of a single cluster.
Sprinkle, J.K.; Hansen, W.J.
1993-02-11T23:59:59.000Z
In 1979, a K-edge densitometer (KED) was installed by the Safeguards Assay group from Los Alamos National Laboratory in the PNC reprocessing plant at Tokai-mura, Japan. It uses an active nondestructive assay technique, KED, to measure the plutonium concentration of the product solution. The measurement uncertainty of an assay depends on the count time chosen, but can be 0.5% or better. The computer hardware and software were upgraded in 1992. This manual describes the operation of the instrument, with an emphasis on the user interface to the software.
Clean Edge | 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 onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual Siteof EnergyInnovationin UrbanCity ofCityClean Economy Network Jump to: navigation,Edge
RELATION OF THE WAVE{PROPAGATION METRIC TENSOR TO THE CURVATURES
Cerveny, Vlastislav
RELATION OF THE WAVE{PROPAGATION METRIC TENSOR TO THE CURVATURES OF THE SLOWNESS AND RAY The contravariant components of the wave{propagation metric tensor equal half the second{order partial derivatives. The relations of the wave{ propagation metric tensor to the curvature matrix and Gaussian curvature
Graphene as a quantum surface with curvature-strain preserving dynamics
M. V. Karasev
2010-11-16T23:59:59.000Z
We discuss how the curvature and the strain density of the atomic lattice generate the quantization of graphene sheets as well as the dynamics of geometric quasiparticles propagating along the constant curvature/strain levels. The internal kinetic momentum of Riemannian oriented surface (a vector field preserving the Gaussian curvature and the area) is determined.
Curvature-based energy for simulation and variational modeling Denis Zorin
Mohri, Mehryar
Curvature-based energy for simulation and variational modeling Denis Zorin New York University 719 Broadway, 12th floor New York, New York, 10012 dzorin@mrl.nyu.edu Abstract Curvature-based energy unanswered. We discuss the general principles for defining curvature- based energy on discrete surfaces based
Self-avoiding trails with nearest neighbour interactions on the square lattice
A. Bedini; A. L. Owczarek; T. Prellberg
2012-10-26T23:59:59.000Z
Self-avoiding walks and self-avoiding trails, two models of a polymer coil in dilute solution, have been shown to be governed by the same universality class. On the other hand, self-avoiding walks interacting via nearest-neighbour contacts (ISAW) and self-avoiding trails interacting via multiply-visited sites (ISAT) are two models of the coil-globule, or collapse transition of a polymer in dilute solution. On the square lattice it has been established numerically that the collapse transition of each model lies in a different universality class. The models differ in two substantial ways. They differ in the types of subsets of random walk configurations utilised (site self-avoidance versus bond self-avoidance) and in the type of attractive interaction. It is therefore of some interest to consider self-avoiding trails interacting via nearest neighbour attraction (INNSAT) in order to ascertain the source for the difference in the collapse universality class. Using the flatPERM algorithm, we have performed computer simulations of this model. We present numerical evidence that the singularity in the free energy of INNSAT at the collapse transition has a similar exponent to that of the ISAW model rather than the ISAT model. This would indicate that the type of interaction used in ISAW and ISAT is the source of the difference in universality class.
PROBING CURVATURE EFFECTS IN THE FERMI GRB 110920
Shenoy, A.; Maximon, L. C.; Dhuga, K. S.; Parke, W. C.; Maclachlan, G. A.; Eskandarian, Ali [Department of Physics, The George Washington University, Washington, DC 20052 (United States); Sonbas, E. [Department of Physics, University of Adiyaman, 02040 Adiyaman (Turkey); Dermer, C. [Space Science Division, Code 7653, Naval Research Laboratory, Washington, DC 20375 (United States); Bhat, P. N. [CSPAR, University of Alabama in Huntsville, Huntsville, AL 35805 (United States); Hakkila, J. [Department of Physics and Astronomy, College of Charleston, Charleston, SC 29424 (United States); Ukwatta, T. N., E-mail: ashwinsp469@gmail.com [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States)
2013-11-20T23:59:59.000Z
Curvature effects in gamma-ray bursts (GRBs) have long been a source of considerable interest. In a collimated relativistic GRB jet, photons that are off-axis relative to the observer arrive at later times than on-axis photons and are also expected to be spectrally softer. In this work, we invoke a relatively simple kinematic two-shell collision model for a uniform jet profile and compare its predictions to GRB prompt-emission data for observations that have been attributed to curvature effects such as the peak-flux-peak-frequency relation, i.e., the relation between the ?F{sub ?} flux and the spectral peak, E{sub pk} in the decay phase of a GRB pulse, and spectral lags. In addition, we explore the behavior of pulse widths with energy. We present the case of the single-pulse Fermi GRB 110920 as a test for the predictions of the model against observations.
On the mass formula and Wigner and curvature energy terms
G. Royer
2007-10-12T23:59:59.000Z
The efficiency of different mass formulas derived from the liquid drop model including or not the curvature energy, the Wigner term and different powers of the relative neutron excess $I$ has been determined by a least square fitting procedure to the experimental atomic masses assuming a constant R$_{0,charge}$/A$^{1/3}$ ratio. The Wigner term and the curvature energy can be used independently to improve the accuracy of the mass formula. The different fits lead to a surface energy coefficient of around 17-18 MeV, a relative sharp charge radius r$_0$ of 1.22-1.23 fm and a proton form-factor correction to the Coulomb energy of around 0.9 MeV.
Curvature effects in carbon nanomaterials: Exohedral versus endohedral supercapacitors
Huang, Jingsong [ORNL; Sumpter, Bobby G [ORNL; Meunier, Vincent [ORNL; Gogotsi, Yury G. [Drexel University; Yushin, Gleb [Georgia Institute of Technology; Portet, Cristelle [Drexel University
2010-01-01T23:59:59.000Z
Capacitive energy storage mechanisms in nanoporous carbon supercapacitors hinge on endohedral interactions in carbon materials with macro-, meso-, and micropores that have negative surface curvature. In this article, we show that because of the positive curvature found in zero-dimensional carbon onions or one-dimensional carbon nanotube arrays, exohedral interactions cause the normalized capacitance to increase with decreasing particle size or tube diameter, in sharp contrast to the behavior of nanoporous carbon materials. This finding is in good agreement with the trend of recent experimental data. Our analysis suggests that electrical energy storage can be improved by exploiting the highly curved surfaces of carbon nanotube arrays with diameters on the order of 1 nm.
Curvature effects on carbon nanomaterials: Exohedral versus endhohedral supercapacitors
Huang, J.; Sumpter, B. G.; Meunier, V.; Yushin, G.; Portet, C.; Gogotsi, Y.
2010-01-01T23:59:59.000Z
Capacitive energy storage mechanisms in nanoporous carbon supercapacitors hinge on endohedral interactions in carbon materials with macro-, meso-, and micropores that have negative surface curvature. In this article, we show that because of the positive curvature found in zero-dimensional carbon onions or one-dimensional carbon nanotube arrays, exohedral interactions cause the normalized capacitance to increase with decreasing particle size or tube diameter, in sharp contrast to the behavior of nanoporous carbon materials. This finding is in good agreement with the trend of recent experimental data. Our analysis suggests that electrical energy storage can be improved by exploiting the highly curved surfaces of carbon nanotube arrays with diameters on the order of 1 nm.
Spatial curvature effects on molecular transport by diffusion
J. Balakrishnan
2003-08-25T23:59:59.000Z
For a substance diffusing on a curved surface, we obtain an explicit relation valid for very small values of the time, between the local concentration, the diffusion coefficient, the intrinsic spatial curvature and the time. We recover the known solution of Fick's law of diffusion in the flat space limit. In the biological context, this result would be useful in understanding the variations in the diffusion rates of integral proteins and other molecules on membranes.
Surface tension with Normal Curvature in Curved Space-Time
Himanshu kumar; Sharf Alam; Suhail Ahmad
2012-11-01T23:59:59.000Z
With an aim to include the contribution of surface tension in the action of the boundary, we define the tangential pressure in terms of surface tension and Normal curvature in a more naturally geometric way. First, we show that the negative tangential pressure is independent of the four-velocity of a very thin hyper-surface. Second, we relate the 3-pressure of a surface layer to the normal curvature and the surface tension. Third, we relate the surface tension to the energy of the surface layer. Four, we show that the delta like energy flows across the hyper-surface will be zero for such a representation of intrinsic 3-pressure. Five, for the weak field approximation and for static spherically symmetric configuration, we deduce the classical Kelvin's relation. Six, we write a modified action for the boundary having contributions both from surface tension and normal curvature of the surface layer. Also we propose a method to find the physical action assuming a reference background, where the background is not flat.
Research Frontiers Cutting-Edge Research
Takada, Shoji
Research Frontiers Cutting-Edge Research in Kyoto University Kyoto University is known. Some of them exhibit circularly polarized light (CPL) with unprecedented anisotropy factors: they emit
CUTTING EDGE Cutting Edge: Innate Immunity Conferred by B Cells Is
Hedrick, Stephen M.
CUTTING EDGE IMMUNOLOGY THE OF JOURNAL Cutting Edge: Innate Immunity Conferred by B Cells-specific Casp8-deficient mice. The activation of NF- B or IFN regulatory factor 3 was found to be unaffected
Meisam Asgari; Aisa Biria
2015-02-17T23:59:59.000Z
Lipid-bilayers are the fundamental constituents of the walls of most living cells and lipid vesicles, giving them shape and compartment. The formation and growing of pores in a lipid bilayer have attracted considerable attention from an energetic point of view in recent years. Such pores permit targeted delivery of drugs and genes to the cell, and regulate the concentration of various molecules within the cell. The formation of such pores is caused by various reasons such as changes in cell environment, mechanical stress or thermal fluctuations. Understanding the energy and elastic behaviour of a lipid-bilayer edge is crucial for controlling the formation and growth of such pores. In the present work, the interactions in the molecular level are used to obtain the free energy of the edge of an open lipid bilayer. The resulted free-energy density includes terms associated with flexural and torsional energies of the edge, in addition to a line-tension contribution. The line tension, elastic moduli, and spontaneous normal and geodesic curvatures of the edge are obtained as functions of molecular distribution, molecular dimensions, cutoff distance, and the interaction strength. These parameters are further analyzed by implementing a soft-core interaction potential in the microphysical model. The dependence of the elastic free-energy of the edge to the size of the pore is reinvestigated through an illustrative example, and the results are found to be in agreement with the previous observations.
Meisam Asgari; Aisa Biria
2015-04-05T23:59:59.000Z
Lipid-bilayers are the fundamental constituents of the walls of most living cells and lipid vesicles, giving them shape and compartment. The formation and growing of pores in a lipid bilayer have attracted considerable attention from an energetic point of view in recent years. Such pores permit targeted delivery of drugs and genes to the cell, and regulate the concentration of various molecules within the cell. The formation of such pores is caused by various reasons such as changes in cell environment, mechanical stress or thermal fluctuations. Understanding the energy and elastic behaviour of a lipid-bilayer edge is crucial for controlling the formation and growth of such pores. In the present work, the interactions in the molecular level are used to obtain the free energy of the edge of an open lipid bilayer. The resulted free-energy density includes terms associated with flexural and torsional energies of the edge, in addition to a line-tension contribution. The line tension, elastic moduli, and spontaneous normal and geodesic curvatures of the edge are obtained as functions of molecular distribution, molecular dimensions, cutoff distance, and the interaction strength. These parameters are further analyzed by implementing a soft-core interaction potential in the microphysical model. The dependence of the elastic free-energy of the edge to the size of the pore is reinvestigated through an illustrative example, and the results are found to be in agreement with the previous observations.
Annotated Bibliography of EDGE2D Use
J.D. Strachan and G. Corrigan
2005-06-24T23:59:59.000Z
This annotated bibliography is intended to help EDGE2D users, and particularly new users, find existing published literature that has used EDGE2D. Our idea is that a person can find existing studies which may relate to his intended use, as well as gain ideas about other possible applications by scanning the attached tables.
Time-saving Cutting-edge practice
Cai, Long
Pedigree Pioneering Longevity Time-saving Cutting-edge practice Superb teaching resources-based Dentistry Providing your institution with the perfect combination of pedigree, longevity, cutting-edge to 1999 Immediate impact: top 5 in immediacy index (June 2013)* Impact factor: 0.811** *Immediacy index
Anomalous critical behaviour in the polymer collapse transition of three-dimensional lattice trails
Andrea Bedini; Aleksander L Owczarek; Thomas Prellberg
2011-11-11T23:59:59.000Z
Trails (bond-avoiding walks) provide an alternative lattice model of polymers to self-avoiding walks, and adding self-interaction at multiply visited sites gives a model of polymer collapse. Recently, a two-dimensional model (triangular lattice) where doubly and triply visited sites are given different weights was shown to display a rich phase diagram with first and second order collapse separated by a multi-critical point. A kinetic growth process of trails (KGT) was conjectured to map precisely to this multi-critical point. Two types of low temperature phases, globule and crystal-like, were encountered. Here, we investigate the collapse properties of a similar extended model of interacting lattice trails on the simple cubic lattice with separate weights for doubly and triply visited sites. Again we find first and second order collapse transitions dependent on the relative sizes of the doubly and triply visited energies. However we find no evidence of a low temperature crystal-like phase with only the globular phase in existence. Intriguingly, when the ratio of the energies is precisely that which separates the first order from the second-order regions anomalous finite-sized scaling appears. At the finite size location of the rounded transition clear evidence exists for a first order transition that persists in the thermodynamic limit. This location moves as the length increases, with its limit apparently at the point that maps to a KGT. However, if one fixes the temperature to sit at exactly this KGT point then only a critical point can be deduced from the data. The resolution of this apparent contradiction lies in the breaking of crossover scaling and the difference in the shift and transition width (crossover) exponents.
Mixed lipid bilayers with locally varying spontaneous curvature and bending
Guillaume Gueguen; Nicolas Destainville; Manoel Manghi
2014-08-27T23:59:59.000Z
A model of lipid bilayers made of a mixture of two lipids with different average compositions on both leaflets, is developed. A Landau hamiltonian describing the lipid-lipid interactions on each leaflet, with two lipidic fields $\\psi_1$ and $\\psi_2$, is coupled to a Helfrich one, accounting for the membrane elasticity, via both a local spontaneous curvature, which varies as $C_0+C_1(\\psi_1-\\psi_2)/2$, and a bending modulus equal to $\\kappa_0+\\kappa_1(\\psi_1+\\psi_2)/2$. This model allows us to define curved patches as membrane domains where the asymmetry in composition, $\\psi_1-\\psi_2$, is large, and thick and stiff patches where $\\psi_1+\\psi_2$ is large. These thick patches are good candidates for being lipidic rafts, as observed in cell membranes, which are composed primarily of saturated lipids forming a liquid-ordered domain and are known to be thick and flat nano-domains. The lipid-lipid structure factors and correlation functions are computed for globally spherical membranes and planar ones. Phase diagrams are established, within a Gaussian approximation, showing the occurrence of two types of Structure Disordered phases, with correlations between either curved or thick patches, and an Ordered phase, corresponding to the divergence of the structure factor at a finite wave vector. The varying bending modulus plays a central role for curved membranes, where the driving force $\\kappa_1C_0^2$ is balanced by the line tension, to form raft domains of size ranging from 10 to 100~nm. For planar membranes, raft domains emerge via the cross-correlation with curved domains. A global picture emerges from curvature-induced mechanisms, described in the literature for planar membranes, to coupled curvature- and bending-induced mechanisms in curved membranes forming a closed vesicle.
Glenn Seaborg Trail | U.S. DOE Office of Science (SC)
Office of Science (SC) Website
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurTheBrookhaven NationalRegionalsResearch Â»FundingGlenn Seaborg Trail Basic Energy
Los Alamos science sleuth on the trail of a martian mystery
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |Is YourAwardspublicexceeds wasteNewScientistsMapTrail of a
Direct and alignment-insensitive measurement of cantilever curvature
Hermans, Rodolfo I.; Aeppli, Gabriel [London Centre for Nanotechnology, University College London, London (United Kingdom); Department of Physics and Astronomy, University College London, London (United Kingdom); Bailey, Joe M. [London Centre for Nanotechnology, University College London, London (United Kingdom); Centre for Mathematics and Physics in the Life Sciences and Experimental Biology, University College London, London (United Kingdom)
2013-07-15T23:59:59.000Z
We analytically derive and experimentally demonstrate a method for the simultaneous measurement of deflection for large arrays of cantilevers. The Fresnel diffraction patterns of a cantilever independently reveal tilt, curvature, cubic, and higher order bending of the cantilever. It provides a calibrated absolute measurement of the polynomial coefficients describing the cantilever shape, without careful alignment and could be applied to several cantilevers simultaneously with no added complexity. We show that the method is easily implemented, works in both liquid media and in air, for a broad range of displacements and is especially suited to the requirements for multi-marker biosensors.
Curvature and geometric modules of noncommutative spheres and tori
Arnlind, Joakim, E-mail: joakim.arnlind@liu.se [Department of Mathematics, Linköping University, 581 83 Linköping (Sweden)] [Department of Mathematics, Linköping University, 581 83 Linköping (Sweden)
2014-04-15T23:59:59.000Z
When considered as submanifolds of Euclidean space, the Riemannian geometry of the round sphere and the Clifford torus may be formulated in terms of Poisson algebraic expressions involving the embedding coordinates, and a central object is the projection operator, projecting tangent vectors in the ambient space onto the tangent space of the submanifold. In this note, we point out that there exist noncommutative analogues of these projection operators, which implies a very natural definition of noncommutative tangent spaces as particular projective modules. These modules carry an induced connection from Euclidean space, and we compute its scalar curvature.
Dark energy and dark matter as curvature effects
S. Capozziello; V. F. Cardone; A. Troisi
2006-03-20T23:59:59.000Z
Astrophysical observations are pointing out huge amounts of dark matter and dark energy needed to explain the observed large scale structures and cosmic accelerating expansion. Up to now, no experimental evidence has been found, at fundamental level, to explain such mysterious components. The problem could be completely reversed considering dark matter and dark energy as shortcomings of General Relativity and claiming for the correct theory of gravity as that derived by matching the largest number of observational data. As a result, accelerating behavior of cosmic fluid and rotation curves of spiral galaxies are reproduced by means of curvature effects.
Variational Problems which are Quadratic in the Surface Curvatures
Palmer, Bennett
of elasticity that grew out of Sophie Germain's original work on the Chladni plates. The other is the subject. In the early nineteenth century, the German physicist and amateur violinist Ernst Chladni presented a demonstration in which sand was sprinkled on metal plates. Chladni then played the edge of the plate with his
Curvature Wavefront Sensing for the Large Synoptic Survey Telescope
Xin, Bo; Liang, Ming; Chandrasekharan, Srinivasan; Angeli, George; Shipsey, Ian
2015-01-01T23:59:59.000Z
The Large Synoptic Survey Telescope (LSST) will use an active optics system (AOS) to maintain alignment and surface figure on its three large mirrors. Corrective actions fed to the LSST AOS are determined from information derived from 4 curvature wavefront sensors located at the corners of the focal plane. Each wavefront sensor is a split detector such that the halves are 1mm on either side of focus. In this paper we describe the extensions to published curvature wavefront sensing algorithms needed to address challenges presented by the LSST, namely the large central obscuration, the fast f/1.23 beam, off-axis pupil distortions, and vignetting at the sensor locations. We also describe corrections needed for the split sensors and the effects from the angular separation of different stars providing the intra- and extra-focal images. Lastly, we present simulations that demonstrate convergence, linearity, and negligible noise when compared to atmospheric effects when the algorithm extensions are applied to the LS...
Wan, J.
2013-01-01T23:59:59.000Z
and FSB-110D; Savannah River National Laboratory: Aiken, SC,Berkeley CA Savannah River National Laboratory (SRNL), Aiken
Sun, Jing
2007-09-17T23:59:59.000Z
AC/DC adapters mostly employ two-stage topology: Power Factor Correction (PFC) pre-regulation stage followed by an isolated DC/DC converter stage. Low power AC/DC adapters require a small size to be competitive. Among their components, the bulk DC...
Unknown
2011-09-05T23:59:59.000Z
During the past decade, the demand for clean renewable energy continues to rise drastically in Europe, the US, and other countries. Wind energy in the ocean can possibly be one of those future renewable clean energy sources as long...
Semi-flexible interacting self-avoiding trails on the square lattice
A Bedini; A L Owczarek; T Prellberg
2012-10-30T23:59:59.000Z
Self-avoiding walks self-interacting via nearest neighbours (ISAW) and self-avoiding trails interacting via multiply-visited sites (ISAT) are two models of the polymer collapse transition of a polymer in dilute solution. On the square lattice it has been established numerically that the collapse transition of each model lies in a different universality class. It has been shown that by adding stiffness to the ISAW model a second low temperature phase eventuates and a more complicated phase diagram ensues with three types of transition that meet at a multi-critical point. For large enough stiffness the collapse transition becomes first-order. Interestingly, a phase diagram of a similar structure has been seen to occur in an extended ISAT model on the triangular lattice without stiffness. It is therefore of interest to see the effect of adding stiffness to the ISAT model. We have studied by computer simulation a generalised model of self-interacting self-avoiding trails on the square lattice with a stiffness parameter added. Intriguingly, we find that stiffness does not change the order of the collapse transition for ISAT on the square lattice for a very wide range of stiffness weights. While at the lengths considered there are clear bimodal distributions for very large stiffness, our numerical evidence strongly suggests that these are simply finite-size effects associated with a crossover to a first-order phase transition at infinite stiffness.
Randall-Sundrum scenario with small curvature and dilepton production at LHC
Kisselev, A V
2013-01-01T23:59:59.000Z
The brief review of the recent results obtained in the Randall-Sundrum scenario with the small curvature of the five-dimensional space-time is presented.
North Carolina at Chapel Hill, University of
An Algorithm for Computing Customized 3D Printed Implants with Curvature Constrained Channels results in 3D printing and steerable needle motion planning to create customized implants containing
Revealing Burlington : Vermont architecture on the edge
Gates, Jeremy M., 1975-
2005-01-01T23:59:59.000Z
This project explores building in the most urban environment of a state that identifies with its ruralness. The site, located at the top of a steep bluff in Burlington at the edge between the city's downtown core and its ...
Development of the Astro Edge solar array
Spence, B.R.; Marks, G.W. [Astro Aerospace Corp., Carpinteria, CA (United States)
1994-12-31T23:59:59.000Z
The Astro Edge solar array is a new and innovative low concentrator power generating system which has been selected for CTA Incorporated`s NASA Small Spacecraft Technology Initiative (SSTI) program. Under the program, Astro will design, develop, produce and qualify two flight Astro Edge wings to support a July 1996 launch of the SSTI SmallSat dubbed ``CLARK``. The Astro Edge was selected as a new technology to benefit future NASA and commercial missions by providing high specific power, high stiffness, low risk, low stowed volume, reliability, light weight, and cost reduction features to meet the agency`s better, faster, cheaper goals. A brief program overview of design requirements, configuration, subsystem description, analysis, and planned testing of the SSTI Astro Edge solar array is discussed.
Neuronal Circuitry of the Local Edge Detector Retinal Ganglion Cell
Russell, Thomas Lee
2010-01-01T23:59:59.000Z
Rapid Narrow Luminance Changes……………………………………………………………………12responds selectively to luminance edges. But what neuronalto show that selectivity to luminance edges in the LED is
California: Cutting-Edge Biofuels Research and Entrepreneurship...
Office of Environmental Management (EM)
Cutting-Edge Biofuels Research and Entrepreneurship Provide a Proving Ground California: Cutting-Edge Biofuels Research and Entrepreneurship Provide a Proving Ground April 18, 2013...
Research Led by Sandia Reveals Leading-Edge Erosion Significantly...
Broader source: Energy.gov (indexed) [DOE]
Research Led by Sandia Reveals Leading-Edge Erosion Significantly Reduces Wind Turbine Performance Research Led by Sandia Reveals Leading-Edge Erosion Significantly Reduces Wind...
SUPERCONDUCTING TRANSITION EDGE BOLOMETER AND NOISE IN THIN FILMS
Yeh, Nan-Hsiung
2011-01-01T23:59:59.000Z
a) Composite Al superconducting bolometer (b) Composite SNSLBL-8019 SUPERCONDUCTING TRANSITION EDGE BOLOMETER AND INrights . LBL-8019 SUPERCONDUCTING TRANSITION EDGE BOLOMETER
Positive curvature property for some hypoelliptic heat kernels
Qian, Bin
2010-01-01T23:59:59.000Z
In this note, we look at some hypoelliptic operators arising from nilpotent rank 2 Lie algebras. In particular, we concentrate on the diffusion generated by three Brownian motions and their three L\\'evy areas, which is the simplest extension of the Laplacian on the Heisenberg group $\\mathbb{H}$. In order to study contraction properties of the heat kernel, we show that, as in the case of the Heisenberg group, the restriction of the sub-Laplace operator acting on radial functions (which are defined in some precise way in the core of the paper) satisfies a non negative Ricci curvature condition (more precisely a $CD(0, \\infty)$ inequality), whereas the operator itself does not satisfy any $CD(r,\\infty)$ inequality. From this we may deduce some useful, sharp gradient bounds for the associated heat kernel.
On the Possibility of Anisotropic Curvature in Cosmology
Tomi S. Koivisto; David F. Mota; Miguel Quartin; Tom G. Zlosnik
2010-11-22T23:59:59.000Z
In addition to shear and vorticity a homogeneous background may also exhibit anisotropic curvature. Here a class of spacetimes is shown to exist where the anisotropy is solely of the latter type, and the shear-free condition is supported by a canonical, massless 2-form field. Such spacetimes possess a preferred direction in the sky and at the same time a CMB which is isotropic at the background level. A distortion of the luminosity distances is derived and used to test the model against the CMB and supernovae (using the Union catalog), and it is concluded that the latter exhibit a higher-than-expected dependence on angular position. It is shown that future surveys could detect a possible preferred direction by observing ~ 20 / (\\Omega_{k0}^2) supernovae over the whole sky.
Decay of the Fourier transform of surfaces with vanishing curvature
Laszlo Erdos; Manfred Salmhofer
2006-04-18T23:59:59.000Z
We prove $L^p$-bounds on the Fourier transform of measures $\\mu$ supported on two dimensional surfaces. Our method allows to consider surfaces whose Gauss curvature vanishes on a one-dimensional submanifold. Under a certain non-degeneracy condition, we prove that $\\wh\\mu\\in L^{4+\\beta}$, $\\beta>0$, and we give a logarithmically divergent bound on the $L^4$-norm. We use this latter bound to estimate almost singular integrals involving the dispersion relation, $e(p)= \\sum_1^3 [1-\\cos p_j]$, of the discrete Laplace operator on the cubic lattice. We briefly explain our motivation for this bound originating in the theory of random Schr\\"odinger operators.
Li, Xiaolin "Andy"
battery life, energy saving is of paramount importance in the design of sensor network protocols. Recent transmission path is greatly shortened and energy consumption for relaying is reduced. However, data gatheringTrailing Mobile Sinks: A Proactive Data Reporting Protocol for Wireless Sensor Networks Xinxin Liu
Abbeel, Pieter
, bevel-tip medical needles, planning curvature-constrained channels in 3D printed implants for targeted for perturbations. Our ap- proach can also be used for designing optimized channel layouts within 3D printed is the design of multiple bounded curvature channels in intracavitary 3D printed im- plants through which
Friction and curvature judgement Chris Christou (1) and Alan Wing (2)
Friction and curvature judgement Chris Christou (1) and Alan Wing (2) (1) Optometry resistance to motion due to friction. This resistance creates a force vector which varies in direction with friction. But the vector also varies in direction with the curvature of the surface traversed by the finger
Curvature-Dependent Surface Tension of a Growing Droplet Michael P. Moody and Phil Attard
Attard, Phil
Curvature-Dependent Surface Tension of a Growing Droplet Michael P. Moody and Phil Attard School-vapor interfaces. It is shown that the surface tension decreases approximately linearly with the supersaturation ratio and that it vanishes at the spinodal. The effect leads to a curvature-dependent surface tension
Classification of Hamilton-Jacobi separation in orthogonal coordinates with diagonal curvature
Rajaratnam, Krishan, E-mail: k2rajara@uwaterloo.ca; McLenaghan, Raymond G., E-mail: rgmclenaghan@uwaterloo.ca [Department of Applied Mathematics, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)
2014-08-15T23:59:59.000Z
We find all orthogonal metrics where the geodesic Hamilton-Jacobi equation separates and the Riemann curvature tensor satisfies a certain equation (called the diagonal curvature condition). All orthogonal metrics of constant curvature satisfy the diagonal curvature condition. The metrics we find either correspond to a Benenti system or are warped product metrics where the induced metric on the base manifold corresponds to a Benenti system. Furthermore, we show that most metrics we find are characterized by concircular tensors; these metrics, called Kalnins-Eisenhart-Miller metrics, have an intrinsic characterization which can be used to obtain them on a given space. In conjunction with other results, we show that the metrics we found constitute all separable metrics for Riemannian spaces of constant curvature and de Sitter space.
Depositional processes and facies of Trail Fan sandflat: Death Valley, California
Malicse, A.E.; Mazzullo, J.M.; Eide, M.G. (Texas A and M Univ., College Station, TX (United States))
1992-01-01T23:59:59.000Z
A study was conducted of the alluvial fan to playa transition along Trail fan in Death Valley, California with the primary objectives of documenting sedimentary facies and textural features of so-called arid region sandflat. The study involved description of sedimentary structures along trenches and meter-deep cores, description of surficial bedforms, and collection of samples for lithological analyses. Surficial features of Trail Fan sandflat gradually change downdip as a function of texture, ground water depth, and runoff. They include: (1) tongues of mudflows; (2) shallow braided channels that taper out into mudflat or coalesced into single channels; (3) puffy grounds; and (4) flat-smooth surface of the mudflat. The sediment's texture shows a fining downdip trend except when the surface are draped by mudflows. Four facies are distinguished downdip from the alluvial fan to playa mudflat. Facies 1 consists of massive, light gray, matrix to grain supported gravel, and is interpreted as debris flow or streamflow deposit. Facies 2 consists of thin-bedded (0.6--0.06 m), tan, massive, gravelly mud and is interpreted as mudflow deposit. Facies 2 consists of repeated sequences of thick-bedded (0.15 to 0.3 m), massive to planar stratified, graveliferous sand with mud drape and is interpreted as poorly sorted sheetflood or streamflow deposit. Facies 4 consist of light gray, planar laminated, coarsening upward mud to muddy sand, and is interpreted as mudflat facies. This study shows that arid region sandflat facies is a mosaic of mudflow, debris flow, sheetflood and streamflow deposits and is more complex than previous sandflat models described.
Huynh, Long Quang
1994-01-01T23:59:59.000Z
An empirical model has been developed to predict the mean-velocity profile of a turbulent boundary layer under the influence of surface curvature. The model proposed is able to determine the profiles for both a convex and concave curvature...
Huynh, Long Quang
1994-01-01T23:59:59.000Z
An empirical model has been developed to predict the mean-velocity profile of a turbulent boundary layer under the influence of surface curvature. The model proposed is able to determine the profiles for both a convex and concave curvature...
Cerveny, Vlastislav
Relation of the wave{propagation metric tensor to the curvatures of the slowness and ray The contravariant components of the wave{propagation metric tensor equal half the second{order partial derivatives. The relations of the wave{propagation metric tensor to the curvature matrix and Gaussian curvature
Multi Scale Color Coding of Derived Curvature and Torsion Fields on a Multi-Block Curvilinear Grid
Iyengar, S. S.
Multi Scale Color Coding of Derived Curvature and Torsion Fields on a Multi-Block Curvilinear Grid. Abstract: We present a method to compute and visualize the curvature and torsion scalar fields derived from a vector field defined on a multi-block curvilinear grid. In order to compute the curvature and torsion
Paris-Sud XI, Université de
The influence of the curvature dependence of the surface tension on the geometry of electrically, Roio Poggio, I-67040 L'Aquila, Italy We evaluate how the curvature dependence of surface tension of surface tension on curvature becomes important when the "nucle- ation radius" is comparable
Odd scalar curvature in field-antifield formalism
Batalin, Igor A. [Niels Bohr Institute, Blegdamsvej 17, DK-2100 Copenhagen (Denmark); I.E. Tamm Theory Division, P.N. Lebedev Physics Institute, Russian Academy of Sciences, 53 Leninisky Prospect, Moscow 119991 (Russian Federation); Bering, Klaus [Niels Bohr Institute, Blegdamsvej 17, DK-2100 Copenhagen (Denmark); Institute for Theoretical Physics and Astrophysics, Masaryk University, Kotlarska 2, CZ-611 37 Brno (Czech Republic)
2008-03-15T23:59:59.000Z
We consider the possibility of adding a Grassmann-odd function {nu} to the odd Laplacian. Requiring the total {delta} operator to be nilpotent leads to a differential condition for {nu}, which is integrable. It turns out that the odd function {nu} is not an independent geometric object but is instead completely specified by the antisymplectic structure E and the density {rho}. The main impact of introducing the {nu} term is that it makes compatibility relations between E and {rho} obsolete. We give a geometric interpretation of {nu} as (minus (1/8) times) the odd scalar curvature of an arbitrary antisymplectic, torsion-free, and {rho}-compatible connection. We show that the total {delta} operator is a {rho}-dressed version of Khudaverdian's {delta}{sub E} operator, which takes semidensities to semidensities. We also show that the construction generalizes to the situation where {rho} is replaced by a nonflat line bundle connection F. This generalization is implemented by breaking the nilpotency of {delta} with an arbitrary Grassmann-even second-order operator source.
Geometry of matrix product states: Metric, parallel transport, and curvature
Haegeman, Jutho, E-mail: jutho.haegeman@gmail.com; Verstraete, Frank [Vienna Center for Quantum Science and Technology, Faculty of Physics, University of Vienna (Austria) [Vienna Center for Quantum Science and Technology, Faculty of Physics, University of Vienna (Austria); Faculty of Physics and Astronomy, University of Ghent, Krijgslaan 281 S9, 9000 Gent (Belgium); Mariën, Michaël [Faculty of Physics and Astronomy, University of Ghent, Krijgslaan 281 S9, 9000 Gent (Belgium)] [Faculty of Physics and Astronomy, University of Ghent, Krijgslaan 281 S9, 9000 Gent (Belgium); Osborne, Tobias J. [Leibniz Universität Hannover, Institute of Theoretical Physics, Appelstrasse 2, D-30167 Hannover (Germany) [Leibniz Universität Hannover, Institute of Theoretical Physics, Appelstrasse 2, D-30167 Hannover (Germany); Leibniz Universität Hannover, Riemann Center for Geometry and Physics, Appelstrasse 2, D-30167 Hannover (Germany)
2014-02-15T23:59:59.000Z
We study the geometric properties of the manifold of states described as (uniform) matrix product states. Due to the parameter redundancy in the matrix product state representation, matrix product states have the mathematical structure of a (principal) fiber bundle. The total space or bundle space corresponds to the parameter space, i.e., the space of tensors associated to every physical site. The base manifold is embedded in Hilbert space and can be given the structure of a Kähler manifold by inducing the Hilbert space metric. Our main interest is in the states living in the tangent space to the base manifold, which have recently been shown to be interesting in relation to time dependence and elementary excitations. By lifting these tangent vectors to the (tangent space) of the bundle space using a well-chosen prescription (a principal bundle connection), we can define and efficiently compute an inverse metric, and introduce differential geometric concepts such as parallel transport (related to the Levi-Civita connection) and the Riemann curvature tensor.
Primordial black holes from temporally enhanced curvature perturbation
Teruaki Suyama; Yi-Peng Wu; Jun'ichi Yokoyama
2014-06-02T23:59:59.000Z
Scalar field with generalized kinetic interactions metamorphoses depending on its field value, ranging from cosmological constant to stiff matter. We show that such a scalar field can give rise to temporal enhancement of the curvature perturbation in the primordial Universe, leading to efficient production of primordial black holes while the enhancement persists. If the inflation energy scale is high, those mini-black holes evaporate by the Hawking radiation much before Big Bang nucleosynthesis and the effective reheating of the Universe is achieved by the black hole evaporation. Dominance of PBHs and the reheating by their evaporation modify the expansion history of the primordial Universe. This results in a characteristic feature of the spectrum of primordial tensor modes in the DECIGO frequency band, opening an interesting possibility of testing PBH reheating scenario by measuring the primordial tensor modes. If the inflation energy scale is low, the PBH mass can be much larger than the solar mass. In this case, PBH is an interesting candidate for seeds for supermassive black holes residing in present galaxies.
Curvature fluctuations and the Lyapunov exponent at melting
Mehra, V.; Ramaswamy, R. [School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067 (India)] [School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067 (India)
1997-09-01T23:59:59.000Z
We calculate the maximal Lyapunov exponent in constant-energy molecular-dynamics simulations at the melting transition for finite clusters of 6{endash}13 particles (model rare-gas and metallic systems) as well as for bulk rare-gas solids. For clusters, the Lyapunov exponent generally varies linearly with the total energy, but the {ital slope} changes sharply at the melting transition. In the bulk system, melting corresponds to a jump in the Lyapunov exponent, and this corresponds to a singularity in the variance of the curvature of the potential-energy surface. In these systems there are two mechanisms of chaos{emdash}local instability and parametric instability. We calculate the contribution of the parametric instability toward the chaoticity of these systems using a recently proposed formalism. The contribution of parametric instability is a continuous function of energy in small clusters but not in the bulk where the melting corresponds to a decrease in this quantity. This implies that the melting in small clusters does not lead to enhanced local instability. {copyright} {ital 1997} {ital The American Physical Society}
Leading Edge Bacterial Genomics and Pathogen Evolution
Mekalanos, John
Leading Edge Review Bacterial Genomics and Pathogen Evolution David M. Raskin,1 Rekha Seshadri,2 Medical School, Boston, MA 02115, USA 2 The Institute for Genomic Research, 9712 Medical Center Drive.02.002 The availability of hundreds of bacterial genome sequences has altered the study of bacte- rial pathogenesis
PUBLISHED VERSION Edge equilibrium code for tokamaks
and Vladimir V. Drozdov3 1 Institute of Computational Mathematics and Scientific/Engineering Computing, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, P.O. Box 2719, Beijing 100190, China 2 Princeton is developed for simulations of the near edge plasma using the finite element method. It solves the Grad
Holzer, Damon Michael
1997-01-01T23:59:59.000Z
instances. Helgath (1975) was one of the first to cite trail erosion as being more heavily dependent upon physical features such as soil type and geology than use. Likewise, a study of trail erosion in the Great Smoky Mountains National Park found... topographic maps, and polygons were organized into similar LS values. Soil erodibility was processed through information provided in soil survey maps compiled by the Natural Resource Conservation Service (formerly the Soil Conservation Service). A sub...
Curvature perturbation spectra from waterfall transition, black hole constraints and non-Gaussianity
Bugaev, Edgar; Klimai, Peter, E-mail: bugaev@pcbai10.inr.ruhep.ru, E-mail: pklimai@gmail.com [Institute for Nuclear Research, Russian Academy of Sciences, 60th October Anniversary Prospect 7a, 117312 Moscow (Russian Federation)
2011-11-01T23:59:59.000Z
We carried out numerical calculations of a contribution of the waterfall field to the primordial curvature perturbation (on uniform density hypersurfaces) ?, which is produced during waterfall transition in hybrid inflation scenario. The calculation is performed for a broad interval of values of the model parameters. We show that there is a strong growth of amplitudes of the curvature perturbation spectrum in the limit when the bare mass-squared of the waterfall field becomes comparable with the square of Hubble parameter. We show that in this limit the primordial black hole constraints on the curvature perturbations must be taken into account. It is shown that, in the same limit, peak values of the curvature perturbation spectra are far beyond horizon, and the spectra are strongly non-Gaussian.
Taylor, Jean
, in preparation. [ATW1] F. J. Almgren, J. E. Taylor, and L. Wang, A variational approach to motion by weighted. Soc. (1992), 912. [ATW2] F. J. Almgren, J. E. Taylor, and L. Wang, Curvature Driven Flows
All bulk and boundary unitary cubic curvature theories in three dimensions
Guellue, Ibrahim; Sisman, Tahsin Cagri; Tekin, Bayram [Department of Physics, Middle East Technical University, 06531, Ankara (Turkey)
2011-01-15T23:59:59.000Z
We construct all the bulk and boundary unitary cubic curvature parity invariant gravity theories in three dimensions in (anti)-de Sitter spaces. For bulk unitarity, our construction is based on the principle that the free theory of the cubic curvature theory reduces to one of the three known unitary theories which are the cosmological Einstein-Hilbert theory, the quadratic theory of the scalar curvature, or the new massive gravity (NMG). Bulk and boundary unitarity in NMG is in conflict; therefore, cubic theories that are unitary both in the bulk and on the boundary have free theories that reduce to the other two alternatives. We also study the unitarity of the Born-Infeld extensions of NMG to all orders in curvature.
Mean curvature flow self-shrinkers with genus and asymptotically conical ends
Mřller, Niels Martin
2012-01-01T23:59:59.000Z
This doctoral dissertation is on the theory of Minimal Surfaces and of singularities in Mean Curvature Flow, for smooth submanifolds Y" in an ambient Riemannian (n+ 1)-manifold Nn+1, including: (1) New asymptotically conical ...
Dean, J.; Gu, T.; Clyne, T. W.
2014-11-09T23:59:59.000Z
Experimental estimates have been made of typical levels of residual stress in plasma electrolytic oxidation (PEO) coatings formed on aluminium and magnesium alloy substrates. This has been done via measurement of the curvature exhibited by thin...
Kwon, Hyeok-Ran [Department of Biochemistry, College of Medicine, Konyang University, 685 Gasuwon-dong, Seo-gu, Daejeon 302-718 (Korea, Republic of)] [Department of Biochemistry, College of Medicine, Konyang University, 685 Gasuwon-dong, Seo-gu, Daejeon 302-718 (Korea, Republic of); Lee, Ki Won [Department of Bioscience and Biotechnology, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701 (Korea, Republic of)] [Department of Bioscience and Biotechnology, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701 (Korea, Republic of); Dong, Zigang [Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912 (United States)] [Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912 (United States); Lee, Kyung Bok [Department of Biochemistry, College of Medicine, Konyang University, 685 Gasuwon-dong, Seo-gu, Daejeon 302-718 (Korea, Republic of)] [Department of Biochemistry, College of Medicine, Konyang University, 685 Gasuwon-dong, Seo-gu, Daejeon 302-718 (Korea, Republic of); Oh, Sang-Muk, E-mail: sangmuk_oh@konyang.ac.kr [Department of Biochemistry, College of Medicine, Konyang University, 685 Gasuwon-dong, Seo-gu, Daejeon 302-718 (Korea, Republic of)] [Department of Biochemistry, College of Medicine, Konyang University, 685 Gasuwon-dong, Seo-gu, Daejeon 302-718 (Korea, Republic of)
2010-01-01T23:59:59.000Z
T-lymphokine-activated killer cell-originated protein kinase (TOPK) appears to be highly expressed in various cancer cells and to play an important role in maintaining proliferation of cancer cells. However, the underlying mechanism by which TOPK regulates growth of cancer cells remains elusive. Here we report that upregulated endogenous TOPK augments resistance of cancer cells to apoptosis induced by tumor necrosis factor-related apoptosis inducing ligand (TRAIL). Stable knocking down of TOPK markedly increased TRAIL-mediated apoptosis of human HeLa cervical cancer cells, as compared with control cells. Caspase 8 or caspase 3 activities in response to TRAIL were greatly incremented in TOPK-depleted cells. Ablation of TOPK negatively regulated TRAIL-mediated NF-{kappa}B activity. Furthermore, expression of NF-{kappa}B-dependent genes, FLICE-inhibitory protein (FLIP), inhibitor of apoptosis protein 1 (c-IAP1), or X-linked inhibitor of apoptosis protein (XIAP) was reduced in TOPK-depleted cells. Collectively, these findings demonstrated that TOPK contributed to TRAIL resistance of cancer cells via NF-{kappa}B activity, suggesting that TOPK might be a potential molecular target for successful cancer therapy using TRAIL.
Peter Kuchment; Andrew Raich
2011-10-02T23:59:59.000Z
Precise asymptotics known for the Green's function of the Laplace operator have found their analogs for periodic elliptic operators of the second order at and below the bottom of the spectrum. Due to the band-gap structure of the spectra of such operators, the question arises whether similar results can be obtained near or at the edges of spectral gaps. As the result of this work shows, this is possible at a spectral edge in dimensions d>2.
Space-time curvature due to quantum vacuum fluctuations: An alternative to dark energy?
Santos, Emilio
2010-01-01T23:59:59.000Z
It is pointed out that quantum vacuum fluctuations may give rise to a curvature of space-time equivalent to the curvature currently attributed to dark energy. A simple calculation is made, which suggests that the value of the dark energy density is roughly given by the product of Newton constant time the quantity m^6 c^4 h^-4, m being a typical mass of elementary particles. The estimate is compatible with observations.
Space-time curvature due to quantum vacuum fluctuations: An alternative to dark energy?
Emilio Santos
2009-12-30T23:59:59.000Z
It is pointed out that quantum vacuum fluctuations may give rise to a curvature of space-time equivalent to the curvature currently attributed to dark energy. A simple calculation is made, which suggests that the value of the dark energy density is roughly given by the product of Newton constant time the quantity m^6 c^4 h^-4, m being a typical mass of elementary particles. The estimate is compatible with observations.
Tracking Objects Using 3D Edge Detectors February 2013
O'Leary, Dianne P.
Tracking Objects Using 3D Edge Detectors February 2013 SIAM CSE 2013 Dianne P. O'Leary c 2013 1 #12;Tracking Objects Using 3D Edge Detectors Dianne P. O'Leary Computer Science Dept. and Institute
Method for encapsulating the edge of a flexible sheet
Keenihan, James R; Clarey, Todd M
2013-02-19T23:59:59.000Z
The present invention is premised upon an inventive method of producing an over-molded edge portion on a flexible substrate, wherein the edge portion is void of open areas due to support devices in the mold cavity.
Edge Direction and the Structure of Networks
Foster, Jacob G; Grassberger, Peter; Paczuski, Maya
2009-01-01T23:59:59.000Z
Directed networks are ubiquitous, from food webs to the World Wide Web, but the directionality of their interactions has been disregarded in most studies of global network structure. One important global property is the tendency of nodes with similar numbers of edges to be connected. This tendency, called assortativity, affects crucial structural and dynamic properties of real-world networks. Here we demonstrate the importance of edge direction by studying assortativity in directed networks. We define a set of four directed assortativity measures. By comparison to randomized networks, we discover significant features of three network classes: online/social networks, food webs, and word-adjacency networks. The full set of measures is needed to reveal patterns common to the class or to separate networks that have been previously classified together. Our measures expose limitations of existing theoretical models, and show that many networks are not purely assortative or disassortative but a mixture of the two.
Imaging topological edge states in silicon photonics
M. Hafezi; S. Mittal; J. Fan; A. Migdall; J. Taylor
2015-04-03T23:59:59.000Z
Topological features - global properties not discernible locally - emerge in systems from liquid crystals to magnets to fractional quantum Hall systems. Deeper understanding of the role of topology in physics has led to a new class of matter: topologically - ordered systems. The best known examples are quantum Hall effects, where insensitivity to local properties manifests itself as conductance through edge states that is insensitive to defects and disorder. Current research in engineering topological order primarily focuses on analogies to quantum Hall systems, where the required magnetic field is synthesized in non-magnetic systems. Here, we realize synthetic magnetic fields for photons at room temperature, using linear Silicon photonics. We observe, for the first time, topological edge states of light in a two - dimensional system and show their robustness against intrinsic and introduced disorder. Our experiment demonstrates the feasibility of using photonics to realize topological order in both the non-interacting and many-body regimes.
Ames, Forrest; Bons, Jeffrey
2014-09-30T23:59:59.000Z
The Department of Energy has goals to move land based gas turbine systems to alternate fuels including coal derived synthetic gas and hydrogen. Coal is the most abundant energy resource in the US and in the world and it is economically advantageous to develop power systems which can use coal. Integrated gasification combined cycles are (IGCC) expected to allow the clean use of coal derived fuels while improving the ability to capture and sequester carbon dioxide. These cycles will need to maintain or increase turbine entry temperatures to develop competitive efficiencies. The use of coal derived syngas introduces a range of potential contaminants into the hot section of the gas turbine including sulfur, iron, calcium, and various alkali metals. Depending on the effectiveness of the gas clean up processes, there exists significant likelihood that the remaining materials will become molten in the combustion process and potentially deposit on downstream turbine surfaces. Past evidence suggests that deposition will be a strong function of increasing temperature. Currently, even with the best gas cleanup processes a small level of particulate matter in the syngas is expected. Consequently, particulate deposition is expected to be an important consideration in the design of turbine components. The leading edge region of first stage vanes most often have higher deposition rates than other areas due to strong fluid acceleration and streamline curvature in the vicinity of the surface. This region remains one of the most difficult areas in a turbine nozzle to cool due to high inlet temperatures and only a small pressure ratio for cooling. The leading edge of a vane often has relatively high heat transfer coefficients and is often cooled using showerhead film cooling arrays. The throat of the first stage nozzle is another area where deposition potentially has a strongly adverse effect on turbine performance as this region meters the turbine inlet flow. Based on roughness levels found on in service vanes (Bons, et al., 2001, up to 300 microns) flow blockage in first stage turbine nozzles can easily reach 1 to 2 percent in conventional turbines. Deposition levels in syngas fueled gas turbines are expected to be even more problematic. The likelihood of significant deposition to the leading edge of vanes in a syngas environment indicates the need to examine this effect on the leading edge cooling problem. It is critical to understand the influence of leading edge geometry and turbulence on deposition rates for both internally and showerhead cooled leading edge regions. The expected level of deposition in a vane stagnation region not only significantly changes the heat transfer problem but also suggests that cooling arrays may clog. Addressing the cooling issue suggests a need to better understand stagnation region heat transfer with realistic roughness as well as the other variables affecting transport near the leading edge. Also, the question of whether leading edge regions can be cooled internally with modern cooling approaches should also be raised, thus avoiding the clogging issue. Addressing deposition in the pressure side throat region of the nozzle is another critical issue for this environment. Issues such as examining the protective effect of slot and full coverage discrete-hole film cooling on limiting deposition as well as the influence of roughness and turbulence on effectiveness should be raised. The objective of this present study is to address these technical challenges to help enable the development of high efficiency syngas tolerant gas turbine engines.
Rimmed and edge thickened Stodola shaped flywheel
Kulkarni, S.V.; Stone, R.G.
1983-10-11T23:59:59.000Z
A flywheel is described that is useful for energy storage in a hybrid vehicle automotive power system or in some stationary applications. The flywheel has a body composed of essentially planar isotropic high strength material. The flywheel body is enclosed by a rim of circumferentially wound fiber embedded in resin. The rim promotes flywheel safety and survivability. The flywheel has a truncated and edge thickened Stodola shape designed to optimize system mass and energy storage capability. 6 figs.
Permanent magnet edge-field quadrupole
Tatchyn, Roman O. (Mountain View, CA)
1997-01-01T23:59:59.000Z
Planar permanent magnet edge-field quadrupoles for use in particle accelerating machines and in insertion devices designed to generate spontaneous or coherent radiation from moving charged particles are disclosed. The invention comprises four magnetized rectangular pieces of permanent magnet material with substantially similar dimensions arranged into two planar arrays situated to generate a field with a substantially dominant quadrupole component in regions close to the device axis.
Application of Quantitative Fluorescence and Absorption-Edge
Sparks, Donald L.
Application of Quantitative Fluorescence and Absorption-Edge Computed Microtomography to Image, Chicago, Illinois 60637 This paper shows that synchrotron-based fluorescence and absorption-edge computed, which had a well-correlated metal coating. Absorption-edge CMT showed the three-dimensional distribution
Dislocations With Edge Components in Nanocrystalline bcc Mo
G. M. Cheng; W. Z. Xu; W. W. Jian; H. Yuan; M. H. Tsai; Y. T. Zhu; Y. F. Zhang; Paul C. Millett
2013-07-01T23:59:59.000Z
We report high-resolution transmission electron microscopy (HRTEM) observation of a high density of dislocations with edge components (approximately 1016 m-2) in nanocrystalline (NC) body-centered cubic (bcc) Mo prepared by high-pressure torsion. We also observed for the first time of the 1/2 <111> and <001> pure edge dislocations in NC Mo. Crystallographic analysis and image simulations reveal that the best way using HRTEM to study dislocations with edge components in bcc systems is to take images along <110> zone axis, from which it is possible to identify 1/2 <111> pure edge dislocations, and edge components of 1/2 <111> and <001> mixed dislocations. The <001> pure edge dislocations can only be identified from <100> zone axis. The high density of dislocations with edge components is believed to play a major role in the reduction of strain rate sensitivity in NC bcc metals and alloys.
K-edge densitometer (KED). User manual
Sprinkle, J.K.; Hansen, W.J.
1993-02-11T23:59:59.000Z
In 1979, a K-edge densitometer (KED) was installed by the Safeguards Assay group from Los Alamos National Laboratory in the PNC reprocessing plant at Tokai-mura, Japan. It uses an active nondestructive assay technique, KED, to measure the plutonium concentration of the product solution. The measurement uncertainty of an assay depends on the count time chosen, but can be 0.5% or better. The computer hardware and software were upgraded in 1992. This manual describes the operation of the instrument, with an emphasis on the user interface to the software.
Rimmed and edge thickened Stodola shaped flywheel
Kulkarni, Satish V. (San Ramon, CA); Stone, Richard G. (Oakland, CA)
1983-01-01T23:59:59.000Z
A flywheel (10) is described that is useful for energy storage in a hybrid vehicle automotive power system or in some stationary applications. The flywheel (10) has a body (15) composed of essentially planar isotropic high strength material. The flywheel (10) body (15) is enclosed by a rim (50) of circumferentially wound fiber (2) embedded in resin (3). The rim (50) promotes flywheel (10) safety and survivability. The flywheel (10) has a truncated and edge thickened Stodola shape designed to optimize system mass and energy storage capability.
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Microchannel Cooled Edge Cladding to Establish an Adiabatic Boundary Condition in a Slab Laser
Albrecht, Georg F.; Beach, Raymond J.; Solarz, Richard W.
2004-05-18T23:59:59.000Z
The present invention provides an edge cladding for a slab laser, the edge cladding comprising a cooling channel system therein.
Curvature conditions for the occurrence of a class of spacetime singularities
W. Rudnicki; P. Zieba
1999-04-15T23:59:59.000Z
It has previously been shown [W. Rudnicki, Phys. Lett. A 224, 45 (1996)] that a generic gravitational collapse cannot result in a naked singularity accompanied by closed timelike curves. An important role in this result plays the so-called inextendibility condition, which is required to hold for certain incomplete null geodesics. In this paper, a theorem is proved that establishes some relations between the inextendibility condition and the rate of growth of the Ricci curvature along incomplete null geodesics. This theorem shows that the inextendibility condition may hold for a much more general class of singularities than only those of the strong curvature type. It is also argued that some earlier cosmic censorship results obtained for strong curvature singularities can be extended to singularities corresponding to the inextendibility condition.
The Influence of Graphene Curvature on Hydrogen Adsorption: Towards Hydrogen Storage Devices
Goler, Sarah; Tozzini, Valentina; Piazza, Vincenzo; Mashoff, Torge; Beltram, Fabio; Pellegrini, Vittorio; Heun, Stefan
2013-01-01T23:59:59.000Z
The ability of atomic hydrogen to chemisorb on graphene makes the latter a promising material for hydrogen storage. Based on scanning tunneling microscopy techniques, we report on site-selective adsorption of atomic hydrogen on convexly curved regions of monolayer graphene grown on SiC(0001). This system exhibits an intrinsic curvature owing to the interaction with the substrate. We show that at low coverage hydrogen is found on convex areas of the graphene lattice. No hydrogen is detected on concave regions. These findings are in agreement with theoretical models which suggest that both binding energy and adsorption barrier can be tuned by controlling the local curvature of the graphene lattice. This curvature-dependence combined with the known graphene flexibility may be exploited for storage and controlled release of hydrogen at room temperature making it a valuable candidate for the implementation of hydrogen-storage devices.
Curvature and folding dynamo effects in turbulent plasmas and ABC flux tubes
de Andrade, L C Garcia
2010-01-01T23:59:59.000Z
Investigation of the eigenvalue spectra of dynamo solutions, has been proved fundamental for the knowledge of dynamo physics. Earlier, curvature-folding relation on dynamos in Riemannian spaces has been investigated [PPL 2008]. Here, analytical solutions representing general turbulent dynamo filaments are obtained in resistive plasmas. Turbulent diffusivity with vanishing kinetic helicity yields a fast mode for a steady dynamo eigenvalue. The magnetic field lays down on a local frame 2 plane along the filaments embedded in a 3D plasma. Curvature effects plays the role of folding in fast magnetic dynamos. In the present examples, plasma equipartition between normal and binormal components of the magnetic field components is considered. In the opposite case, oscillatory, purely imaginary, branches of the spectrum are found in dynamo manifold. Degenerate eigenvalues, are obtained when the dynamo growth rate coincides with the filaments curvature. Spectra of dynamo obtained are similar to the fast dynamo solution...
Okuyama, Naoya [Department of Physics, Waseda University, Okubo 3-4-1, Shinjuku, Tokyo 169-8555 (Japan); Koga, Jun-ichirou [Advanced Research Institute for Science and Engineering, Waseda University, Okubo 3-4-1, Shinjuku, Tokyo 169-8555 (Japan)
2005-04-15T23:59:59.000Z
We consider n-dimensional asymptotically anti-de Sitter spacetimes in higher curvature gravitational theories with n{>=}4, by employing the conformal completion technique. We first argue that a condition on the Ricci tensor should be supplemented to define an asymptotically anti-de Sitter spacetime in higher curvature gravitational theories and propose an alternative definition of an asymptotically anti-de Sitter spacetime. Based on that definition, we then derive a conservation law of the gravitational field and construct conserved quantities in two classes of higher curvature gravitational theories. We also show that these conserved quantities satisfy a balance equation in the same sense as in Einstein gravity and that they reproduce the results derived elsewhere. These conserved quantities are shown to be expressed as an integral of the electric part of the Weyl tensor alone and hence they vanish identically in the pure anti-de Sitter spacetime as in the case of Einstein gravity.
More on the Asymmetric Infinite Square Well: Energy Eigenstates with Zero Curvature
L. P. Gilbert; M. Belloni; M. A. Doncheski; R. W. Robinett
2005-12-19T23:59:59.000Z
We extend the standard treatment of the asymmetric infinite square well to include solutions that have zero curvature over part of the well. This type of solution, both within the specific context of the asymmetric infinite square well and within the broader context of bound states of arbitrary piecewise-constant potential energy functions, is not often discussed as part of quantum mechanics texts at any level. We begin by outlining the general mathematical condition in one-dimensional time-independent quantum mechanics for a bound-state wave function to have zero curvature over an extended region of space and still be a valid wave function. We then briefly review the standard asymmetric infinite square well solutions, focusing on zero-curvature solutions as represented by energy eigenstates in position and momentum space.
Curvature Induced Activation of a Passive Tracer in an Active Bath
S. A. Mallory; C. Valeriani; A. Cacciuto
2014-09-25T23:59:59.000Z
We use numerical simulations to study the motion of a large asymmetric tracer immersed in a low density suspension of self-propelled nanoparticles in two dimensions. Specifically, we analyze how the curvature of the tracer affects its translational and rotational motion in an active environment. We find that even very small amounts of curvature are sufficient for the active bath to impart directed motion to the tracer which results in its effective activation. We propose simple scaling arguments to characterize this induced activity in terms of the curvature of the tracer and the strength of the self-propelling force. Our results suggest new ways of controlling the transport properties of passive tracers in an active medium by carefully tailoring their geometry.
Edge Transport Barrier Studies On the Alcator C-Mod Tokamak
Hughes, Jerry
tokamak edge transport barrier (ETB) · ETB diagnosis on C-Mod with edge Thomson scattering · Edge phase tokamak edge transport barrier (ETB) · ETB diagnosis on C-Mod with edge Thomson scattering · Edge phase · Conclusions #12;J.W. Hughes, Ph.D. Defense. July 5, 2005. Slide 4 ETBs on tokamaks · Localized reduction
Edge Transport in 2D Cold Atom Optical Lattices
V. W. Scarola; S. Das Sarma
2007-05-24T23:59:59.000Z
We theoretically study the observable response of edge currents in two dimensional cold atom optical lattices. As an example we use Gutzwiller mean-field theory to relate persistent edge currents surrounding a Mott insulator in a slowly rotating trapped Bose-Hubbard system to time of flight measurements. We briefly discuss an application, the detection of Chern number using edge currents of a topologically ordered optical lattice insulator.
Electron spin magnetism of zigzag graphene nanoribbon edge states
Xu, Kun, E-mail: xu83@purdue.edu; Ye, Peide D. [School of Electrical and Computer Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States)
2014-04-21T23:59:59.000Z
The electron spin states of zigzag graphene nanoribbon (ZGNR) edge play a pivotal role in the applications of graphene nanoribbons. However, the exact arrangements of the electron spins remain unclear to date. In this report, the electronic spin states of the ZGNR edge have been elucidated through a combination of quantum chemical investigation and previous electron spin resonance experiment observations. An alternating ? and ? spin configuration of the unpaired electrons along the ZGNR edge is established in ambient condition without any external magnetic field, and the origin of the spin magnetism of the ZGNR edge is revealed. It paves a pathway for the understanding and design of graphene based electronic and spintronic devices.
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Transcript, Keeping the Edge: Enhancing Performance by Managing Culture
Broader source: Energy.gov [DOE]
Transcript: 2003 INPO CEO Conference, Keeping the Edge: “Enhancing Performance by Managing Culture” Edgar H. Schein, Ph.D. Professor Emeritis, Massachusetts Institute of Technology November 7, 2003
Edge Turbulence Velocity Changes with Lithium Coating on NSTX
Cao, A.; Zweben, S. J.; Stotler, D. P.; Bell, M.; Diallo, A.; Kaye, S. M.; LeBlanc, B.
2012-08-10T23:59:59.000Z
Lithium coating improves energy confinement and eliminates edge localized modes in NSTX, but the mechanism of this improvement is not yet well understood. We used the gas-puff-imaging (GPI) diagnostic on NSTX to measure the changes in edge turbulence which occurred during a scan with variable lithium wall coating, in order to help understand the reason for the confinement improvement with lithium. There was a small increase in the edge turbulence poloidal velocity and a decrease in the poloidal velocity fluctuation level with increased lithium. The possible effect of varying edge neutral density on turbulence damping was evaluated for these cases in NSTX. __________________________________________________
Characterizing the geometrical edges of nonlocal two-qubit gates
S. Balakrishnan; R. Sankaranarayanan
2009-05-30T23:59:59.000Z
Nonlocal two-qubit gates are geometrically represented by tetrahedron known as Weyl chamber within which perfect entanglers form a polyhedron. We identify that all edges of the Weyl chamber and polyhedron are formed by single parametric gates. Nonlocal attributes of these edges are characterized using entangling power and local invariants. In particular, SWAP (power)alpha family of gates constitutes one edge of the Weyl chamber with SWAP-1/2 being the only perfect entangler. Finally, optimal constructions of controlled-NOT using SWAP-1/2 gate and gates belong to three edges of the polyhedron are presented.
Dainty, Chris
Received July 26, 2000 A new wave-front sensor for adaptive optics that gives signals for the curvatureDecember 1, 2000 / Vol. 25, No. 23 / OPTICS LETTERS 1687 Hybrid curvature and gradient wave-front sensor C. Paterson and J. C. Dainty The Blackett Laboratory, Imperial College, London, SW7 2BZ, UK
The formation of mountain range curvature by gravitational spreading Alex Copley
of the geological record of mountain building (e.g. Platt et al., 1989; Hindle and Burkhard, 1999). A variety in the development of mountain range curvature (e.g. Merle, 1989; Platt et al., 1989), and the main aim of this paper
Experimental Study of Curvature-based Control Laws for Obstacle Avoidance
Zhang, Fumin
, krishna}@isr.umd.edu Abstract-- A novel curvature-based steering control law is introduced to produce- thermore, with appropriate dynamic model, the algorithm produces an explicit control law for the robot, a recent development in this category is to keep the robot moving at a constant speed with steering control
Evaluation of Viewport Size and Curvature of Large, High-Resolution Displays
of geospatial tasks that may be used in aerial im- agery comparison and analysis. Geospatial data is ideal compared user performance time, accu- racy, and mental workload on geospatial search, route tracing- figurable display, viewport size, curvature, geospatial 1 Introduction Tiling multiple monitors to increase
Evaluation of Viewport Size and Curvature of Large, High-Resolution Displays
Ball, Robert
of geospatial tasks that may be used in aerial imagery compari- son and analysis. One of the reasons for using in better user performance. We compared user perfor- mance time, accuracy, and mental workload on geospatial, viewport size, curvature, geospatial ACM Classification Keywords H.5.2 [User Interfaces] Ergonomics
Wightman function and the Casimir effect for a Robin sphere in a constant curvature space
S. Bellucci; A. A. Saharian; N. A. Saharyan
2014-07-03T23:59:59.000Z
We evaluate the Wightman function, the mean field squared and the vacuum expectation value (VEV) of the energy-momentum tensor for a scalar field with Robin boundary condition on a spherical shell in the background of a constant negative curvature space. For the coefficient in the boundary condition there is a critical value above which the scalar vacuum becomes unstable. In both interior and exterior regions, the VEVs are decomposed into the boundary-free and sphere-induced contributions. For the latter, rapidly convergent integral representations are provided. In the region inside the sphere, the eigenvalues are expressed in terms of the zeros of the combination of the associated Legendre function and its derivative and the decomposition is achieved by making use of the Abel-Plana type summation formula for the series over these zeros. The sphere-induced contribution to the VEV of the field squared is negative for Dirichlet boundary condition and positive for Neumann one. At distances from the sphere larger than the curvature scale of the background space the suppression of the vacuum fluctuations in the gravitational field corresponding to the negative curvature space is stronger compared with the case of the Minkowskian bulk. In particular, the decay of the VEVs with the distance is exponential for both massive and massless fields. The corresponding results are generalized for spaces with spherical bubbles and for cosmological models with negative curvature spaces.
Heat transfer in soft nanoscale interfaces: the influence of interface curvature
Kjelstrup, Signe
Heat transfer in soft nanoscale interfaces: the influence of interface curvature Anders Lervik transient non-equilibrium molecular-dynamics simulations, heat-transfer through nanometer-scale interfaces processes. We show that the modeling of heat transfer across a nanodroplet/fluid interface requires
Integrability of the sub-Riemannian mean curvature of surfaces in ...
D. Danielli; N. Garofalo; D. M. Nhieu
2011-11-16T23:59:59.000Z
Nov 2, 2011 ... 1. Introduction. The local summability of the sub-Riemannian mean curvature H of a hypersur- ... 1. 2. (xy ? x y)). A basis for the Lie algebra of left-invariant vector fields on H1 associated with ...... MR2021034 (2005d:43007).
Lyapunov spectra in fast dynamo Ricci flows of negative sectional curvature
Garcia de Andrade
2008-11-25T23:59:59.000Z
Previously Chicone, Latushkin and Montgomery-Smith [\\textbf{Comm. Math. Phys. \\textbf{173},(1995)}] have investigated the spectrum of the dynamo operator for an ideally conducting fluid. More recently, Tang and Boozer [{\\textbf{Phys. Plasmas (2000)}}], have investigated the anisotropies in magnetic field dynamo evolution, from finite-time, Lyapunov exponents, giving rise to a Riemann metric tensor, in the Alfven twist in magnetic flux tubes (MFTs). In this paper one investigate the role of Perelman Ricci flows constraints in twisted magnetic flux tubes, where the Lyapunov eigenvalue spectra for the Ricci tensor associated with the Ricci flow equation in MFTs leads to a finite-time Lyapunov exponential stretching along the toroidal direction of the tube and a contraction along the radial direction of the tube. It is shown that in the case of MFTs, the sectional Ricci curvature of the flow, is negative as happens in geodesic flows of Anosov type. Ricci flows constraints in MFTs substitute the Thiffeault and Boozer [\\textbf{Chaos}(2001)] have vanishing of Riemann curvature constraint on the Lyapunov exponential stretching of chaotic flows. Gauss curvature of the twisted MFT is also computed and the contraints on a negative Gauss curvature are obtained.
Application of the 3D Edge Code EMC3-EIRENE to JET Single Null Configurations by Validating Against 2D Simulations with EDGE2D-EIRENE
Enhanced Half-Metallicity in Edge-Oxidized Zigzag Graphene
Hod, Oded
Enhanced Half-Metallicity in Edge-Oxidized Zigzag Graphene Nanoribbons Oded Hod,* Vero´nica Barone theoretical study of the electronic properties and relative stabilities of edge-oxidized zigzag graphene with nanometer scale dimen- sions. Recently, a new type of graphene-based material was experimentally realized.12
Inference of Edge Replacement Graph Grammars Jacek P. Kukluk1
Holder, Lawrence B.
Inference of Edge Replacement Graph Grammars Jacek P. Kukluk1 , Lawrence B. Holder2 , and Diane J@eecs.wsu.edu Abstract We describe an algorithm and experiments for inference of edge replacement graph grammars for inference of Node Replacement Recursive Graph Grammars [7]. In this paper we describe an approach
absorption edge spectroscopy: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
absorption edge spectroscopy First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Communications: Near edge...
absorption edge detector: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
absorption edge detector First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 A combined corner and edge...
absorption edge imaging: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
absorption edge imaging First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Denoising and edge detection...
1 How (Not) to Protect Genomic Data Privacy in a Distributed Network: Using Trail Re-specific genomic data into clinical practice and research raises serious privacy concerns. Various systems have being disclosed, they lack formal proofs. In this paper, we study the erosion of privacy when genomic
Edge profile measurements using Thomson scattering on the KSTAR tokamak
Lee, J. H., E-mail: jhleel@nfri.re.kr; Ko, W. H. [National Fusion Research Institute, Daejeon (Korea, Republic of); Department of Nuclear Fusion and Plasma Science, University of Science and Technology (UST), Daejeon (Korea, Republic of); Oh, S.; Lee, W. R.; Kim, K. P.; Lee, K. D.; Jeon, Y. M.; Yoon, S. W.; Cho, K. W. [National Fusion Research Institute, Daejeon (Korea, Republic of); Narihara, K.; Yamada, I.; Yasuhara, R. [National Institute for Fusion Science, Nagoya (Japan); Hatae, T.; Yatsuka, E.; Ono, T. [Japan Atomic Energy Agency, Naka (Japan); Hong, J. H. [Department of Physics, KAIST (Korea, Republic of)
2014-11-15T23:59:59.000Z
In the KSTAR Tokamak, a “Tangential Thomson Scattering” (TTS) diagnostic system has been designed and installed to measure electron density and temperature profiles. In the edge system, TTS has 12 optical fiber bundles to measure the edge profiles with 10–15 mm spatial resolution. These 12 optical fibers and their spatial resolution are not enough to measure the pedestal width with a high accuracy but allow observations of L-H transition or H-L transitions at the edge. For these measurements, the prototype ITER edge Thomson Nd:YAG laser system manufactured by JAEA in Japan is installed. In this paper, the KSTAR TTS system is briefly described and some TTS edge profiles are presented and compared against the KSTAR Charge Exchange Spectroscopy and other diagnostics. The future upgrade plan of the system is also discussed in this paper.
Kuiper, James A; Krummel, John R; Hlava, Kevin J; Moore, H Robert; Orr, Andrew B; Schlueter, Scott O; Sullivan, Robert G; Zvolanek, Emily A
2014-03-25T23:59:59.000Z
As has been noted in many reports and publications, acquiring new or expanded rights-of-way for transmission is a challenging process, because numerous land use and land ownership constraints must be overcome to develop pathways suitable for energy transmission infrastructure. In the eastern U.S., more than twenty federally protected national trails (some of which are thousands of miles long, and cross many states) pose a potential obstacle to the development of new or expanded electricity transmission capacity. However, the scope of this potential problem is not well-documented, and there is no baseline information available that could allow all stakeholders to study routing scenarios that could mitigate impacts on national trails. This report, Electricity Transmission, Pipelines, and National Trails: An Analysis of Current and Potential Intersections on Federal Lands in the Eastern United States, was prepared by the Environmental Science Division of Argonne National Laboratory (Argonne). Argonne was tasked by DOE to analyze the “footprint” of the current network of National Historic and Scenic Trails and the electricity transmission system in the 37 eastern contiguous states, Alaska, and Hawaii; assess the extent to which national trails are affected by electrical transmission; and investigate the extent to which national trails and other sensitive land use types may be affected in the near future by planned transmission lines. Pipelines are secondary to transmission lines for analysis, but are also within the analysis scope in connection with the overall directives of Section 368 of the Energy Policy Act of 2005, and because of the potential for electrical transmission lines being collocated with pipelines. Based on Platts electrical transmission line data, a total of 101 existing intersections with national trails on federal land were found, and 20 proposed intersections. Transmission lines and pipelines are proposed in Alaska; however there are no locations that intersect national trails. Source data did not indicate any planned transmission lines or pipelines in Hawaii. A map atlas provides more detailed mapping of the topics investigated in this study, and the accompanying GIS database provides the baseline information for further investigating locations of interest. In many cases the locations of proposed transmission lines are not accurately mapped (or a specific route may not yet be determined), and accordingly the specific crossing locations are speculative. However since both national trails and electrical transmission lines are long linear systems, the characteristics of the crossings reported in this study are expected to be similar to both observed characteristics of the existing infrastructure provided in this report, and of the new infrastructure if these proposed projects are built. More focused study of these siting challenges is expected to mitigate some of potential impacts by choosing routes that minimize or eliminate them. The current study primarily addresses a set of screening-level characterizations that provide insights into how the National Trail System may influence the siting of energy transport facilities in the states identified under Section 368(b) of the Energy Policy Act of 2005. As such, it initializes gathering and beginning analysis of the primary environmental and energy data, and maps the contextual relationships between an important national environmental asset and how this asset intersects with energy planning activities. Thus the current study sets the stage for more in-depth analyses and data development activities that begin to solve key transmission siting constraints. Our recommendations for future work incorporate two major areas: (1) database development and analytics and (2) modeling and scenario analysis for energy planning. These recommendations provide a path forward to address key issues originally developed under the Energy Policy Act of 2005 that are now being carried forward under the President’s Climate Action Plan.
Edge-localized-modes in tokamaks
Leonard, A. W. [General Atomics, PO Box 85608, San Diego, California 92186-5608 (United States)
2014-09-15T23:59:59.000Z
Edge-localized-modes (ELMs) are a ubiquitous feature of H-mode in tokamaks. When gradients in the H-mode transport barrier grow to exceed the MHD stability limit the ELM instability grows explosively, rapidly transporting energy and particles onto open field lines and material surfaces. Though ELMs provide additional particle and impurity transport through the H-mode transport barrier, enabling steady operation, the resulting heat flux transients to plasma facing surfaces project to large amplitude in future low collisionality burning plasma tokamaks. Measurements of the ELM heat flux deposition onto material surfaces in the divertor and main chamber indicate significant broadening compared to inter-ELM heat flux, with a timescale for energy deposition that is consistent with sonic ion flow and numerical simulation. Comprehensive ELM simulation is highlighting the important physics processes of ELM transport including parallel transport due to magnetic reconnection and turbulence resulting from collapse of the H-mode transport barrier. Encouraging prospects for ELM control and/or suppression in future tokamaks include intrinsic modes of ELM free operation, ELM triggering with frequent small pellet injection and the application of 3D magnetic fields.
CMS kinematic edge from s-bottoms
Peisi Huang; Carlos E. M. Wagner
2015-02-05T23:59:59.000Z
We present two scenarios in the Minimal Supersymmetric Extension of the Standard Model (MSSM) that can lead to an explanation of the excess in the invariant mass distribution of two opposite charged, same flavor leptons, and the corresponding edge at an energy of about 78 GeV, recently reported by the CMS collaboration. In both scenarios, s-bottoms are pair produced, and decay to neutralinos and a b-jet. The heavier neutralinos further decay to a pair of leptons and the lightest neutralino through on-shell s-leptons or off-shell neutral gauge bosons. These scenarios are consistent with the current limits on the s-bottoms, neutralinos, and s-leptons. Assuming that the lightest neutralino is stable we discuss the predicted relic density as well as the implications for Dark Matter direct detection. We show that consistency between the predicted and the measured value of the muon anomalous magnetic moment may be obtained in both scenarios. Finally, we define the signatures of these models that may be tested at the 13 TeV run of the LHC.
Minfer: Inferring Motif Statistics From Sampled Edges
Wang, Pinghui; Towsley, Don
2015-01-01T23:59:59.000Z
Characterizing motif (i.e., locally connected subgraph patterns) statistics is important for understanding complex networks such as online social networks and communication networks. Previous work made the strong assumption that the graph topology of interest is known, and that the dataset either fits into main memory or stored on disks such that it is not expensive to obtain all neighbors of any given node. In practice, researchers have to deal with the situation where the graph topology is unknown, either because the graph is dynamic, or because it is expensive to collect and store all topological and meta information on disk. Hence, what is available to researchers is only a snapshot of the graph generated by sampling edges from the graph at random, which we called a "RESampled graph". Clearly, a RESampled graph's motif statistics may be quite different from the underlying original graph. To solve this challenge, we propose a framework and implement a system called Minfer, which can take the given RESample...
Chemistry on the Edge: A Microscopic Analysis of the Intercalation, Exfoliation, EdgeVed May 29, 1998 Abstract: The intercalation and exfoliation reactions of R-zirconium phosphate, Zr(HPO4-assembled aperiodic multilayers.3 The exfoliation of clays, alkali transition metal oxides, metal phosphates, graphite
Hughes, Jerry
are associated with edge transport barrier (ETB) formation in tokamaks, are investigated on Alcator C little effect on density gradient scale lengths in the ETB and a relatively weak impact on the height-mode) regime [3] is the result of a strong edge transport barrier (ETB), evinced by localized regions
On the edge-connectivity of Cartesian product graphs Sandi Klavzar
Klavzar, Sandi
, then either S is induced by a minimum edge cut of a factor, or S is a set of edges incident to a vertex of G H is given and the structure of minimum edge cuts is described. It is also proved that the connectivity product of graphs; edge-connectivity; minimum edge cuts; AMS subject classification (2000): 05C40 1
A Model of Curvature-Induced Phase Transitions in Inflationary Universe
J. Hashida; S. Mukaigawa; T. Muta; K. Ohkura; K. Yamamoto
1998-12-21T23:59:59.000Z
Chiral phase transitions driven by space-time curvature effects are investigated in de Sitter space in the supersymmetric Nambu-Jona-Lasinio model with soft supersymmetry breaking. The model is considered to be suitable for the analysis of possible phase transitions in inflationary universe. It is found that a restoration of the broken chiral symmetry takes place in two patterns for increasing curvature : the first order and second order phase transition respectively depending on initial settings of the four-body interaction parameter and the soft supersymmetry breaking parameter. The critical curves expressing the phase boundaries in these parameters are obtained. Cosmological implications of the result are discussed in connection with bubble formations and the creation of cosmic strings during the inflationary era.
Efficiency of the centrifugally induced curvature drift instability in AGN winds
Z. Osmanov
2008-05-09T23:59:59.000Z
For studying how the field lines are twisting nearby the light cylinder surface, which provides the free motion of AGN winds through the mentioned area, the investigation of the centrifugally driven curvature drift instability is presented. Studying the dynamics of the relativistic MHD flow close to the light cylinder surface, by applying a single particle approach based on the centrifugal acceleration, the dispersion relation of the instability is derived and analytically solved. Considering the typical values of AGN winds, it is shown that the time scale of the curvature drift instability is much less than the accretion process time scale, indicating that the present instability is very efficient and might strongly influence processes in AGN plasmas.
Influence of the bonding front propagation on the wafer stack curvature
Navarro, E. [SOITEC—Parc Technologique des Fontaines, 38190 Bernin (France); SIMaP—Grenoble-INP, 1340 rue de la Piscine, 38402 St. Martin d'Hčres (France); Bréchet, Y. [SIMaP—Grenoble-INP, 1340 rue de la Piscine, 38402 St. Martin d'Hčres (France); Barthelemy, A.; Radu, I. [SOITEC—Parc Technologique des Fontaines, 38190 Bernin (France); Pardoen, T. [Institute of Mechanics, Materials and Civil Engineering (iMMC), Université catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Raskin, J.-P. [Institute of Information and Communication Technologies, Electronics and Applied Mathematics (ICTEAM), Université catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium)
2014-08-11T23:59:59.000Z
The influence of the dynamics of the direct wafer bonding process on the curvature of the final wafer stack is investigated. An analytical model for the final curvature of the bonded wafers is developed, as a function of the different load components acting during the bonding front propagation, using thin plate theory and considering a strain discontinuity locked at the bonding interface. Experimental profiles are measured for different bonding conditions and wafer thicknesses. A very good agreement with the model prediction is obtained and the influence of the thin air layer trapped in-between the two wafers is demonstrated. The proposed model contributes to further improvement of the bonding process, in particular, for the stacking of layers of electronic devices, which requires a high accuracy of wafer-to-wafer alignment and a very low distortion level.
Influence of curvature on the device physics of thin film transistors on flexible substrates
Amalraj, Rex; Sambandan, Sanjiv, E-mail: sanjiv@iap.iisc.ernet.in [Flexible Electronics Lab, Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore 560012 (India)
2014-10-28T23:59:59.000Z
Thin film transistors (TFTs) on elastomers promise flexible electronics with stretching and bending. Recently, there have been several experimental studies reporting the behavior of TFTs under bending and buckling. In the presence of stress, the insulator capacitance is influenced due to two reasons. The first is the variation in insulator thickness depending on the Poisson ratio and strain. The second is the geometric influence of the curvature of the insulator-semiconductor interface during bending or buckling. This paper models the role of curvature on TFT performance and brings to light an elegant result wherein the TFT characteristics is dependent on the area under the capacitance-distance curve. The paper compares models with simulations and explains several experimental findings reported in literature.
Generalized strong curvature singularities and weak cosmic censorship in cosmological space-times
W. Rudnicki; R. J. Budzynski; W. Kondracki
2006-06-01T23:59:59.000Z
This paper is a further development of the approach to weak cosmic censorship proposed by the authors in Ref. 5. We state and prove a modified version of that work's main result under significantly relaxed assumptions on the asymptotic structure of space--time. The result, which imposes strong constraints on the occurrence of naked singularities of the strong curvature type, is in particular applicable to physically realistic cosmological models.
Surface tension and curvature energy of quark matter in the NJL model
G. Lugones; A. G. Grunfeld; M. Al Ajmi
2013-10-14T23:59:59.000Z
In this paper we study the surface tension and the curvature energy of three-flavor quark matter in equilibrium under weak interactions within the Nambu-Jona-Lasinio model. We include the effect of color superconductivity and describe finite size effects within the multiple reflection expansion (MRE) framework. Our calculations result in large values of the surface tension which disfavor the formation of mixed phases at the hadron-quark inter-phase inside a hybrid star.
SciDAC Center for Plasma Edge Simulation
Lin, Zhihong
2013-12-17T23:59:59.000Z
This project with a total funding of $592,998 for six years has partially supported four postdoctoral researchers at the University of California, Irvine (UCI). The UCI team has formulated electrostatic and electromagnetic global gyrokinetic particle simulation models with kinetic electrons, implemented these models in the edge code XGC1, performed benchmark between GTC and XGC1, developed computational tools for gyrokinetic particle simulation in tokamak edge geometry, and initiated preparatory study of edge turbulence using GTC code. The research results has been published in 12 papers and presented at many international and national conferences.
Stresses in thermally grown alumina scales near edges and corners.
Grimsditch, M.
1998-06-03T23:59:59.000Z
We have investigated the residual stress near edges and corners of thermally grown alumina scales. Micro-fluorescence measurements, performed on alloys with composition Fe-5Cr-28Al (at.%, bal. Fe) oxidized at 900 C, showed a large (>50%) reduction in hydrostatic stress in the vicinity of edges and corners. Surprisingly, stress relaxation persists out to distances ten times the scale thickness from the edge. Finite element analysis calculations confirm the experimental results and provide a considerably more detailed picture of the stress distribution and its components.
Improvement of the edge rotation diagnostic spectrum analysis via simulation
Luo, J.; Zhuang, G., E-mail: ge-zhuang@hust.edu.cn; Cheng, Z. F.; Zhang, X. L.; Hou, S. Y.; Cheng, C. [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)
2014-11-15T23:59:59.000Z
The edge rotation diagnostic (ERD) system has been developed on the Joint Texas Experimental Tokamak to measure the edge toroidal rotation velocity by observing the shifted wavelength of carbon V (C V 227.09 nm). Since the measured spectrum is an integrated result along the viewing line from the plasma core to the edge, a method via simulation has been developed to analyze the ERD spectrum. With the necessary parameters such as C V radiation profile and the ion temperature profile, a local rotation profile at the normalized minor radius of 0.5-1 is obtained.
Measurement of the curvature of a surface using parallel light beams
Chason, E.H.; Floro, J.A.; Seager, C.H.; Sinclair, M.B.
1999-06-15T23:59:59.000Z
Apparatus is disclosed for measuring curvature of a surface wherein a beam of collimated light is passed through a means for producing a plurality of parallel light beams each separated by a common distance which then reflect off the surface to fall upon a detector that measures the separation of the reflected beams of light. This means can be an etalon and the combination of a diffractive element and a converging lens. The curvature of the surface along the line onto which the multiple beams fall can be calculated from this information. A two-dimensional map of the curvature can be obtained by adding a second etalon (or a second combination of a diffractive element and a converging lens) which is rotated 90[degree] about the optical axis relative to the first etalon and inclined at the same angle. The second etalon creates an individual set of parallel light beams from each of the individual beams created by the first etalon with the sets of parallel light beams from the second etalon rotated 90[degree] relative to the line onto which the single set of parallel beams from the first etalon would have fallen. 5 figs.
Measurement of the curvature of a surface using parallel light beams
Chason, Eric H. (Sandia Park, NM); Floro, Jerrold A. (Edgewood, NM); Seager, Carleton H. (Albuquerque, NM); Sinclair, Michael B. (Albuquerque, NM)
1999-01-01T23:59:59.000Z
Apparatus for measuring curvature of a surface wherein a beam of collimated light is passed through means for producing a plurality of parallel light beams each separated by a common distance which then reflect off the surface to fall upon a detector that measures the separation of the reflected beams of light. This means can be an etalon and the combination of a diffractive element and a converging lens. The curvature of the surface along the line onto which the multiple beams fall can be calculated from this information. A two-dimensional map of the curvature can be obtained by adding a second etalon (or a second combination of a diffractive element and a converging lens) which is rotated 90.degree. about the optical axis relative to the first etalon and inclined at the same angle. The second etalon creates an individual set of parallel light beams from each of the individual beams created by the first etalon with the sets of parallel light beams from the second etalon rotated 90.degree. relative to the line onto which the single set of parallel beams from the first etalon would have fallen.
Yannouleas, Constantine
Graphene flakes with defective edge terminations: Universal and topological aspects, and one graphene nanoflakes with reconstructed zigzag edges, where a succes- sion of pentagons and heptagons these spectra. The electronic spectra of trigonal graphene nanoflakes with reczag edge terminations exhibit
The curvature of the wind profile as a factor in the formation of clear-air turbulence
Possiel, Norman Charles
1974-01-01T23:59:59.000Z
&N University; Chairman of Advisory Committee: Dr. James R. Scoggins This study concerns the importance of the curvature of the wind profile to the amplitude of mountain waves. Mechanisms favor- able for clear-air turbulence (CAT) are discussed in relation... to such wave motions. Relationships between CAT encountered in the stratosphere by an XB-70 aircraft over mountain-wave areas and the curvature of the wind profile in the troposphere, are studied. Expected mountain- wave areas are defined from topographical...
Moisture and temperature effects on curvature of anti-symmetric cross-ply graphite/epoxy laminates
Lott, Randall Stephen
1980-01-01T23:59:59.000Z
MOISTURE AND TEMPERATURE EFFECTS ON CURVATURE OF ANTI-SYMMETRIC CROSS-PLY GRAPHITE/EPOXY LAMINATES A Thesis by RANDALL STEPHEN LOTT Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE December 1980 Major Subject: Mechanical Engineering MOISTURE AND TEMPERATURE EFFECTS ON CURVATURE OF ANTI-SYMMETRIC CROSS-PLY GRAPHITE/EPOXY LAMINATES A Thesis by RANDALL STEPHEN LOTT Approved as to style and content...
Leading Edge Spinning the Web of Cell Fate
Corces, Victor G.
Leading Edge Minireview Spinning the Web of Cell Fate Kevin Van Bortle1 and Victor G. Corces1,* 1 involved in spinning the web of cell fate. Chromatin at the Nuclear Lamina The nuclear lamina is a thin
Topological p-n junctions in helical edge states
Disha Wadhawan; Poonam Mehta; Sourin Das
2014-11-24T23:59:59.000Z
Quantum spin Hall effect is endowed with topologically protected edge modes with gapless Dirac spectrum. Applying a magnetic field locally along the edge leads to a gapped edge spectrum with opposite parity for winding of spin texture for conduction and valence band. Using Pancharatnam's prescription for geometric phase it is shown that mismatch of this parity across a p-n junction, which could be engineered into the edge by electrical gate induced doping, leads to a phase dependence in the two-terminal conductance which is purely topological (0 or $\\pi$). This fact results in a ${\\mathbb{Z}}_2$ classification of such junctions with an associated duality. Current asymmetry measurements which are shown to be robust against electron-electron interactions are proposed to infer this topology.
TOWARD THE MINIMUM INNER EDGE DISTANCE OF THE HABITABLE ZONE
Zsom, Andras
We explore the minimum distance from a host star where an exoplanet could potentially be habitable in order not to discard close-in rocky exoplanets for follow-up observations. We find that the inner edge of the Habitable ...
Edge-based Meshless Methods for Compressible Flow Simulations
Jameson, Antony
are obtained for airfoils in transonic flow. Lift and drag coefficients also compare well to the finite volume, including (1) the application of certain artificial diffusion schemes to meshless methods within an edge
Theory for induced convection experiments in the tokamak edge
Theory for induced convection experiments in the tokamak edge P. Helander1 , D.D. Ryutov2 , and R National Laboratory, Livermore, USA By biasing alternate divertor plates in a tokamak, one can create
Characterizing the geometrical edges of nonlocal two-qubit gates
Balakrishnan, S
2009-01-01T23:59:59.000Z
Nonlocal two-qubit gates are geometrically represented by tetrahedron known as Weyl chamber within which the perfect entanglers form a polyhedron. We study the entangling power and local invariants of all the edges of the Weyl chamber and polyhedron. It is found that SWAP -alpha- family of gates with constitute one edge of the Weyl chamber. Using circuit equivalence, it is shown that Controlled-NOT can be constructed from SWAP-1/2, the only perfect entangler in the above family. Further, the three edges of the polyhedron possessing the entangling power of 1/6 are also capable of constructing CNOT. It is observed that all the edges of the geometry are formed by single parametric two-qubit gates.
Prototype FSP Center for Plasma Edge Simulation (CPES)
coupling math · SDM: Kepler work flow and dashboard, Data management · PERI: Performance enhancement* MHD Strauss* CS/Math Keyes* Organizational Chart Participants are listed once in blue, then, multiply.5/q3 Pedestal energy Edge physics (unkn
The edge observed : island landscape for a marine biology facility
Stringer, Geraldine A
1987-01-01T23:59:59.000Z
This thesis explores the concept of edges through observation and design. The intent of the observation/design is to understand and to illustrate possibilities for design that will enrich the experience of the built ...
Evolution of Landau levels into edge states in graphene
Li, Guohong
Two-dimensional electron systems in the presence of a magnetic field support topologically ordered states, in which the coexistence of an insulating bulk with conducting one-dimensional chiral edge states gives rise to the ...
3.3 Construction of vector edge elements
2011-10-05T23:59:59.000Z
Figure 3.1: Linear tetrahedral element. 3.3 Construction of vector edge elements. Let us first consider the linear tetrahedral element, as seen in Figure 3.1. Within.
Longfellow Middle School Edges Out Gildersleeve to Win 2011 Virginia...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Edges Out Gildersleeve to Win 2011 Virginia Middle School Science Bowl 1stplaceLongfellow.jpg The team from Longfellow Middle School, Falls Church, won the 2011 Virginia Regional...
Pure spin current induced by adiabatic quantum pumping in zigzag-edged graphene nanoribbons
Souma, Satofumi, E-mail: ssouma@harbor.kobe-u.ac.jp; Ogawa, Matsuto [Department of Electrical and Electronic Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501 (Japan)
2014-05-05T23:59:59.000Z
We show theoretically that pure spin current can be generated in zigzag edged graphene nanoribbons through the adiabatic pumping by edge selective pumping potentials. The origin of such pure spin current is the spin splitting of the edge localized states, which are oppositely spin polarized at opposite edges. In the proposed device, each edge of the ribbon is covered by two independent time-periodic local gate potentials with a definite phase difference, inducing the edge spin polarized current. When the pumping phase difference is opposite in sign between two edges, the total charge currents is zero and the pure edge spin current is generated.
Steamflood production mechanism in an edge pattern Duri field, Indonesia
Yuwono, Ipung Punto
1999-01-01T23:59:59.000Z
STEAMFLOOD PRODUCTION MECHANISM IN AN EDGE PATTERN DURI FIELD, INDONESIA A Thesis by IPUNG PUNTO YUWONO Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE December 1998 Major Subject: Petroleum Engineering STEAMFLOOD PRODUCTION MECHANISM IN AN EDGE PATTERN DURI FIELD, INDONESIA A Thesis by IPUNG PUNTO YUWONO Submitted to Texas AkM University in partial fulfillment of the requirements...
Oscillations of a Turbulent Jet Incident Upon an Edge
J.C. Lin; D. Rockwell
2000-09-19T23:59:59.000Z
For the case of a jet originating from a fully turbulent channel flow and impinging upon a sharp edge, the possible onset and nature of coherent oscillations has remained unexplored. In this investigation, high-image-density particle image velocimetry and surface pressure measurements are employed to determine the instantaneous, whole-field characteristics of the turbulent jet-edge interaction in relation to the loading of the edge. It is demonstrated that even in absence of acoustic resonant or fluid-elastic effects, highly coherent, self-sustained oscillations rapidly emerge above the turbulent background. Two clearly identifiable modes of instability are evident. These modes involve large-scale vortices that are phase-locked to the gross undulations of the jet and its interaction with the edge, and small-scale vortices, which are not phase-locked. Time-resolved imaging of instantaneous vorticity and velocity reveals the form, orientation, and strength of the large-scale concentrations of vorticity approaching the edge in relation to rapid agglomeration of small-scale vorticity concentrations. Such vorticity field-edge interactions exhibit rich complexity, relative to the simplified pattern of vortex-edge interaction traditionally employed for the quasi-laminar edgetone. Furthermore, these interactions yield highly nonlinear surface pressure signatures. The origin of this nonlinearity, involving coexistence of multiple frequency components, is interpreted in terms of large- and small-scale vortices embedded in distributed vorticity layers at the edge. Eruption of the surface boundary layer on the edge due to passage of the large-scale vortex does not occur; rather apparent secondary vorticity concentrations are simply due to distension of the oppositely-signed vorticity layer at the tip of the edge. The ensemble-averaged turbulent statistics of the jet quickly take on an identity that is distinct from the statistics of the turbulent boundary layer in the channel. Large increases in Reynolds stress occur due to onset of the small-scale concentrations of vorticity immediately downstream of separation; substantial increases at locations further downstream arise from development of the large-scale vorticity concentrations.
Intrinsic Dirac Behavior of Scalar Curvature in a Quaternionic Weyl-Cartan Geometry
J. E. Rankin
2015-03-18T23:59:59.000Z
The "spin-up" and "spin-down" projections of the second order, chiral form of Dirac Theory are shown to fit a superposition of forms predicted in an earlier classical, complex scalar gauge theory (April, 1992 Class. Quantum Grav.). In some sense, it appears to be possible to view the two component Dirac spinor as a single component, quaternionic, spacetime scalar. "Spin space" transformations become transformations of the internal quaternion basis. Essentially, quaternionic Dirac Theory projects into the complex plane neatly, where spin becomes related to the self-dual antisymmetric part of the metric. The correct Dirac eigenvalues and well-behaved eigenfunctions project intact into a pair of complex solutions for the scalar curvature in the earlier theory's Weyl-Cartan type geometry. Some estimates are made for predicted, interesting atomic and subatomic scale phenomena. A form of electromagnetic quanta appears. A generalization of the complex geometric structure is then sketched in an appendix that allows quaternionic gauges and curvatures, as well as some Weyl nonmetricity mixed with torsion. It appears to be a well defined structure, and leads to the full, second order, quaternionic Dirac Equation form, and a first order equation for a closely related, auxiliary wavefunction. A family of "free particle" solutions is examined in the Lorentzian limit of the symmetric part of the metric, including evaluation of the quaternionic scalar curvature from the wavefunctions. More generally, when limited to two quaternion dimensions (just two components), reasonably similar solutions can clearly be superposed linearly into new solutions, and separate naturally into two families with different commutation characteristics.
Deeper discussion of Schroedinger invariant and logarithmic sectors of higher-curvature gravity
Ayon-Beato, Eloy; Giribet, Gaston; Hassaiene, Mokhtar [Departamento de Fisica, CINVESTAV-IPN, Apdo. Postal 14-740, 07000, Mexico D.F. (Mexico); Instituto de Fisica de Buenos Aires IFIBA - CONICET, Buenos Aires (Argentina); Instituto de Matematica y Fisica, Universidad de Talca, Casilla 747, Talca, Chile and Laboratoire de Mathematiques et de Physique Theorique, Universite de Tours, Parc de Grandmont, 37200 Tours (France)
2011-05-15T23:59:59.000Z
The aim of this paper is to explore D-dimensional theories of pure gravity whose space of solutions contains a certain class of anti-de Sitter waves including, in particular, Schroedinger invariant spacetimes. This leads to consider higher-order theories, and the natural case to start with is to analyze generic square-curvature corrections to the Einstein-Hilbert action. In this case, the Schroedinger invariant sector in the space of solutions arises for a special relation between the coupling constants appearing in the action. On the other hand, besides the Schroedinger invariant configurations, logarithmic branches similar to those of the so-called log-gravity are also shown to emerge for another special choice of the coupling constants. Interestingly enough, these log solutions can be interpreted as the superposition of the massless mode of general relativity and two scalar modes that saturate the Breitenlohner-Freedman (BF) bound of the AdS space on which they propagate. These solutions are higher-dimensional analogues of those appearing in three-dimensional massive gravities with relaxed AdS{sub 3} asymptotic, which are candidates to be gravity duals for logarithmic conformal field theories (CFTs). Other sectors of the space of solutions of higher-curvature theories correspond to oscillatory configurations, which happen to be below the BF bound. Also, there is a fully degenerated sector, for which any wave profile is admitted. We comment on the relation between this degeneracy and the nonrenormalizability of the dynamical exponent of the Schroedinger spaces. Our analysis also includes more general gravitational actions with nonpolynomial corrections consisting of arbitrary functions of the square-curvature invariants. By establishing a correspondence with the quadratic gravity model, the same sectors of solutions are shown to exist for this more general family of theories. We finally consider the parity-violating Chern-Simons modified gravity in four dimensions, for which we derive both the Schroedinger invariant as well as the logarithmic sectors.
Curvature and torsion effects in electric current-carrying twisted solar loops
Garcia de Andrade, L. C. [Departamento de Fisica Teorica-IF-UERJ, Rua Sao Francisco Xavier 524, Rio de Janeiro, RJ Maracana, CEP 20550-013 Brazil (Brazil)
2006-11-15T23:59:59.000Z
Riemannian geometry of the electric current-carrying solar loops is obtained from a thin tube approximation of twisted magnetic flux tubes. The Frenet torsion and curvature affect the electron drift speed of the electrons of the current along the toroidal direction of the tube. The twist of the tube is computed and it is shown that twist is maximum at the surface of the tube and minimum at the tube axis. This acts as inertia effects to the electron drift. The higher the torsion of the tube axis the smaller is the velocity along the direction of the tube. This effect is similar to the one obtained by Tyspin et al. [Physics of Plasmas, 5, 3385 (1998)] in the case of toroidal devices with curvature and torsion. Here the simple geometrical effects are enough to slow down the currents and no viscosity in the fluid is taken into account. A slight compressibility of the plasma flow is due to the twist of the tube. As applications of these ideas, it is shown that torsion effects are not enough to accelerate electrons up to relativistic energies, and the torsion is computed in the case of the force-free loop. The value of torsion is used to compute the electron acceleration in two distinct cases. The first is the case when the Riemann loop suffers the action of a dc electric sub-Dreicer field, where the magnetic field is direct along the magnetic loop, and the loop moves along the orthogonal direction to the loop as in vortex filaments. In this case, the acceleration is shown to be of the order of 10{sup -17} cm s{sup -2} for a solar torsion of the order of 10{sup -4} cm{sup -1}. The second case is for the curvature drift contribution, where torsion is also present. In this case we show that torsion is not present in the velocity drift but just in the electron acceleration. Though these values are extremely low, they can be improved by considering small loops lowering the radius of the loop which, here, was taken as 600 km. Curvature drift acceleration is also estimated as 100 cm s{sup -2}.
Iso-curvature fluctuations through axion trapping by cosmic string wakes
Biswanath Layek
2005-03-07T23:59:59.000Z
We consider wake-like density fluctuations produced by cosmic strings at the quark-hadron transition in the early universe. We show that low momentum axions which are produced through the radiation from the axionic string at an earlier stage, may get trapped inside these wakes due to delayed hadronization in these overdense regions. As the interfaces, bordering the wakes, collapse, the axions pick-up momentum from the walls and finally leave the wake regions. These axions thus can produce large scale iso-curvature fluctuations. We have calculated the detailed profile of these axionic density fluctuations and discuss its astrophysical consequences.
Compensation for large tensor modes with iso-curvature perturbations in CMB anisotropies
Masahiro Kawasaki; Shuichiro Yokoyama
2014-04-23T23:59:59.000Z
Recently, BICEP2 has reported the large tensor-to-scalar ratio $r=0.2^{+0.07}_{-0.05}$ from the observation of the cosmic microwave background (CMB) B-mode at degree-scales. Since tensor modes induce not only CMB B-mode but also the temperature fluctuations on large scales, to realize the consistent temperature fluctuations with the Planck result we should consider suppression of scalar perturbations on corresponding large scales. To realize such a suppression, we consider anti-correlated iso-curvature perturbations which could be realized in the simple curvaton model.
Compensation for large tensor modes with iso-curvature perturbations in CMB anisotropies
Kawasaki, Masahiro
2014-01-01T23:59:59.000Z
Recently, BICEP2 has reported the large tensor-to-scalar ratio $r=0.2^{+0.07}_{-0.05}$ from the observation of the cosmic microwave background (CMB) B-mode at degree-scales. Since tensor modes induce not only CMB B-mode but also the temperature fluctuations on large scales, to realize the consistent temperature fluctuations with the Planck result we should consider suppression of scalar perturbations on corresponding large scales. To realize such a suppression, we consider anti-correlated iso-curvature perturbations which could be realized in the simple curvaton model.
Core Microturbulence and Edge MHD Interplay and Stabilization by Fast Ions in Tokamak Confined Plasmas
CONTINUOUS EDGE GRADIENT-BASED TEMPLATE MATCHING FOR ARTICULATED OBJECTS
Daniel Mohr; Gabriel Zachmann
template matching, deformable object detection, confidence map, edge feature, graphics hardware In this paper, we propose a novel edge gradient based template matching method for object detection. In contrast to other methods, ours does not perform any binarization or discretization during the online matching. This is facilitated by a new continuous edge gradient similarity measure. Its main components are a novel edge gradient operator, which is applied to query and template images, and the formulation as a convolution, which can be computed very efficiently in Fourier space. We compared our method to a state-of-the-art chamfer based matching method. The results demonstrate that our method is much more robust against weak edge response and yields much better confidence maps with fewer maxima that are also more significant. In addition, our method lends itself well to efficient implementation on GPUs: at a query image resolution of 320 × 256 and a template resolution of 80 × 80 we can generate about 330 confidence maps per second. 1
Path Curvature Discrimination: Dependence on Gaze Direction and Optical Flow Speed
the first to record gaze behavior during curve driving on a road clearly delineated by edge-lines of the visual system, as predicted by our model. The spontaneous gazing strategies observed during driving might on a daily basis, when walking in the street or driving on a winding road. Among other sources of information
Ramiro dell'Erba; Francesco dell'Isola; Giacomo Rotoli
2010-07-09T23:59:59.000Z
We evaluate how the curvature dependence of surface tension affects the shape of electrically charged interfaces between a perfectly conducting fluid and its vapour. We consider two cases: i) spherical droplets in equilibrium with their vapour; ii) menisci pending in a capillary tube in presence of a conducting plate at given electric potential drop. Tolman-like dependence of surface tension on curvature becomes important when the "nucleation radius" is comparable with the interface curvature radius. In case i) we prove existence of the equilibrium minimal radius and estimate its dependence on the electric field and Tolmanlike curvature effects. In case ii) the menisci are subject to the gravitational force, surface tension and electrostatic fields We determine the unknown surface of the menisci to which the potential is assigned using an iterative numerical method and show that Tolman-like corrections imply: 1) a variation of the height (up to 10% in some cases) of the tip of the menisci; 2) a decrease of the maximum electrical potential applicable to the menisci before their breakdown amounting to 40V over 800V in the considered cases. We conjecture that these effects could be used in new experiments based on electric measurements to determine the dependence of the equilibrium surface tension on curvature
A survey of problems in divertor and edge plasma theory
Boozer, A. [Coll. of William and Mary, Williamsburg, VA (United States); Braams, B.; Weitzner, H. [New York Univ., NY (United States). Courant Inst. of Mathematical Sciences; Cohen, R. [Lawrence Livermore National Lab., CA (United States); Hazeltine, R. [Texas Univ., Austin, TX (United States). Inst. for Fusion Studies; Hinton, F. [General Atomics, San Diego (United States); Houlberg, W. [Oak Ridge National Lab., TN (United States); Oktay, E.; Sadowski, W. [USDOE Office of Energy Research, Washington, DC (United States). Office of Fusion Energy; Post, D. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Sigmar, D. [Massachusetts Inst. of Tech., Cambridge, MA (United States); Wootton, A. [Texas Univ., Austin, TX (United States). Center for Plasma Physics and Thermonuclear Research
1992-12-22T23:59:59.000Z
Theoretical physics problems related to divertor design are presented, organized by the region in which they occur. Some of the open questions in edge physics are presented from a theoretician`s point of view. After a cursory sketch of the fluid models of the edge plasma and their numerical realization, the following topics are taken up: time-dependent problems, non-axisymmetric effects, anomalous transport in the scrape-off layer, edge kinetic theory, sheath effects and boundary conditions in divertors, electric field effects, atomic and molecular data issues, impurity transport in the divertor region, poloidally localized power dissipation (MARFEs and dense gas targets), helium ash removal, and neutral transport. The report ends with a summary of selected problems of particular significance and a brief bibliography of survey articles and related conference proceedings.
A survey of problems in divertor and edge plasma theory
Boozer, A. (Coll. of William and Mary, Williamsburg, VA (United States)); Braams, B.; Weitzner, H. (New York Univ., NY (United States). Courant Inst. of Mathematical Sciences); Cohen, R. (Lawrence Livermore National Lab., CA (United States)); Hazeltine, R. (Texas Univ., Austin, TX (United States). Inst. for Fusion Studies); Hinton, F. (General Atomics, San Diego (United States)); Houlberg, W. (Oak
1992-12-22T23:59:59.000Z
Theoretical physics problems related to divertor design are presented, organized by the region in which they occur. Some of the open questions in edge physics are presented from a theoretician's point of view. After a cursory sketch of the fluid models of the edge plasma and their numerical realization, the following topics are taken up: time-dependent problems, non-axisymmetric effects, anomalous transport in the scrape-off layer, edge kinetic theory, sheath effects and boundary conditions in divertors, electric field effects, atomic and molecular data issues, impurity transport in the divertor region, poloidally localized power dissipation (MARFEs and dense gas targets), helium ash removal, and neutral transport. The report ends with a summary of selected problems of particular significance and a brief bibliography of survey articles and related conference proceedings.
Predicting the Performance of Edge Seal Materials for PV (Presentation)
Kempe, M.; Panchagade, D.; Dameron, A.; Reese, M.
2012-03-01T23:59:59.000Z
Edge seal materials were evaluated using a 100-nm film of Ca deposited on glass and laminated to another glass substrate. As moisture penetrates the package it converts the Ca metal to transparent CaOH2 giving a clear indication of the depth to which moisture has entered. Using this method, we have exposed test samples to a variety of temperature and humidity conditions ranging from 45C and 10% RH up to 85C and 85% RH, to ultraviolet radiation and to mechanical stress. We are able to show that edge seal materials are capable of keeping moisture away from sensitive cell materials for the life of a module.
Flexible edge seal for vacuum insulating glazing units
Bettger, Kenneth J.; Stark, David H.
2012-12-11T23:59:59.000Z
A flexible edge seal is provided for a vacuum insulating glazing unit having a first glass pane and a second glass pane spaced-apart from the first. The edge seal comprises a seal member formed of a hermetically bondable material and having a first end, a second end and a center section disposed therebetween. The first end is hermetically bondable to a first glass pane. The second end is hermetically bondable to a second glass pane. The center section comprises a plurality of convolutes.
Method and system for edge cladding of laser gain media
Bayramian, Andrew James; Caird, John Allyn; Schaffers, Kathleen Irene
2014-03-25T23:59:59.000Z
A gain medium operable to amplify light at a gain wavelength and having reduced transverse ASE includes an input surface and an output surface opposing the input surface. The gain medium also includes a central region including gain material and extending between the input surface and the output surface along a longitudinal optical axis of the gain medium. The gain medium further includes an edge cladding region surrounding the central region and extending between the input surface and the output surface along the longitudinal optical axis of the gain medium. The edge cladding region includes the gain material and a dopant operable to absorb light at the gain wavelength.
Chakraborty, N. [Engineering Department, University of Liverpool, Brownlow Hill, Liverpool L69 3GH (United Kingdom); Hawkes, E.R. [School of Photovoltaic and Renewable Energy Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); Chen, J.H. [Combustion Research Facility, Sandia National Laboratories, Livermore, CA 94551 (United States); Cant, R.S. [Engineering Department, Cambridge University, Trumpington Street, Cambridge CB2 1PZ (United Kingdom)
2008-07-15T23:59:59.000Z
The effects of tangential strain rate and curvature on the surface density function (SDF) and on source terms within the SDF transport equation are studied for lean methane-air and hydrogen-air flames using two-dimensional direct numerical simulations with detailed chemistry. A positive correlation is observed between the SDF and the tangential strain rate, and this is explained in terms of the interaction between the local tangential strain rate and the dilatation rate due to heat release. Curvature is also seen to affect the SDF through the curvature response of both tangential strain rate and dilatation rate on a given flame isosurface. Strain rate and curvature are found to have an appreciable effect on several terms of the SDF transport equation. The SDF straining term in both methane and hydrogen flames is correlated positively with tangential strain rate, as expected, and is also correlated negatively with curvature. For methane flames, the SDF propagation term is found to correlate negatively with flame curvature toward the reactant side of the flame and positively toward the product side. By contrast, for hydrogen flames the SDF propagation term is negatively correlated with curvature throughout the flame brush. The variation of the SDF curvature term with local flame curvature for both methane and hydrogen flames is found to be nonlinear due to the additional stretch induced by the tangential diffusion component of the displacement speed. Physical explanations are provided for all of these effects, and the modeling implications are considered in detail. (author)
Stachowiak, Jeanne C.; Hayden, Carl C.; Negrete, Oscar A.; Davis, Ryan Wesley; Sasaki, Darryl Yoshio
2013-10-01T23:59:59.000Z
Pathogenic viruses are a primary threat to our national security and to the health and economy of our world. Effective defense strategies to combat viral infection and spread require the development of understanding of the mechanisms that these pathogens use to invade the host cell. We present in this report results of our research into viral particle recognition and fusion to cell membranes and the role that protein affinity and confinement in lipid domains plays in membrane curvature in cellular fusion and fission events. Herein, we describe 1) the assembly of the G attachment protein of Nipah virus using point mutation studies to define its role in viral particle fusion to the cell membrane, 2) how lateral pressure of membrane bound proteins induce curvature in model membrane systems, and 3) the role of membrane curvature in the selective partitioning of molecular receptors and specific affinity of associated proteins.
Exact charged black-hole solutions in D-dimensional f(T) gravity: torsion vs curvature analysis
Capozziello, Salvatore; Saridakis, Emmanuel N; Vasquez, Yerko
2012-01-01T23:59:59.000Z
We extract exact charged black-hole solutions with flat transverse sections in the framework of D-dimensional Maxwell-f(T) gravity, and we analyze the singularities and horizons based on both torsion and curvature invariants. Interestingly enough, we find that in some particular solution subclasses there appear more singularities in the curvature scalars than in the torsion ones. This difference disappears in the uncharged case, or in the case where f(T) gravity becomes the usual linear-in-T teleparallel gravity, that is General Relativity. Curvature and torsion invariants behave very differently when matter fields are present, and thus f(R) gravity and f(T) gravity exhibit different features and cannot be directly re-casted each other.
Exact charged black-hole solutions in D-dimensional f(T) gravity: torsion vs curvature analysis
Salvatore Capozziello; P. A. Gonzalez; Emmanuel N. Saridakis; Yerko Vasquez
2012-10-03T23:59:59.000Z
We extract exact charged black-hole solutions with flat transverse sections in the framework of D-dimensional Maxwell-f(T) gravity, and we analyze the singularities and horizons based on both torsion and curvature invariants. Interestingly enough, we find that in some particular solution subclasses there appear more singularities in the curvature scalars than in the torsion ones. This difference disappears in the uncharged case, or in the case where f(T) gravity becomes the usual linear-in-T teleparallel gravity, that is General Relativity. Curvature and torsion invariants behave very differently when matter fields are present, and thus f(R) gravity and f(T) gravity exhibit different features and cannot be directly re-casted each other.
How the permutation of edges of a metric graph affects the number of points moving along the edges
V. L. Chernyshev; A. A. Tolchennikov
2014-10-18T23:59:59.000Z
We consider a dynamical system on a metric graph, that corresponds to a semiclassical solution of a time-dependent Schr\\"odinger equation. We omit all details concerning mathematical physics and work with a purely discrete problem. We find a weak inequality representation for the number of points coming out of the vertex of an arbitrary tree graph. We apply this construction to an "H-junction" graph. We calculate the difference between numbers of moving points corresponding to the permutation of edges. Then we find a symmetrical difference of the number of points moving along the edges of a metric graph.
SciDAC-Center for Plasma Edge Simulation
Chang, Choong Seock
2012-06-04T23:59:59.000Z
The SciDAC ProtoFSP Center for Plasma Edge Simulation (CPES) [http://www.cims.nyu.edu/cpes/] was awarded to New York University, Courant Institute of Mathematical Sciences in FY 2006. C.S. Chang was the institutional and national project PI. ItĂ˘Â?Â?s mission was 1) to build kinetic simulation code applicable to tokamak edge region including magnetic divertor geometry, 2) to build a computer science framework which can integrate the kinetic code with MHD/fluid codes in multiscale, 3) to conduct scientific research using the developed tools. CPES has built two such edge kinetic codes XGC0 and XGC1, which are still the only working kinetic edge plasma codes capable of including the diverted magnetic field geometry. CPES has also built the code coupling framework EFFIS (End-to-end Framework for Fusion Integrated Simulation), which incubated and used the Adios (www.olcf.ornl.gov/center-projects/adios/) and eSiMon (http://www.olcf.ornl.gov/center-projects/esimmon/) technologies, together with the Kepler technology.
Hierarchical regularization for edge-preserving reconstruction of PET images
Bardsley, John
Hierarchical regularization for edge-preserving reconstruction of PET images Johnathan M. Bardsley.somersalo@case.edu Abstract. The data in PET emission and transmission tomography and in low dose X-ray tomography, consists that the algorithm gives good quality reconstructions for both emission and transmission PET problems in an efficient
Hierarchical regularization for edge-preserving reconstruction of PET images
Bardsley, John
1 Hierarchical regularization for edge-preserving reconstruction of PET images Johnathan M. Bardsley , Daniela Calvetti, and Erkki Somersalo Abstract--The data in PET emission and transmission tomog for both emission and transmission PET problems at very low computational cost. Index Terms
Gravitational lensing of quasars by edge-on spiral galaxies
Wang, Emily P
2007-01-01T23:59:59.000Z
In this thesis, I studied the lensed quasar CX2201-3201, which is lensed by an edge-on spiral galaxy. The unusually high tilt of the spiral galaxy provides us with a rare opportunity for mass modeling. In addition, the ...
Leading Edge Nuclear Biology: What's Been Most Surprising?
Pikaard, Craig
Leading Edge Voices Nuclear Biology: What's Been Most Surprising? Restricting Genomic Partners Job with inappropriate elements. So, a major question in the field of nuclear organization is how do cells ensure have demonstrated that thousands of regulatory regions undergo activation or decommissioning even
The brain near the edge Dante R. Chialvo
Chialvo, Dante R.
The brain near the edge Dante R. Chialvo Department of Physiology, Feinberg Medical School grain, the brain seems a relatively small dynamical system composed by a few dozen interacting areas that some of the most fundamental properties of the functioning brain are possible because
Edge Detection in Digital Image Processing Debosmit Ray
Morrow, James A.
Edge Detection in Digital Image Processing Debosmit Ray Thursday, June 06, 2013. 1. Introduction In this paper, I discuss the mathematical theorems and algorithms used in image processing. Digital Image Processing is the use of com- puter algorithms to perform image processing on digital images. Since the use
FACETS: Framework Application for Core-Edge Transport Simulations
-institutional main project: Tech-X (Physics, CS/AM); LLNL (Physics, CS/AM); PPPL (Physics); ANL (CS/AM); UCSD (Physics); CSU (AM); ORNL (CS, perf); ParaTools (CS, perf) · Appended SAP: GA, ORNL · Advisory: Columbia transitions · Core is a collisionless, 1D transport system with local, only-cross-surface fluxes · Edge
Towards intrinsic magnetism of graphene sheets with irregular zigzag edges
Wang, Wei Hua
Towards intrinsic magnetism of graphene sheets with irregular zigzag edges Lianlian Chen, Liwei Guo Academy of Sciences, P.O. Box 603, Beijing 100190, China. The magnetism of graphene has remained divergent and controversial due to absence of reliable experimental results. Here we show the intrinsic magnetism of graphene
On Plane Bipartite Graphs without Fixed Edges Khaled Salem*
Klavzar, Sandi
cycle. Randi [12, 13] used alternating cycles (or conjugated circuits) to estimate resonance energies face is an alternating cycle. Moreover, a polyhex fragment has no fixed edges if and only if the boundaries of its infinite face and the non-hexagonal finite faces are alternating cycles. These results
Continuous Edge Gradient-Based Template Matching for Articulated
Zachmann, Gabriel
Zachmann IfI Technical Report Series IfI-09-01 #12;Impressum Publisher: Institut fĂĽr Informatik, Technische (Technical Computer Science) Prof. Dr. Gabriel Zachmann (Computer Graphics) #12;Continuous Edge Gradient-Based Template Matching for Articulated Objects Daniel Mohr and Gabriel Zachmann Abstract Detection
Degenerate band edges in optical fiber with multiple
the forward energy fluxes S of the two media defines the coupling efficiency Ľ S2=S1. For PBG materialsDegenerate band edges in optical fiber with multiple grating: efficient coupling to slow light), School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia 2 CUDOS, School
Edge-Localized Iterative Reconstruction for Computed Tomography
1 Edge-Localized Iterative Reconstruction for Computed Tomography Zhou Yu Student Member, IEEE) can greatly improve the quality of computed tomography (CT) images. In particular, MBR can recover at significantly reduced computational cost. Index Terms--Computed tomography, model based reconstruc- tion
Edge-Localized Iterative Reconstruction for Computed Tomography
Edge-Localized Iterative Reconstruction for Computed Tomography Zhou Yu Student Member, IEEE, Jean the quality of computed tomography (CT) images. In particular, MBR can recover fine details and small features reduced computational cost. Index Terms--Computed tomography, model based reconstruc- tion, coordinate
SciDAC - Center for Plasma Edge Simulation - Project Summary
Parker, Scott
2014-11-03T23:59:59.000Z
Final Technical Report: Center for Plasma Edge Simulation (CPES) Principal Investigator: Scott Parker, University of Colorado, Boulder Description/Abstract First-principle simulations of edge pedestal micro-turbulence are performed with the global gyrokinetic turbulence code GEM for both low and high confinement tokamak plasmas. The high confinement plasmas show a larger growth rate, but nonlinearly a lower particle and heat flux. Numerical profiles are obtained from the XGC0 neoclassical code. XGC0/GEM code coupling is implemented under the EFFIS (“End-to-end Framework for Fusion Integrated Simulation”) framework. Investigations are underway to clearly identify the micro-instabilities in the edge pedestal using global and flux-tube gyrokinetic simulation with realistic experimental high confinement profiles. We use both experimental profiles and those obtained using the EFFIS XGC0/GEM coupled code framework. We find there are three types of instabilities at the edge: a low-n, high frequency electron mode, a high-n, low frequency ion mode, and possibly an ion mode like kinetic ballooning mode (KBM). Investigations are under way for the effects of the radial electric field. Finally, we have been investigating how plasmas dominated by ion-temperature gradient (ITG) driven turbulence, how cold Deuterium and Tritium ions near the edge will naturally pinch radially inward towards the core. We call this mechanism “natural fueling.” It is due to the quasi-neutral heat flux dominated nature of the turbulence and still applies when trapped and passing kinetic electron effects are included. To understand this mechanism, examine the situation where the electrons are adiabatic, and there is an ion heat flux. In such a case, lower energy particles move inward and higher energy particles move outward. If a trace amount of cold particles are added, they will move inward.
Zhou, X; Barta, M; Gan, W; Liu, S
2015-01-01T23:59:59.000Z
Aims: We investigate the electron acceleration in convective electric fields of cascading magnetic reconnection in a flaring solar corona and show the resulting hard X-ray (HXR) radiation spectra caused by Bremsstrahlung for the coronal source. Methods: We perform test particle calculation of electron motions in the framework of a guiding center approximation. The electromagnetic fields and their derivatives along electron trajectories are obtained by linearly interpolating the results of high-resolution adaptive mesh refinement (AMR) MHD simulations of cascading magnetic reconnection. Hard X-ray (HXR) spectra are calculated using an optically thin Bremsstrahlung model. Results: Magnetic gradients and curvatures in cascading reconnection current sheet accelerate electrons: trapped in magnetic islands, precipitating to the chromosphere and ejected into the interplanetary space. The final location of an electron is determined by its initial position, pitch angle and velocity. These initial conditions also influ...
Giant adsorption of microswimmers: duality of shape asymmetry and wall curvature
Wysocki, Adam; Gompper, Gerhard
2015-01-01T23:59:59.000Z
The effect of shape asymmetry of microswimmers on their adsorption capacity at confining channel walls is studied by a simple dumbbell model. For a shape polarity of a forward-swimming cone, like the stroke-averaged shape of a sperm, extremely long wall retention times are found, caused by a non-vanishing component of the propulsion force pointing steadily into the wall, which grows exponentially with the self-propulsion velocity and the shape asymmetry. A direct duality relation between shape asymmetry and wall curvature is proposed and verified. Our results are relevant for the design microswimmer with controlled wall-adhesion properties. In addition, we confirm that pressure in active systems is strongly sensitive to the details of the particle-wall interactions.
Matter as Curvature and Torsion of General Metric-Affine Space
Alex Karpelson
2014-06-25T23:59:59.000Z
General equations of the unified geometric field theory, based on the curved and torsional space-time, are presented. They contain only geometrical parameters of the metric-affine space G4 and describe distribution and motion of the matter, which represents curvature and torsion of the space-time. Equations describing spherically symmetric non-stationary and stationary fields are derived for various cases: for metrics with singularities and without them, for gravitational field in vacuum and for the massless fluid with spin. Equations describing uniform isotropic field are derived for the closed and open isotropic models of universe for the gravitational field in vacuum and for the massless fluid with spin; some of these equations and their solutions coincide with the respective equations and their solutions in general relativity for the space filled with the dust-like matter.
New massive gravity extended with an arbitrary number of curvature corrections
Paulos, Miguel F. [Department of Applied Mathematics and Theoretical Physics, Cambridge CB3 0WA (United Kingdom)
2010-10-15T23:59:59.000Z
We consider new massive gravity (NMG) type models in the context of AdS/CFT. By demanding the existence of a holographic c theorem, we construct an infinite family of three-dimensional quantum gravity models, generalizing the NMG Lagrangian to arbitrarily high order in curvatures. We calculate the central charge c and show that using Cardy's formula it matches the entropy of black hole solutions. We also consider fluctuations about an anti-de Sitter background, finding ghostlike massive modes as in NMG. However, these can (a) be made massless by setting c=0, in which case these Lagrangians are expected to provide gravity duals for strongly coupled logarithmic conformal field theories, (b) be eliminated by imposing a single constraint on the parameters of the Lagrangian, thereby obtaining an infinite family of theories with the same perturbative content of three-dimensional general relativity.
Bose-Einstein Condensation on a Manifold with Nonnegative Ricci Curvature
Levent Akant; Emine Ertugrul; Ferzan Tapramaz; O. Teoman Turgut
2014-03-28T23:59:59.000Z
The Bose-Einstein condensation for an ideal Bose gas and for a dilute weakly interacting Bose gas in a manifold with nonnegative Ricci curvature is investigated using the heat kernel and eigenvalue estimates of the Laplace operator. The main focus is on the nonrelativistic gas. However, special relativistic ideal gas is also discussed. The thermodynamic limit of the heat kernel and eigenvalue estimates is taken and the results are used to derive bounds for the depletion coefficient. In the case of a weakly interacting gas Bogoliubov approximation is employed. The ground state is analyzed using heat kernel methods and finite size effects on the ground state energy are proposed. The justification of the c-number substitution on a manifold is given.
The importance of ion size and electrode curvature on electrical double layers in ionic liquids
Feng, G.; Qiao, R.; Huang, J; Dai, S.; Sumpter, B. G.; Meunier, V.
2011-01-01T23:59:59.000Z
Room-temperature ionic liquids (ILs) are an emerging class of electrolytes for supercapacitors. We investigate the effects of ion size and electrode curvature on the electrical double layers (EDLs) in two ILs 1-butyl-3-methylimidazolium chloride [BMIM][Cl] and 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF{sub 6}], using a combination of molecular dynamics (MD) and quantum density functional theory (DFT) simulations. The sizes of the counter-ion and co-ion affect the ion distribution and orientational structure of EDLs. The EDL capacitances near both planar and cylindrical electrodes were found to follow the order: [BMIM][Cl] (near the positive electrode) > [BMIM][PF{sub 6}] (near the positive electrode) ? [BMIM][Cl] (near the negative electrode) ? [BMIM][PF{sub 6}] (near the negative electrode). The EDL capacitance was also found to increase as the electrode curvature increases. These capacitance data can be fit to the Helmholtz model and the recently proposed exohedral electrical double-cylinder capacitor (xEDCC) model when the EDL thickness is properly parameterized, even though key features of the EDLs in ILs are not accounted for in these models. To remedy the shortcomings of existing models, we propose a “Multiple Ion Layers with Overscreening” (MILO) model for the EDLs in ILs that takes into account two critical features of such EDLs, i.e., alternating layering of counter-ions and co-ions and charge overscreening. The capacitance computed from the MILO model agrees well with the MD prediction. Although some input parameters of the MILO model must be obtained from MD simulations, the MILO model may provide a new framework for understanding many important aspects of EDLs in ILs (e.g., the variation of EDL capacitance with the electrode potential) that are difficult to interpret using classical EDL models and experiments.
The Importance of Ion Size and Electrode Curvature on Electrical Double Layers in Ionic Liquids
Feng, Guang [Clemson University; Qiao, Rui [ORNL; Huang, Jingsong [ORNL; Dai, Sheng [ORNL; Sumpter, Bobby G [ORNL; Meunier, Vincent [ORNL
2010-01-01T23:59:59.000Z
Room-temperature ionic liquids (ILs) are an emerging class of electrolytes for supercapacitors. We investigate the effects of ion size and electrode curvature on the electrical double layers (EDLs) in two ILs 1-butyl-3-methylimidazolium chloride [BMIM][Cl] and 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF(6)], using a combination of molecular dynamics (MD) and quantum density functional theory (DFT) simulations. The sizes of the counter-ion and co-ion affect the ion distribution and orientational structure of EDLs. The EDL capacitances near both planar and cylindrical electrodes were found to follow the order: [BMIM][Cl] (near the positive electrode) > [BMIM][PF(6)] (near the positive electrode) {approx} [BMIM][Cl] (near the negative electrode) {approx} [BMIM][PF(6)] (near the negative electrode). The EDL capacitance was also found to increase as the electrode curvature increases. These capacitance data can be fit to the Helmholtz model and the recently proposed exohedral electrical double-cylinder capacitor (xEDCC) model when the EDL thickness is properly parameterized, even though key features of the EDLs in ILs are not accounted for in these models. To remedy the shortcomings of existing models, we propose a 'Multiple Ion Layers with Overscreening' (MILO) model for the EDLs in ILs that takes into account two critical features of such EDLs, i.e., alternating layering of counter-ions and co-ions and charge overscreening. The capacitance computed from the MILO model agrees well with the MD prediction. Although some input parameters of the MILO model must be obtained from MD simulations, the MILO model may provide a new framework for understanding many important aspects of EDLs in ILs (e.g., the variation of EDL capacitance with the electrode potential) that are difficult to interpret using classical EDL models and experiments.
Ward, Charles A.
Effect of Contact Line Curvature on Solid-Fluid Surface Tensions Without Line Tension C. A. Ward neglected adsorption at the solid-liquid interface and its effect on the surface tension of this interface-liquid interface can be determined, as can the surface tensions of the solid-liquid and solid-vapor interfaces. DOI
Wood, Robert
. This sensor represents the first use of liquid-embedded elastomer electronics to monitor human or robotic and robot kinematics. (a) An illustration of a human hand covered with curvature sensors at every joint and stretchable, they can conform to joint rotations and will not interfere with the mechanics of body movement
Karasic, Thomas B.; Hei, Tom K. [Center for Radiological Research, Department of Radiation Oncology, College of Physicians and Surgeons, Columbia University, New York, NY 10032 (United States)] [Center for Radiological Research, Department of Radiation Oncology, College of Physicians and Surgeons, Columbia University, New York, NY 10032 (United States); Ivanov, Vladimir N., E-mail: vni3@columbia.edu [Center for Radiological Research, Department of Radiation Oncology, College of Physicians and Surgeons, Columbia University, New York, NY 10032 (United States)
2010-07-15T23:59:59.000Z
Resistance of cancer cells to apoptosis is dependent on a balance of multiple genetic and epigenetic mechanisms, which up-regulate efficacy of the surviving growth factor-receptor signaling pathways and suppress death-receptor signaling pathways. The Insulin-like Growth Factor-1 Receptor (IGF-1R) signaling pathway is highly active in metastatic melanoma cells by mediating downstream activation of PI3K-AKT and MAPK pathways and controlling general cell survival and proliferation. In the present study, we used human melanoma lines with established genotypes that represented different phases of cancer development: radial-growth-phase WM35, vertical-growth-phase WM793, metastatic LU1205 and WM9 [1]. All these lines have normal NRAS. WM35, WM793, LU1205 and WM9 cells have mutated BRAF (V600E). WM35 and WM9 cells express normal PTEN, while in WM793 cells PTEN expression is down-regulated; finally, in LU1205 cells PTEN is inactivated by mutation. Cyclolignan picropodophyllin (PPP), a specific inhibitor of IGF-1R kinase activity, strongly down-regulated the basal levels of AKT activity in WM9 and in WM793 cells, modestly does so in LU1205, but has no effect on AKT activity in the early stage WM35 cells that are deficient in IGF-1R. In addition, PPP partially down-regulated the basal levels of active ERK1/2 in all lines used, highlighting the role of an alternative, non-BRAF pathway in MAPK activation. The final result of PPP treatment was an induction of apoptosis in WM793, WM9 and LU1205 melanoma cells. On the other hand, dose-dependent inhibition of IGF-1R kinase activity by PPP at a relatively narrow dose range (near 500 nM) has different effects on melanoma cells versus normal cells, inducing apoptosis in cancer cells and G2/M arrest of fibroblasts. To further enhance the pro-apoptotic effects of PPP on melanoma cells, we used a combined treatment of TNF-Related Apoptosis-Inducing Ligand (TRAIL) and PPP. This combination substantially increased death by apoptosis for WM793 and WM9 cells, but did so only modestly for LU1205 cells with very high basal activity of AKT. The ultimate goal of this direction of research is the discovery of a new treatment method for highly resistant human metastatic melanomas. Our findings provide the rationale for further preclinical evaluation of this novel treatment.
López-Barrera, Fabiola
Forest edges created by scattered-patch clear-cutting have become a common landscape feature in tropical montane forests, including pine-oak and evergreen cloud forests. Forest-edge-pasture gradients were characterised ...
Yannouleas, Constantine
2012-01-01T23:59:59.000Z
PHYSICAL REVIEW B 86, 165440 (2012) Graphene flakes with defective edge terminations: Universal (as a function of the magnetic field) are presented for trigonal graphene nanoflakes. The electronic spectra of trigonal graphene nanoflakes with reczag edge terminations exhibit certain unique
Ventilation efficiencies and thermal comfort results of a desk-edge-mounted task ventilation system
Faulkner, D.; Fisk, W.J.; Sullivan, D.P.; Lee, S.M.
2003-01-01T23:59:59.000Z
EDGE-MOUNTED TASK VENTILATION SYSTEM D Faulkner, WJ Fisk, DPDESK-EDGE-MOUNTED TASK VENTILATION SYSTEM D Faulkner * , WJcomfort of a task ventilation system with an air supply
Investigations of flow and film cooling on turbine blade edge regions
Yang, Huitao
2006-10-30T23:59:59.000Z
The inlet temperature of modern gas turbine engines has been increased to achieve higher thermal efficiency and increased output. The blade edge regions, including the blade tip, the leading edge, and the platform, are exposed to the most extreme...
Edge Localized Image Sharpening via Reassignment with Application to Computed Tomography
Bhashyam, Srikrishna
Edge Localized Image Sharpening via Reassignment with Application to Computed Tomography Timothy computed tomography. Practical implementations limit the amount of high frequency content. Keywords: Image enhancement, edge sharpening, computed tomography, wavelets, reassignment 1. INTRODUCTION
In Carpet Capitol of the World, Carpet Edging is Green Fuel ...
Broader source: Energy.gov (indexed) [DOE]
the World, Carpet Edging is Green Fuel In Carpet Capitol of the World, Carpet Edging is Green Fuel June 2, 2010 - 4:55pm Addthis Stephen Graff Former Writer & editor for Energy...
Statistical control and experimental design for edge bead reduction in laminating process
Fan, Huangjia (Francis Huangjia)
2010-01-01T23:59:59.000Z
Edge bead formation is a well-known phenomenon typically happening in the lamination due to the physics of this process. It causes the defect of high edge observed in the carton roll after the laminated carton sheets are ...
Simulating Ru L3-edge X-ray Absorption Spectroscopy with Time...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Ru L3-edge X-ray Absorption Spectroscopy with Time-Dependent Density Functional Theory: Model Complexes and Electron Simulating Ru L3-edge X-ray Absorption Spectroscopy with...
Edge-Induced Qubit Polarization in Systems with Ising Anyons
David J Clarke; Kirill Shtengel
2011-02-10T23:59:59.000Z
We investigate the proposed experimental setup for measuring the topological charge in a an Ising anyon system by means of Fabry-P\\'erot interferometry with a chiral edge state. We show that such an interferometer has the unintended but not necessarily unwelcome effect of stabilizing the state of the system being measured (i.e., a topological qubit). We show further that interactions between the edge mode and the localized bulk quasiparticles can have the effect of polarizing the qubit, stabilizing its state. We discuss the these results in the context of recent interferometer experiments in the 5/2 fractional quantum Hall state, where the first of these effects is small, but the second may be relevant to the observed phenomena.
A new metallographic procedure for edge retention of enclosed surfaces
Katz, O.M.
1994-08-01T23:59:59.000Z
Utilization of a low melting point, metallic alloy that on solidification has provided a reproducible means of preserving edges and accurately measuring deposits on surfaces mounted for metarographic study. In normal laboratory practice the electrically conducting mounting material generates no hazardous waste, needs no special equipment to prepare and is available commercially at a relatively reasonable price. Previous standard edge preservation techniques were found to be 90% inefficient from a time utilization view compared with the new procedure. This new mounting procedure has greatly improved the quality and efficiency of microstructural studies of all materials, especially those on the inside diameters of heat exchanger components. These studies have included reaction products, shallow creep cracks and deposits on tubing, for which the procedure has proved indispensable.
Nuclear Star Clusters in Edge-on Galaxies
Anil C. Seth; Julianne J. Dalcanton; Paul W. Hodge; Victor P. Debattista
2006-06-02T23:59:59.000Z
From observations of edge-on, late-type galaxies, we present morphological evidence that some nuclear star clusters have experienced in situ star formation. We find three nuclear clusters that, viewed from the edge-on perspective, have both a compact disk-like component and a spheroidal component. In each cluster, the disk components are closely aligned with the major axis of the host galaxy and have bluer colors than the spheroidal components. We spectroscopically verify that one of the observed multiple component clusters has multiple generations of stars. These observations lead us to suggest a formation mechanism for nuclear star clusters, in which stars episodically form in compact nuclear disks, and then lose angular momentum, eventually forming an older spheroid.
Interactions between Liquid-Wall Vapor and Edge Plasmas
Rognlien, T D; Rensink, M E
2000-05-25T23:59:59.000Z
The use of liquid walls for fusion reactors could help solve problems associated with material erosion from high plasma heat-loads and neutronic activation of structures. A key issue analyzed here is the influx of impurity ions to the core plasma from the vapor of liquid side-walls. Numerical 2D transport simulations are performed for a slab geometry which approximates the edge region of a reactor-size tokamak. Both lithium vapor (from Li or SnLi walls) and fluorine vapor (from Flibe walls) are considered for hydrogen edge-plasmas in the high- and low-recycling regimes. It is found that the minimum influx is from lithium with a low-recycling hydrogen plasma, and the maximum influx occurs for fluorine with a high-recycling hydrogen plasma.
Edge-states ferromagnetism of WS{sub 2} nanosheets
Huo, Nengjie; Li, Yan; Kang, Jun; Li, Renxiong; Xia, Qinglin; Li, Jingbo, E-mail: jbli@semi.ac.cn [State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P. O. Box 912, Beijing 100083 (China)
2014-05-19T23:59:59.000Z
The multilayer WS{sub 2} nanosheets prepared from WO{sub 3} nanowires exhibit strong ferromagnetic behavior with saturation magnetization (M{sub S}) of 0.0058?emu/g and coercive field (H{sub C}) of 92?Oe at room temperature. By decreasing the temperature down to 3?K the H{sub c} is increased up to 1115 Oe, revealing the existence of long-range magnetic ordering. Density functional theory spin-polarized calculations predict that strong ferromagnetic moments in WS{sub 2} nanosheets are attributed to the zigzag edge sulphur S and tungsten W atoms. Our findings also suggest that the WS{sub 2} nanosheets with a high density of edge spins could be used to fabricate spintronics devices, which are circuits utilizing the spin of the electron to process and store information.
Rimmed and edge thickened stodola shaped flywheel. [Patent application
Kulkarni, S.V.; Stone, R.G.
1980-09-24T23:59:59.000Z
A flywheel is described that is useful for energy storage in a hybrid vehicle automotive power system or in some stationary applications. The flywheel has a body composed of essentially planar isotropic high strength material. The flywheel body is enclosed by a rim of circumferentially wound fiber embedded in resin. The rim promotes flywheel safety and survivability. The flywheel has a truncated and edge thickened Stodola shape designed to optimize system mass and energy storage capability.
Aluminium K-Edge XANES Study of Mica Preiswerkite
Wu, Z.; Marcelli, A.; Cibin, G.; Mottana, A.; Della Ventura, G.; /SLAC, SSRl
2006-10-27T23:59:59.000Z
We present the Al K-edge XANES spectrum of synthetic mica with mixed fourfold coordinated and sixfold coordinated Al (preiswerkite). Experimental analysis and multiple scattering simulations of XANES spectra demonstrate that octahedral contributions may overlap the tetrahedral ones so that the lower energy structures in mixed coordination compounds may be associated to Al octahedral site. This unexpected behavior can be explained as due to a large local distortion of the Al octahedral site.
Characterization and Modification of Edge-Driven Instabilities in the DIII-D Tokamak
Ferron, J.R.; Lao, L.L.; Osborne, T.H.; Strait, E.J.; Turnbull, A.D.; Miller, R.L.; Taylor, T.S.; Doyle, E.J.; Rice, B.W.; Zhang, C.; Chen, L.; Baylor, L.R.; Murakami, M.; Wade, M.R.
1999-07-01T23:59:59.000Z
The character of edge localized modes (ELMs) and the height of the edge pressure pedestal in DIII-D tokamak H-mode discharges have been modified by varying the discharge shape (triangularity and squareness) and the safety factor, increasing the edge radiation, and injecting deuterium pellets. Changes in the ELM frequency and amplitude, and the magnitude of the edge pressure gradient, and changes in the calculated extent of the region of access to the ballooning mode second stability regime are observed.
The Cutting Edge of Fun: Making Work Play at the New American School
Sims, Christopher Otter
2012-01-01T23:59:59.000Z
cutting edge,” fun, “digital” school – an image that registered with his parents – and the more structural factors
Mair, Bernard A.
China Colombia Costa Rica Ecuador France Greece India Iraq Israel Japan Korea Kuwait Libya Qatar Russia
UCDSCULPTURE TRAIL Roebuck Road
trained with Michael Biggs. This work was the result of a Stone Symposium in the Dublin mountains in 1984
A knife-edge array field emission cathode
Lee, B.
1994-08-01T23:59:59.000Z
many cathode applications require a new type of cathode that is able to produce short pulsed electron beams at high emission current. Gated field emitter arrays of micrometer size are recognized as candidates to meet this need and have become the research focus of vacuum microelectronics. Existing fabrication methods produce emitters that are limited either in frequency response or in current emission. One reason is that the structure of these emitters are not sufficiently optimized. In this study, the author investigated the factors that affect the performance of field emitters. An optimum emitter structure, the knife-edge field emitter array, was developed from the analysis. Large field enhancement factor, large effective emission area, and small emitter capacitance are the advantages of the structure. The author next explored various options of fabricating the knife-edge emitter structure. He proposed a unique thin film process procedure and developed the fabrication techniques to build the emitters on (110) silicon wafers. Data from the initial cathode tests showed very low onset voltages and Fowler-Nordheim type emission. Emission simulation based on the fabricated emitter structure indicated that the knife-edge emitter arrays have the potential to produce high performance in modulation frequency and current emission. Several fabrication issues that await further development are discussed and possible solutions are suggested.
Theory of nitrogen doping of carbon nanoribbons: Edge effects
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Jiang, Jie; Turnbull, Joseph; Lu, Wenchang; Boguslawski, Piotr; Bernholc, J.
2012-01-01T23:59:59.000Z
Nitrogen doping of a carbon nanoribbon is profoundly affected by its one-dimensional character, symmetry, and interaction with edge states. Using state-of-the-art ab initio calculations, including hybrid exact-exchange density functional theory, we find that, for N-doped zigzag ribbons, the electronic properties are strongly dependent upon sublattice effects due to the non-equivalence of the two sublattices. For armchair ribbons, N-doping effects are different depending upon the ribbon family: for families 2 and 0, the N-induced levels are in the conduction band, while for family 1 the N levels are in the gap. In zigzag nanoribbons, nitrogen close to the edge is amore »deep center, while in armchair nanoribbons its behavior is close to an effective-mass-like donor with the ionization energy dependent on the value of the band gap. In chiral nanoribbons, we find strong dependence of the impurity level and formation energy upon the edge position of the dopant, while such site-specificity is not manifested in the magnitude of the magnetization.« less
Theory of nitrogen doping of carbon nanoribbons: Edge effects
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Jiang, Jie [North Carolina State Univ., Raleigh, NC (United States) and Yale Univ, New Haven, CT (United States); Turnbull, Joseph [North Carolina State Univ., Raleigh, NC (United States); Lu, Wenchang [North Carolina State Univ., Raleigh, NC (United States) and Oak Ridge National Lab., TN (United States); Boguslawski, Piotr [North Carolina State Univ., Raleigh, NC (United States) and Institute of Physics, Warsaw, and Bydgoszcz (Poland); Bernholc, J. [North Carolina State Univ., Raleigh, NC (United States) and Oak Ridge National Lab., TN (United States)
2012-01-05T23:59:59.000Z
Nitrogen doping of a carbon nanoribbon is profoundly affected by its one-dimensional character, symmetry, and interaction with edge states. Using state-of-the-art ab initio calculations, including hybrid exact-exchange density functional theory, we find that, for N-doped zigzag ribbons, the electronic properties are strongly dependent upon sublattice effects due to the non-equivalence of the two sublattices. For armchair ribbons, N-doping effects are different depending upon the ribbon family: for families 2 and 0, the N-induced levels are in the conduction band, while for family 1 the N levels are in the gap. In zigzag nanoribbons, nitrogen close to the edge is a deep center, while in armchair nanoribbons its behavior is close to an effective-mass-like donor with the ionization energy dependent on the value of the band gap. In chiral nanoribbons, we find strong dependence of the impurity level and formation energy upon the edge position of the dopant, while such site-specificity is not manifested in the magnitude of the magnetization.
Nakamura, Masanori [Department of Physics and Astronomy, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 (United States); Garofalo, David; Meier, David L., E-mail: nakamura@stsci.ed, E-mail: david.a.garofalo@jpl.nasa.go, E-mail: david.l.meier@jpl.nasa.go [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)
2010-10-01T23:59:59.000Z
This is the first in a series of papers that introduces a new paradigm for understanding the jet in M87: a collimated relativistic flow in which strong magnetic fields play a dominant dynamical role. Here, we focus on the flow downstream of HST-1-an essentially stationary flaring feature that ejects trails of superluminal components. We propose that these components are quad relativistic magnetohydrodynamic shock fronts (forward/reverse fast and slow modes) in a narrow jet with a helically twisted magnetic structure. And we demonstrate the properties of such shocks with simple one-dimensional numerical simulations. Quasi-periodic ejections of similar component trails may be responsible for the M87 jet substructures observed further downstream on 10{sup 2}-10{sup 3} pc scales. This new paradigm requires the assimilation of some new concepts into the astrophysical jet community, particularly the behavior of slow/fast-mode waves/shocks and of current-driven helical kink instabilities. However, the prospects of these ideas applying to a large number of other jet systems may make this worth the effort.
Relaxation of potential, flows, and density in the edge plasma of CASTOR tokamak
Boyer, Edmond
Relaxation of potential, flows, and density in the edge plasma of CASTOR tokamak M. Hron1 , V on the CASTOR tokamak. A biased electrode has been used to polarize the edge plasma. The edge plasma potential time in the range of 10 - 30 µs when the electrode biasing is turn off in the CASTOR tokamak
Linear calculations of edge current driven kink modes with BOUT++ code
Li, G. Q., E-mail: ligq@ipp.ac.cn; Xia, T. Y. [Institute of Plasma Physics, CAS, Hefei, Anhui 230031 (China); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Xu, X. Q. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Snyder, P. B.; Turnbull, A. D. [General Atomics, San Diego, California 92186 (United States); Ma, C. H.; Xi, P. W. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); FSC, School of Physics, Peking University, Beijing 100871 (China)
2014-10-15T23:59:59.000Z
This work extends previous BOUT++ work to systematically study the impact of edge current density on edge localized modes, and to benchmark with the GATO and ELITE codes. Using the CORSICA code, a set of equilibria was generated with different edge current densities by keeping total current and pressure profile fixed. Based on these equilibria, the effects of the edge current density on the MHD instabilities were studied with the 3-field BOUT++ code. For the linear calculations, with increasing edge current density, the dominant modes are changed from intermediate-n and high-n ballooning modes to low-n kink modes, and the linear growth rate becomes smaller. The edge current provides stabilizing effects on ballooning modes due to the increase of local shear at the outer mid-plane with the edge current. For edge kink modes, however, the edge current does not always provide a destabilizing effect; with increasing edge current, the linear growth rate first increases, and then decreases. In benchmark calculations for BOUT++ against the linear results with the GATO and ELITE codes, the vacuum model has important effects on the edge kink mode calculations. By setting a realistic density profile and Spitzer resistivity profile in the vacuum region, the resistivity was found to have a destabilizing effect on both the kink mode and on the ballooning mode. With diamagnetic effects included, the intermediate-n and high-n ballooning modes can be totally stabilized for finite edge current density.
The smallest k-regular h-edge-connected graphs without , Douglas B. West
West, Douglas B.
-regular graph with no cut-edge has a 1-factor. This has many generalizations. Showing that every kThe smallest k-regular h-edge-connected graphs without 1-factors John Ganci , Douglas B. West March-regular (k - 1)-edge-connected graph of even order has a 1-factor is a standard elementary exercise (#3
Gorini, Daniel
1994-01-01T23:59:59.000Z
The core of this investigation is based on the design of built form at the public urban river edge. It proposes the transformation of a portion of public park edge into public built edge. The Esplanade embankment at the ...
Tsutsui, Shigeyoshi
to PMBGAsPMBGAs inin permutationpermutation domainsdomains Edge Histogram Sampling Algorithm (EHBSA another approach toWe propose another approach to PMBGAsPMBGAs inin permutationpermutation domainsdomains
Strong transmission and reflection of edge modes in bounded photonic graphene
Ablowitz, Mark J
2015-01-01T23:59:59.000Z
The propagation of linear and nonlinear edge modes in bounded photonic honeycomb lattices formed by an array of rapidly varying helical waveguides is studied. These edge modes are found to exhibit strong transmission (reflection) around sharp corners when the dispersion relation is topologically nontrivial (trivial), and can also remain stationary. An asymptotic theory is developed that establishes the presence (absence) of edge states on all four sides, including in particular armchair edge states, in the topologically nontrivial (trivial) case. In the presence of topological protection, nonlinear edge solitons can persist over very long distances.
Giuseppe Congedo
2015-04-24T23:59:59.000Z
The measurement of frequency shifts for light beams exchanged between two test masses nearly in free fall is at the heart of gravitational wave detection. It is envisaged that the derivative of the frequency shift is in fact limited by differential forces acting on those test masses. We calculate the derivative of the frequency shift with a fully covariant, gauge-independent and coordinate-free method. This method is general and does not require a congruence of nearby beams' null geodesics as done in previous work. We show that the derivative of the parallel transport is the only means by which gravitational effects shows up in the frequency shift. This contribution is given as an integral of the Riemann tensor --the only physical observable of curvature-- along the beam's geodesic. The remaining contributions are: the difference of velocities, the difference of non-gravitational forces, and finally fictitious forces, either locally at the test masses or non-locally integrated along the beam's geodesic. As an application relevant to gravitational wave detection, we work out the frequency shift in the local Lorentz frame of nearby geodesics.
Spinning particles in vacuum space-times of different curvature types -- I
Semerák, O
2015-01-01T23:59:59.000Z
We consider the motion of spinning test particles with non-zero rest mass in the "pole-dipole" approximation, as described by the Mathisson--Papapetrou--Dixon (MPD) equations, and examine its properties in dependence on the spin supplementary condition added to close the system and on algebraic type of curvature. The MPD equation of motion is first decomposed in the orthonormal tetrad whose time-like vector is given by the four-velocity $V^\\mu$ fixing the spin condition (the "reference observer") and the first spatial vector by the corresponding spin $s^\\mu$; such MPD-equation projections do not contain the Weyl scalars $\\Psi_0$ and $\\Psi_4$ obtained in the related Newman--Penrose null tetrad. One natural option how to choose the remaining two spatial basis vectors, is shown to follow "intrinsically" whenever the reference observer $V^\\mu$ has been chosen; it is realizable if the particle's four-velocity and four-momentum are not parallel. In order to discuss the problem in dependence on space-time Petrov typ...
Observation of chiral edge states with neutral fermions in synthetic Hall ribbons
Mancini, M; Cappellini, G; Livi, L; Rider, M; Catani, J; Sias, C; Zoller, P; Inguscio, M; Dalmonte, M; Fallani, L
2015-01-01T23:59:59.000Z
Chiral edge states are a hallmark of quantum Hall physics. In electronic systems, they appear as a macroscopic consequence of the cyclotron orbits induced by a magnetic field, which are naturally truncated at the physical boundary of the sample. Here we report on the experimental realization of chiral edge states in a ribbon geometry with an ultracold gas of neutral fermions subjected to an artificial gauge field. By imaging individual sites along a synthetic dimension, we detect the existence of the edge states, investigate the onset of chirality as a function of the bulk-edge coupling, and observe the edge-cyclotron orbits induced during a quench dynamics. The realization of fermionic chiral edge states is a fundamental achievement, which opens the door towards experiments including edge state interferometry and the study of non-Abelian anyons in atomic systems.
Edge coating apparatus with movable roller applicator for solar cell substrates
Pavani, Luca; Abas, Emmanuel
2012-12-04T23:59:59.000Z
A non-contact edge coating apparatus includes an applicator for applying a coating material on an edge of a solar cell substrate and a control system configured to drive the applicator. The control system may drive the applicator along an axis to maintain a distance with an edge of the substrate as the substrate is rotated to have the edge coated with a coating material. The applicator may include a recessed portion into which the edge of the substrate is received for edge coating. For example, the applicator may be a roller with a groove. Coating material may be introduced into the groove for application onto the edge of the substrate. A variety of coating materials may be employed with the apparatus including hot melt ink and UV curable plating resist.
Observation of chiral edge states with neutral fermions in synthetic Hall ribbons
M. Mancini; G. Pagano; G. Cappellini; L. Livi; M. Rider; J. Catani; C. Sias; P. Zoller; M. Inguscio; M. Dalmonte; L. Fallani
2015-02-09T23:59:59.000Z
Chiral edge states are a hallmark of quantum Hall physics. In electronic systems, they appear as a macroscopic consequence of the cyclotron orbits induced by a magnetic field, which are naturally truncated at the physical boundary of the sample. Here we report on the experimental realization of chiral edge states in a ribbon geometry with an ultracold gas of neutral fermions subjected to an artificial gauge field. By imaging individual sites along a synthetic dimension, we detect the existence of the edge states, investigate the onset of chirality as a function of the bulk-edge coupling, and observe the edge-cyclotron orbits induced during a quench dynamics. The realization of fermionic chiral edge states is a fundamental achievement, which opens the door towards experiments including edge state interferometry and the study of non-Abelian anyons in atomic systems.
Feng, Guang [ORNL; Jiang, Deen [ORNL; Cummings, Peter T [ORNL
2012-01-01T23:59:59.000Z
Recent experiments have revealed that onion-like carbons (OLCs) offer high energy density and charging/discharging rates when used as the electrodes in supercapacitors. To understand the physical origin of this phenomenon, molecular dynamics simulations were performed for a room-temperature ionic liquid near idealized spherical OLCs with radii ranging from 0.356 to 1.223 nm. We find that the surface charge density increases almost linearly with the potential applied on electric double layers (EDLs) near OLCs. This leads to a nearly flat shape of the differential capacitance versus the potential, unlike the bell or camel shape observed on planar electrodes. Moreover, our simulations reveal that the capacitance of EDLs on OLCs increases with the curvature or as the OLC size decreases, in agreement with experimental observations. The curvature effect is explained by dominance of charge overscreening over a wide potential range and increased ion density per unit area of electrode surface as the OLC becomes smaller.
Luminescence from Edge Fracture in Shocked Lithium Fluoride Crystals
Turley, W. D. [NSTec; Stevens, G. D. [NSTec; Capelle, G. A. [NSTec; Grover, M. [NSTec; Holtkamp, D. B. [LANL; LaLone, B. M. [NSTec; Veeser, L. R. [NSTec, LANL
2013-04-01T23:59:59.000Z
Light emitted from a [100] lithium fluoride crystal was characterized under shock wave compression to 28GPa followed by complete stress release at the edges. The light was examined using time-gated optical spectrometry and imaging, time-resolved optical emission measurements, and hydrodynamic modeling. The shock arrival at the circumference of the crystal was delayed relative to the center so that the two regions could be studied at different times. The majority of the light emission originated when the shock waves released at the circumference of the crystal. Unlike previously reported results for shocked lithium fluoride, we found that the light spectrum is not strictly broad band, but has spectral lines associated with atomic lithium in addition to a broad band background. Also, the emission spectrum depends strongly on the gas surrounding the sample. Based on our observations, the line emission appears to be related to fracture of the lithium fluoride crystal from the shock wave releasing at the edges. Experimenters frequently utilize lithium fluoride crystals as transparent windows for observing shock compressed samples. Because of the experimental geometries used, the shock wave in such cases often reaches the circumference of the window at nearly the same moment as when it reaches the center of the sample-window interface. Light generated at the circumference could contaminate the measurement at the interface when this light scatters into the observed region. This background light may be reduced or avoided using experimental geometries which delay the arrival of the shock wave at the edges of the crystal.
Growing Cutting-edge X-ray Optics
Ray Conley
2013-07-17T23:59:59.000Z
Ever imagined that an Xbox controller could help open a window into a world spanning just one billionth of a meter? Brookhaven Lab's Ray Conley grows cutting-edge optics called multilayer Laue lenses (MLL) one atomic layer at a time to focus high-energy x-rays to within a single nanometer. To achieve this focusing feat, Ray uses a massive, custom-built atomic deposition device, an array of computers, and a trusty Xbox controller. These lenses will be deployed at the Lab's National Synchrotron Light Source II, due to begin shining super-bright light on pressing scientific puzzles in 2015
Reducing disorder in graphene nanoribbons by chemical edge modification
Dauber, J.; Terrés, B.; Volk, C.; Stampfer, C. [JARA-FIT and II. Institute of Physics, RWTH Aachen University, 52074 Aachen (Germany); Peter Grünberg Institute (PGI-8/9), Forschungszentrum Jülich, 52425 Jülich (Germany); Trellenkamp, S. [Peter Grünberg Institute (PGI-8/9), Forschungszentrum Jülich, 52425 Jülich (Germany)
2014-02-24T23:59:59.000Z
We present electronic transport measurements on etched graphene nanoribbons on silicon dioxide before and after a short hydrofluoric acid (HF) treatment. We report on changes in the transport properties, in particular, in terms of a decreasing transport gap and a reduced doping level after HF dipping. Interestingly, the effective energy gap is nearly unaffected by the HF treatment. Additional measurements on a graphene nanoribbon with lateral graphene gates support strong indications that the HF significantly modifies the edges of the investigated nanoribbons leading to a significantly reduced disorder potential in these graphene nanostructures.
Bulk-edge correspondence for two-dimensional topological insulators
G. M. Graf; M. Porta
2013-03-19T23:59:59.000Z
Topological insulators can be characterized alternatively in terms of bulk or edge properties. We prove the equivalence between the two descriptions for two-dimensional solids in the single-particle picture. We give a new formulation of the $\\mathbb{Z}_{2}$-invariant, which allows for a bulk index not relying on a (two-dimensional) Brillouin zone. When available though, that index is shown to agree with known formulations. The method also applies to integer quantum Hall systems. We discuss a further variant of the correspondence, based on scattering theory.
Low-temperature random matrix theory at the soft edge
Edelman, Alan [Department of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Persson, Per-Olof [Department of Mathematics, University of California, Berkeley, California 94720 (United States); Sutton, Brian D. [Department of Mathematics, Randolph-Macon College, Ashland, Virginia 23005 (United States)
2014-06-15T23:59:59.000Z
“Low temperature” random matrix theory is the study of random eigenvalues as energy is removed. In standard notation, ? is identified with inverse temperature, and low temperatures are achieved through the limit ? ? ?. In this paper, we derive statistics for low-temperature random matrices at the “soft edge,” which describes the extreme eigenvalues for many random matrix distributions. Specifically, new asymptotics are found for the expected value and standard deviation of the general-? Tracy-Widom distribution. The new techniques utilize beta ensembles, stochastic differential operators, and Riccati diffusions. The asymptotics fit known high-temperature statistics curiously well and contribute to the larger program of general-? random matrix theory.
SolarEdge Technologies Inc | Open Energy Information
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Edge Radial Electric Field on Alcator C-Mod
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The Bleeding 'Edge' of Fusion Research | Princeton Plasma Physics Lab
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River Edge, New Jersey: Energy Resources | Open Energy Information
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Hughes, Jerry
Neutral-plasma interactions are expected to have a significant influence on edge plasma conditions in the edge region of a tokamak plasma, and thus on global plasma confinement. In particular, the particle source from ionization should be considered in the study of plasma transport within the H-mode pedestal
Igor Romanovsky; Constantine Yannouleas; Uzi Landman
2010-12-27T23:59:59.000Z
Dirac electrons in finite graphene samples with zigzag edges under high magnetic fields (in the regime of Landau-level formation) are investigated with regard to their bulk-type and edge-type character. We employ tight-binding calculations on finite graphene flakes (with various shapes) to determine the sublattice components of the electron density in conjunction with analytic expressions (via the parabolic cylinder functions) of the relativistic-electron spinors that solve the continuous Dirac-Weyl equation for a semi-infinite graphene plane. Away from the sample edge, the higher Landau levels are found to comprise exclusively electrons of bulk-type character (for both sublattices); near the sample edge, these electrons are described by edge-type states similar to those familiar from the theory of the integer quantum Hall effect for nonrelativistic electrons. In contrast, the lowest (zero) Landau level contains relativistic Dirac electrons of a mixed bulk-edge character without an analog in the nonrelativistic case. It is shown that such mixed bulk-edge states maintain also in the case of a square flake with combined zigzag and armchair edges. Implications for the many-body correlated-electron behavior (relating to the fractional quantum Hall effect) in finite graphene samples are discussed.
Chowdhury, Debashree, E-mail: debashreephys@gmail.com; Basu, B., E-mail: sribbasu@gmail.com
2013-02-15T23:59:59.000Z
We have studied the spin dependent force and the associated momentum space Berry curvature in an accelerating system. The results are derived by taking into consideration the non-relativistic limit of a generally covariant Dirac equation with an electromagnetic field present, where the methodology of the Foldy-Wouthuysen transformation is applied to achieve the non-relativistic limit. Spin currents appear due to the combined action of the external electric field, the crystal field and the induced inertial electric field via the total effective spin-orbit interaction. In an accelerating frame, the crucial role of momentum space Berry curvature in the spin dynamics has also been addressed from the perspective of spin Hall conductivity. For time dependent acceleration, the expression for the spin polarization has been derived. - Highlights: Black-Right-Pointing-Pointer We study the effect of acceleration on the Dirac electron in the presence of an electromagnetic field, where the acceleration induces an electric field. Black-Right-Pointing-Pointer Spin currents appear due to the total effective electric field via the total spin-orbit interaction. Black-Right-Pointing-Pointer We derive the expression for the spin dependent force and the spin Hall current, which is zero for a particular acceleration. Black-Right-Pointing-Pointer The role of the momentum space Berry curvature in an accelerating system is discussed. Black-Right-Pointing-Pointer An expression for the spin polarization for time dependent acceleration is derived.
Sujan Sengupta
1998-01-29T23:59:59.000Z
The ohmic decay of magnetic fields confined within the crust of neutron stars is considered by incorporating both the effect of neutron star cooling and the effect of space-time curvature produced by the intense gravitational field of the star. For this purpose a stationary and static gravitational field has been considered with the standard as well as the accelerated cooling models of neutron stars. It is shown that general relativistic effect reduces the magnetic field decay rate substantially. At the late stage of evolution when the field decay is mainly determined by the impurity-electron scattering, the effect of space-time curvature suppresses the role of the impurity content significantly and reduces the decay rate by more than an order of magnitude. Even with a high impurity content the decay rate is too low to be of observational interest if the accelerated cooling model along with the effect of space-time curvature is taken into account. It is, therefore, pointed out that if a decrease in the magnetic field strength by more than two orders of magnitude from its initial value is detected by observation then the existence of quark in the core of the neutron star would possibly be ruled out.
Yang, B. J.; Souri, H.; Lee, H. K., E-mail: leeh@kaist.ac.kr [Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Kim, Sunghwan; Ryu, Seunghwa [Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)
2014-07-21T23:59:59.000Z
In this study, analytical expressions are introduced to provide a better understanding of carbon nanotubes (CNTs) curvature on the overall behavior of nanocomposites. The curviness of CNT is modeled as the wave geometries, and the transformed physical characteristics are applied to micromechanical framework. Since five independent elastic constants of CNTs are essential to derive the waviness effect, atomistic molecular statics simulations with varying nanotube radii are conducted. Influences of CNT curviness on the effective stiffness of the nanocomposites are analyzed, noting that the curvature effect is significantly influential on the effective stiffness of the nanocomposites, and it may improve or reduce the reinforcing effect depending on the orientation of CNTs. In addition, the predictions are compared with experimental data of the CNT-reinforced nanocomposites to assess the reliability of the proposed method. The developed constitutive model is expected to be used to determine the volume concentration of the reinforcing CNTs and mechanical responses of CNT-reinforced composites under various CNT curvature, radius, and orientation conditions.
Turgeon, C.M.
1991-02-01T23:59:59.000Z
The need to reduce our states dependence on land fills resulted in a unique cooperative venture by three state agencies. A partnership was forged between the Minnesota Pollution Control Agency (MPCA), the Minnesota Department of Natural Resources (DNR) and the Minnesota Department of Transportation (Mn/DOT) to investigate the use of recycled tire rubber and processed asphalt shingle scrap. The result is a two mile section of the Willard Munger Recreational Trail in St. Paul constructed with asphalt paving mixtures which contain varying percentages of recycled tire rubber and shingle scrap. Conventional mixing and paving equipment was utilized for construction. The application appears to be a viable alternative to landfilling these materials. However, costs for the mixtures containing rubber increased from 35% to 50% over the cost of the conventional mixture. Since the use of shingle scrap was negotiated by the private companies involved, no comparable cost data is available.
Framework Application for Core Edge Transport Simulation (FACETS)
Krasheninnikov, Sergei; Pigarov, Alexander
2011-10-15T23:59:59.000Z
The FACETS (Framework Application for Core-Edge Transport Simulations) project of Scientific Discovery through Advanced Computing (SciDAC) Program was aimed at providing a high-fidelity whole-tokamak modeling for the U.S. magnetic fusion energy program and ITER through coupling separate components for each of the core region, edge region, and wall, with realistic plasma particles and power sources and turbulent transport simulation. The project also aimed at developing advanced numerical algorithms, efficient implicit coupling methods, and software tools utilizing the leadership class computing facilities under Advanced Scientific Computing Research (ASCR). The FACETS project was conducted by a multi-discipline, multi-institutional teams, the Lead PI was J.R. Cary (Tech-X Corp.). In the FACETS project, the Applied Plasma Theory Group at the MAE Department of UCSD developed the Wall and Plasma-Surface Interaction (WALLPSI) module, performed its validation against experimental data, and integrated it into the developed framework. WALLPSI is a one-dimensional, coarse grained, reaction/advection/diffusion code applied to each material boundary cell in the common modeling domain for a tokamak. It incorporates an advanced model for plasma particle transport and retention in the solid matter of plasma facing components, simulation of plasma heat power load handling, calculation of erosion/deposition, and simulation of synergistic effects in strong plasma-wall coupling.
Pappu, Kameswara Rao
1993-01-01T23:59:59.000Z
stresses. The theory also describes the straight wake as a special case, for which the radius of curvature approaches infinity. To show general validity of theory, it has been compared with experimental measurements available from Turbomachinery...
Using the Comoving Maximum of the Galaxy Power Spectrum to Measure Cosmological Curvature
Tom Broadhurst; Andrew H. Jaffe
1999-04-26T23:59:59.000Z
The large-scale maximum at k~0.05 identified in the power-spectrum of galaxy fluctuations provides a co-moving scale for measuring cosmological curvature. In shallow 3D surveys the peak is broad, but appears to be well resolved in 1D, at ~130 Mpc (k=0.048), comprising evenly spaced peaks and troughs. Surprisingly similar behaviour is evident at z=3 in the distribution of Lyman-break galaxies, for which we find a 5 sigma excess of pairs separated by Delta z=0.22pm0.02, equivalent to 85Mpc for Omega=1, increasing to 170 Mpc for Omega=0, with a number density contrast of 30% averaged over 5 independent fields. The combination, 3.2\\Omega_m -\\Omega_{\\Lambda}=0.7, matches the local scale of 130 Mpc, i.e. Omega=0.2\\pm0.1 or Omega_{m}=0.4\\pm0.1 for the matter-dominated and flat models respectively, with an uncertainty given by the width of the excess correlation. The consistency here of the flat model with SNIa based claims is encouraging, but overshadowed by the high degree of coherence observed in 1D compared with conventional Gaussian models of structure formation. The appearance of this scale at high redshift and its local prominence in the distribution of Abell clusters lends support to claims that the high-z `spikes' represent young clusters. Finally we show that a spike in the primordial power spectrum of delta\\rho/\\rho=0.3 at k=0.05 has little effect on the CMB, except to exaggerate the first Doppler peak in flat matter-dominated models, consistent with recent observations. \\\\effect on the CMB, except to exaggerate the first Doppler peak in flat matter-dominated models, consistent with recent observations.
Curvature-induced D-band Raman scattering in folded graphene This article has been downloaded from.1088/0953-8984/22/33/334205 Curvature-induced D-band Raman scattering in folded graphene* Awnish K Gupta1 , Cristiano Nisoli2 , Paul E Micro-Raman scattering from folds in single-layer graphene sheets finds a D-band at the fold for both
Pardivala, Darayus Noshir
1991-01-01T23:59:59.000Z
ESTABLISHMENT OF A RESEARCH FACILITY FOR INVESTIGATING THE EFFECTS OF UNSTEADY INLET FLOW) PRESSURE GRADIENT AND CURVATURE ON BOUNDARY LAYER DEVELOPMENT) %'AKE DEVELOPMENT AND HEAT TRANSFER A Thesis by DARAYUS NOSHIR PARDIVALA Submitted... THE EFFECTS OF UNSTEADY INLET FLOW, PRESSURE GRADIENT AND CURVATURE ON BOUNDARY LAYER DEVELOPMENT, WAKE DEVELOPMENT AND HEAT TRANSFER A Thesis by DARAYUS NOSHIR PARDIVALA Approved as to style and content by: Taher Schobeiri (Chair of Committee) Gerald...
Srivastava, S K
2008-01-01T23:59:59.000Z
Here, cosmology of the late and future universe is obtained from $f(R)$-gravity with non-linear curvature terms $R^2$ and $R^3$ ($R$ being the Ricci scalar curvature). It is different from $f(R)$-dark enrgy models, where non-linear curvature terms are taken as gravitational alternative of dark energy. In the present model, neither linear nor no-linear curvature terms are taken as dark energy. Rather, dark energy terms are induced by curvature terms in the Friedmann equation derived from $f(R)$-gravitational equations. It has advantage over $f(R)$- dark energy models in the sense that the present model satisfies WMAP results and expands as $\\sim t^{2/3}$ during matter-dominance. So, it does not have problems due to which $f(R)$-dark energy models are criticized. Curvature-induced dark energy, obtained here, mimics phantom. Different phases of this model, including acceleration and deceleration during phantom phase, are investigated here.It is found that expansion of the universe will stop at the age $(3.87 t_0...
Simultaneous laser cutting and welding of metal foil to edge of a plate
Pernicka, John C. (Fort Collins, CO); Benson, David K. (Golden, CO); Tracy, C. Edwin (Golden, CO)
1996-01-01T23:59:59.000Z
A method of welding an ultra-thin foil to the edge of a thicker sheet to form a vacuum insulation panel comprising the steps of providing an ultra-thin foil having a thickness less than 0.002, providing a top plate having an edge and a bottom plate having an edge, clamping the foil to the edge of the plate wherein the clamps act as heat sinks to distribute heat through the foil, providing a laser, moving the laser relative to the foil and the plate edges to form overlapping weld beads to weld the foil to the plate edges while simultaneously cutting the foil along the weld line formed by the overlapping beads.
Simultaneous laser cutting and welding of metal foil to edge of a plate
Pernicka, J.C.; Benson, D.K.; Tracy, C.E.
1996-03-19T23:59:59.000Z
A method is described for welding an ultra-thin foil to the edge of a thicker sheet to form a vacuum insulation panel comprising the steps of providing an ultra-thin foil having a thickness less than 0.002, providing a top plate having an edge and a bottom plate having an edge, clamping the foil to the edge of the plate wherein the clamps act as heat sinks to distribute heat through the foil, providing a laser, moving the laser relative to the foil and the plate edges to form overlapping weld beads to weld the foil to the plate edges while simultaneously cutting the foil along the weld line formed by the overlapping beads. 7 figs.
Effect of Deuterium Gas Puff On The Edge Plasma In NSTX
Zweben, S. J.
2014-02-20T23:59:59.000Z
This paper describes a detailed examination of the effects of a relatively small pulsed deuterium gas puff on the edge plasma and edge turbulence in NSTX. This gas puff caused little or no change in the line-averaged plasma density or total stored energy, or in the edge density and electron temperature up to the time of the peak of the gas puff. The radial profile of the D? light emission and the edge turbulence within this gas puff did not vary significantly over its rise and fall, implying that these gas puffs did not significantly perturb the local edge plasma or edge turbulence. These measurements are compared with modeling by DEGAS 2, UEDGE, and with simplified estimates for the expected effects of this gas puff.
Gain media edge treatment to suppress amplified spontaneous emission in a high power laser
Hackel, Lloyd A. (Livermore, CA); Soules, Thomas F. (Livermore, CA); Fochs, Scott N. (Livermore, CA); Rotter, Mark D. (San Ramon, CA); Letts, Stephan A. (San Ramon, CA)
2011-02-22T23:59:59.000Z
A novel method and apparatus for suppressing ASE and/or parasitic oscillation modes in a laser is introduced. By roughening one or more peripheral edges of a solid-state crystal or ceramic laser gain media and by bonding such edges to a predetermined electromagnetic absorbing material arranged adjacent to the entire outer surface of the peripheral edges of the roughened laser gain media, ASE, parasitic oscillation modes and/or residual pump energy can be effectively suppressed.
Gain media edge treatment to suppress amplified spontaneous emission in a high power laser
Hackel, Lloyd A. (Livermore, CA); Soules, Thomas F. (Livermore, CA); Fochs, Scott N. (Livermore, CA); Rotter, Mark D. (San Ramon, CA); Letts, Stephan A. (San Ramon, CA)
2008-12-09T23:59:59.000Z
A novel method and apparatus for suppressing ASE and parasitic oscillation modes in a high average power laser is introduced. By roughening one or more peripheral edges of a solid-state crystal or ceramic laser gain media and by bonding such edges using a substantially high index bonding elastomer or epoxy to a predetermined electromagnetic absorbing arranged adjacent to the entire outer surface of the peripheral edges of the roughened laser gain media, ASE and parasitic oscillation modes can be effectively suppressed.
Portable X-Ray, K-Edge Heavy Metal Detector
Fricke, V.
1999-10-25T23:59:59.000Z
The X-Ray, K-Edge Heavy Metal Detection System was designed and built by Ames Laboratory and the Center for Nondestructive Evaluation at Iowa State University. The system uses a C-frame inspection head with an X-ray tube mounted on one side of the frame and an imaging unit and a high purity germanium detector on the other side. the inspection head is portable and can be easily positioned around ventilation ducts and pipes up to 36 inches in diameter. Wide angle and narrow beam X-ray shots are used to identify the type of holdup material and the amount of the contaminant. Precise assay data can be obtained within minutes of the interrogation. A profile of the containerized holdup material and a permanent record of the measurement are immediately available.
Conductance matrix of multiterminal semiconductor devices with edge channels
Danilovskii, E. Yu., E-mail: danilovskii@mail.ioffe.ru; Bagraev, N. T. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)
2014-12-15T23:59:59.000Z
A method for determining the conductance matrix of multiterminal semiconductor structures with edge channels is proposed. The method is based on the solution of a system of linear algebraic equations based on Kirchhoff equations, made up of potential differences U{sub ij} measured at stabilized currents I{sub kl}, where i, j, k, l are terminal numbers. The matrix obtained by solving the system of equations completely describes the structure under study, reflecting its configuration and homogeneity. This method can find wide application when using the known Landauer-Buttiker formalism to analyze carrier transport in the quantum Hall effect and quantum spin Hall effect modes. Within the proposed method, the contribution of the contact area resistances R{sub c} to the formation of conductance matrix elements is taken into account. The possibilities of practical application of the results obtained in developing analog cryptographic devices are considered.
Center for Plasma Edge Simulation (CPES): Final Technical Report
Cummings, Julian C.
2013-02-19T23:59:59.000Z
The Center for Plasma Edge Simulation (CPES) project was a multi-institutional research effort funded jointly by the Office of Advanced Scientific Computing Research (OASCR) and the Office of Fusion Energy Sciences (OFES) within the Department of EnergyĂ?Â˘Ă?Â?Ă?Â?s Office of Science. The effort was led by our Principal Investigator, CS Chang, at the Courant Institute for Mathematical Sciences at New York University. The Center included participants from Oak Ridge National Laboratory, Princeton Plasma Physics Laboratory, Lawrence Berkeley National Laboratory, California Institute of Technology, Columbia University, Lehigh University, Rutgers University, University of Colorado, Massachusetts Institute of Technology, University of California at Davis, University of California at Irvine, North Carolina State University, and Georgia Institute of Technology. This report concerns the work performed by Dr. Julian C. Cummings, who was the institutional Principal Investigator for the CPES project at Caltech.
Capacitance of edge plane of pyrolytic graphite in acetonitrile solutions
Minick, S.K.; Ishida, Takanobu
1991-05-01T23:59:59.000Z
The capacitance of the edge plane of pyrolytic graphite electrodes, in acetonitrile solutions, is measured by recording the current response to an applied triangular voltage sweep; TVS, and then fitting the current response with an appropriate function, (via a set of adjustable parameters). The pretreatment of the electrodes, the supporting electrolyte concentration used, and the frequency of the input TVS, were all found to affect the measured capacitance. In these experiments, a background current was also seen and the shape of the current output for the TVS; the charging/discharging curve, is shown to correlate with the magnitude of this background current. In addition, the size of the background current was found to have some dependence on the type of electrode pretreatment procedure used. 60 refs., 49 figs., 3 tabs.
TCAT to Receive Ithaca's First 'Cutting-Edge' Fuel Cell Bus ...
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Archived News Stories Latest News TCAT to Receive Ithaca's First 'Cutting-Edge' Fuel Cell Bus 2 Cornellians receive Distinguished Scholar Award Versatile polymer film...
Ventilation efficiencies of a desk-edge-mounted task ventilation system
Faulkner, David; Fisk, William J.; Sullivan, Douglas P.; Lee, Seung Min
2002-01-01T23:59:59.000Z
DESK-EDGE-MOUNTED TASK VENTILATION SYSTEM D Faulkner * , WJthe effectiveness of a task ventilation system with an airthe desk. The task ventilation system provided outside air,
Risk of damaging the wires by edges of laser drilled holes in the end plugs
Staude, A; Trefzger, T M
1998-01-01T23:59:59.000Z
No sign of damage to the wire by edges of the laser drilled hole has been seen, based on a sample of four end plugs.
S. K. Srivastava
2008-02-07T23:59:59.000Z
Here, cosmology of the late and future universe is obtained from $f(R)$-gravity with non-linear curvature terms $R^2$ and $R^3$ ($R$ being the Ricci scalar curvature). It is different from $f(R)$-dark enrgy models, where non-linear curvature terms are taken as gravitational alternative of dark energy. In the present model, neither linear nor no-linear curvature terms are taken as dark energy. Rather, dark energy terms are induced by curvature terms in the Friedmann equation derived from $f(R)$-gravitational equations. It has advantage over $f(R)$- dark energy models in the sense that the present model satisfies WMAP results and expands as $\\sim t^{2/3}$ during matter-dominance. So, it does not have problems due to which $f(R)$-dark energy models are criticized. Curvature-induced dark energy, obtained here, mimics phantom. Different phases of this model, including acceleration and deceleration during phantom phase, are investigated here.It is found that expansion of the universe will stop at the age $(3.87 t_0 + 694.4 {\\rm kyr})$ ($t_0$ being the present age of the universe) and after this epoch, it will contract and collapse by the time $(336.87 t_0 + 694.4 {\\rm kyr})$. Further,it is shown that universe will escape predicted collapse (obtained using classical mechanics) on making quantum gravity corrections relevant near collapse time due to extremely high energy density and large curvature analogous to the state of very early universe. Interestingly, cosmological constant is also induced here, which is very small in classical domain, but very high in quantum domain.
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\
RECENT EXPERIMENTAL STUDIES OF EDGE AND INTERNAL TRANSPORT BARRIERS IN THE DIII-D TOKAMAK
P. GOHIL; L.R. BAYLOR; K.H. BURRELL; T.A. CASPER; E.J. DOYLE; C.M. GREENFIELD; T.C. JERNIGAN; J.E. KINSEY; C.J LASNIER; R.A. MOYER; M. MURAKAMI; T.L. RHODES; D.L. RUDAKOV; G.M. STAEBLER; G. WANG; J.G. WATKINS; W.P. WEST; L.ZENG
2002-08-01T23:59:59.000Z
Results from recent experiments on the DIII-D tokamak have revealed many important details on transport barriers at the plasma edge and in the plasma core. These experiments include: (a) the formation of the H-mode edge barrier directly by pellet injection; (b) the formation of a quiescent H-mode edge barrier (QH-mode) which is free from edge localized modes (ELMs), but which still exhibits good density and radiative power control; (c) the formation of multiple transport barriers, such as the quiescent double barrier (QDB) which combines a internal transport barrier with the quiescent H-mode edge barrier. Results from the pellet-induced H-mode experiments indicate that: (a) the edge temperature (electron or ion) is not a critical parameter for the formation of the H-mode barrier, (b) pellet injection leads to an increased gradient in the radial electric field, E{sub r}, at the plasma edge; (c) the experimentally determined edge parameters at barrier transition are well below the predictions of several theories on the formation of the H-mode barrier, (d) pellet injection can lower the threshold power required to form the H-mode barrier. The quiescent H-mode barrier exhibits good density control as the result of continuous magnetohydrodynamic (MHD) activity at the plasma edge called the edge harmonic oscillation (EHO). The EHO enhances the edge particle transport while maintaining a good energy transport barrier. The ability to produce multiple barriers in the QDB regime has led to long duration, high performance plasmas with {beta}{sub NH{sub 89}} values of 7 for up to 10 times the confinement time. Density profile control in the plasma core of QDB plasmas has been demonstrated using on-axis ECH.
aeroacoustics volume 9 number 3 2010 pages 273305 273 Extensions and limitations of analytical
Paris-Sud XI, Université de
technologies, such as cooling fans, wind turbines and turbofan engine blade rows. However meeting this need generated due to the formation of a coherent vortex shedding in the near wake of a thick trailing edge as sound at a trailing edge (trailing-edge noise), and the vortex shedding in the near wake of a blunt
Construction of $3\\otimes 3$ entangled edge states with positive partial transposes
Kil-Chan Ha; Seung-Hyeok Kye
2005-09-13T23:59:59.000Z
We construct a class of $3\\otimes 3$ entangled edge states with positive partial transposes using indecomposable positive linear maps. This class contains several new types of entangled edge states with respect to the range dimensions of themselves and their partial transposes.
MODELING OF STOCHASTIC MAGNETIC FLUX LOSS FROM THE EDGE OF A POOIDALLY DIVERTED TOKAMAK
EVANS, TE,; MOYER, RA; MONAT, P
2002-06-01T23:59:59.000Z
OAK A271 MODELING OF STOCHASTIC MAGNETIC FLUX LOSS FROM THE EDGE OF A POOIDALLY DIVERTED TOKAMAK. A field line integration code is used to study the loss of edge poloidal magnetic flux due to stochastic magnetic fields produced by an error field correction coil (C-coil) in DIII-D for various plasma shapes, coil currents and edge magnetic shear profiles. The authors find that the boundary of a diverted tokamak is more sensitive to stochastic flux loss than a nondiverted tokamak. The C-coil has been used to produce a stochastic layer in an ohmic diverted discharge with characteristics similar to those seen in stochastic boundary experiments in circular limiter ohmic plasmas, including: (1) an overall increase in recycling, (2) a broadening of the recycling profile at the divertor, and (3) a flattening of the boundary profiles over the extent of the stochastic layer predicted by the field line integration code. Profile flattening consistent with field line integration results is also seen in some high performance discharges with edge transport barriers. The prediction of a significant edge stochastic layer even in discharges with high performance and edge radial transport barriers indicates that either the self-consistent plasma response heals the stochastic layer or that edge stochastic layers are compatible with edge radial transport barriers.
Diamond, Richard
Over the Energy Edge: Results from a Seven Year New Commercial Buildings Research and Demonstration is that the actual, installed energy-efficiency measures and building characteristics changed from the design practice rather than assumptions based on the regional building code. For example, the Energy Edge small
The Zak phase and the existence of edge states in graphene
P. Delplace; D. Ullmo; G. Montambaux
2011-09-21T23:59:59.000Z
We develop a method to predict the existence of edge states in graphene ribbons for a large class of boundaries. This approach is based on the bulk-edge correspondence between the quantized value of the Zak phase Z(k), which is a Berry phase across an appropriately chosen one-dimensional Brillouin zone, and the existence of a localized state of momentum k at the boundary of the ribbon. This bulk-edge correspondence is rigorously demonstrated for a one dimensional toy model as well as for graphene ribbons with zigzag edges. The range of k for which edge states exist in a graphene ribbon is then calculated for arbitrary orientations of the edges. Finally, we show that the introduction of an anisotropy leads to a topological transition in terms of the Zak phase, which modifies the localization properties at the edges. Our approach gives a new geometrical understanding of edge states, it con?firms and generalizes the results of several previous works.
Kinetic Simulations of Retarding-Field Analyzer Measurements in Tokamak Edge Plasmas
Kinetic Simulations of Retarding-Field Analyzer Measurements in Tokamak Edge Plasmas Fabrice of probe measurements in tokamaks, particularly those obtained from Retarding-Field-Analyzers (RFAs) [1]. This type of probe provides an integral of the ion velocity distribution in tokamak edge plasmas, which
Edge ion heating by launched high harmonic fast waves in the National Spherical Torus Experiment
Biewer, Theodore
Edge ion heating by launched high harmonic fast waves in the National Spherical Torus Experiment T al., Fusion Technology 30, 1337 (1996)] measures the velocity distribution of ions in the plasma edge power High Harmonic Fast Wave (HHFW) rf heating in helium plasmas, with the poloidal ion temperature
Low Reynolds Number Flow Dynamics of a Thin Airfoil with an Actuated Leading Edge
Apte, Sourabh V.
alters the leading edge boundary-layer and vortex shedding and increases the mean lift-to-drag ratio Engineering, Oregon State University, Corvallis, OR 97331 Use of oscillatory actuation of the leading edge boundary problem on a fixed background mesh. The flow solver is three-dimensional, parallel, second
ACQUISITION AND RECONSTRUCTION OF BRAIN TISSUE USING KNIFE-EDGE SCANNING MICROSCOPY
Keyser, John
ACQUISITION AND RECONSTRUCTION OF BRAIN TISSUE USING KNIFE- EDGE SCANNING MICROSCOPY A Thesis Science #12;ACQUISITION AND RECONSTRUCTION OF BRAIN TISSUE USING KNIFE- EDGE SCANNING MICROSCOPY A Thesis) ______________________________ ______________________________ Ergun Akleman Valerie Taylor (Member) (Head of Department) December 2003 Major Subject: Computer Science
Enumerating the edge-colourings of a regular graph Stephane Bessy and Frederic Havet
Paris-Sud XI, Université de
Enumerating the edge-colourings of a regular graph St´ephane Bessy and Fr´ed´eric Havet Assistant and Combinatorics Deparment of Applied Mathematics, National Sun Yat-sen University, Kaohsiung, Taiwan. S. Bessy. Bessy and F.Havet () Enumerating the edge-colourings WGTC, Kaohsiung, 2012 2 / 41 lirmm-00811571,version
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 Ronnĺs 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
Disorder-induced mobility edges and heat flow control in anharmonic acoustic chains
Flach, Sergej
in cutting-edge fields of research from across the whole of physics. Each compilation is led by its own CoOFFPRINT Disorder-induced mobility edges and heat flow control in anharmonic acoustic chains M acceptance decisions 1 Impact Factor Â The 2009 Impact Factor increased by 31% to 2.893; your work
We are actively engaged in cutting-edge research spanning many diverse
ProdiĂ¦, Aleksandar
robotics and human factors to bioengineering and sustainability, our researchers are on the cutting edgeWe are actively engaged in cutting- edge research spanning many diverse specialties. As part and Design Â» Biomedical Engineering Â» Energy and Environmental Engineering Â» Human Factors
PSFC/JA-06-36 Edge profile stiffness and insensitivity of the density
Hughes, Jerry
of edge temperature and density pedestals, which are associated with edge transport barrier (ETB on density gradient scale lengths in the ETB and a relatively weak impact on the height of the density pedestal, even during aggressive deuterium puffing. Strong screening of neutrals in the ETB are observed
A. Gadomski; J. M. Rubi
2003-02-06T23:59:59.000Z
Matter agglomeration mesoscopic phenomena of irreversible type are well described by nonequilibrium thermodynamics formalism. The description assumes that the thermodynamic (internal) state variables are in local equilibrium, and uses the well known flux-force relations, with the Onsager coefficients involved, ending eventually up at a local conservation law of Fokker-Planck type. One of central problems arising when applying it to the matter agglomeration phenomena, quite generally termed nucleation-and-growth process, appears to be some physically accepted identification of entropic barriers, or factors impeding growth. In this paper, we wish to propose certain geometric-kinetic obstacles as serious candidates for the so-called entropic barriers. Within the framework of the thermodynamic formalism offered they are always associated with a suitable choice of a physical potential governing the system. It turns out that a certain choice of the potential of Coulomb (or, gravitational) type leads to emphasizing the role of the Gaussian curvature while another choice in a form of the logaritmic physical potential results unavoidably in a pronounced role of the mean curvature. The whole reasoning has been tested succesfully on a statistical-mechanical polycris- talline evolution model introduced some years ago for physical-metalurgical purposes, and modified for a use in biophysical soft-matter agglomerations.
Chevron beam dump for ITER edge Thomson scattering system
Yatsuka, E.; Hatae, T.; Bassan, M.; Itami, K. [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan)] [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan); Vayakis, G. [ITER Organization, 13115 St Paul Lez Durance Cedex (France)] [ITER Organization, 13115 St Paul Lez Durance Cedex (France)
2013-10-15T23:59:59.000Z
This paper contains the design of the beam dump for the ITER edge Thomson scattering system and mainly concerns its lifetime under the harsh thermal and electromagnetic loads as well as tight space allocation. The lifetime was estimated from the multi-pulse laser-induced damage threshold. In order to extend its lifetime, the structure of the beam dump was optimized. A number of bent sheets aligned parallel in the beam dump form a shape called a chevron which enables it to avoid the concentration of the incident laser pulse energy. The chevron beam dump is expected to withstand thermal loads due to nuclear heating, radiation from the plasma, and numerous incident laser pulses throughout the entire ITER project with a reasonable margin for the peak factor of the beam profile. Structural analysis was also carried out in case of electromagnetic loads during a disruption. Moreover, detailed issues for more accurate assessments of the beam dump's lifetime are clarified. Variation of the bi-directional reflection distribution function (BRDF) due to erosion by or contamination of neutral particles derived from the plasma is one of the most critical issues that needs to be resolved. In this paper, the BRDF was assumed, and the total amount of stray light and the absorbed laser energy profile on the beam dump were evaluated.
Edge Universality for a Class of Repulsive Particle Systems
Thomas Kriecherbauer; Martin Venker
2015-01-29T23:59:59.000Z
We study a class of interacting particle systems on $\\mathbb{R}$ which was recently investigated by F. G\\"otze and the second author ([GV14]). These ensembles generalize eigenvalue ensembles of Hermitian random matrices by allowing different interactions between particles. Although these ensembles are not known to be determinantal one can use the stochastic linearization method of [GV14] to represent them as averages of determinantal ones. We prove that the local correlations of the particles at the edge of the support of the limiting measure are universal and equal those for the eigenvalue ensembles. In particular, they are given in terms of the Airy kernel. Moreover, we prove that the largest particle converges, appropriately rescaled, to the Tracy-Widom distribution. In the regime of the Limit Law the averaging only shows through a weaker bound on the rate of convergence. We also obtain the leading order behavior of the upper tail of the distribution of the largest particle in a significant part of the regime of moderate deviations. For the averaging procedure we need detailed asymptotic information on the behavior of Christoffel-Darboux kernels, uniformly for a perturbative family of weights. Such results have been provided by K. Schubert, K. Sch\\"uler and the authors in [KSSV14].
Cutting-edge issues of core-collapse supernova theory
Kotake, Kei [Department of Applied Physics, Faculty of Science, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180 (Japan); Nakamura, Ko [Faculty of Science and Engineering, Waseda University, Ohkubo 3-4-1, Shinjuku, Tokyo, 169-8555 (Japan); Kuroda, Takami [Department Physik, Universität Basel, Klingelbergstrasse 82, 4056 Basel (Switzerland); Takiwaki, Tomoya [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo, 181-8588 (Japan)
2014-05-02T23:59:59.000Z
Based on multi-dimensional neutrino-radiation hydrodynamic simulations, we report several cutting-edge issues about the long-veiled explosion mechanism of core-collapse supernovae (CCSNe). In this contribution, we pay particular attention to whether three-dimensional (3D) hydrodynamics and/or general relativity (GR) would or would not help the onset of explosions. By performing 3D simulations with spectral neutrino transport, we show that it is more difficult to obtain an explosion in 3D than in 2D. In addition, our results from the first generation of full general relativistic 3D simulations including approximate neutrino transport indicate that GR can foster the onset of neutrino-driven explosions. Based on our recent parametric studies using a light-bulb scheme, we discuss impacts of nuclear energy deposition behind the supernova shock and stellar rotation on the neutrino-driven mechanism, both of which have yet to be included in the self-consistent 3D supernova models. Finally we give an outlook with a summary of the most urgent tasks to extract the information about the explosion mechanisms from multi-messenger CCSN observables.
Frozen light in photonic crystals with degenerate band edge
A. Figotin; I. Vitebskiy
2006-10-09T23:59:59.000Z
Consider a plane monochromatic wave incident on a semi-infinite periodic structure. What happens if the normal component of the transmitted wave group velocity vanishes? At first sight, zero normal component of the transmitted wave group velocity simply implies total reflection of the incident wave. But we demonstrate that total reflection is not the only possible outcome. Instead, the transmitted wave can appear in the form of a frozen mode with very large diverging amplitude and either zero, or purely tangential energy flux. The field amplitude in the transmitted wave can exceed that of the incident wave by several orders of magnitude. There are two qualitatively different kinds of frozen mode regime. The first one is associated with a stationary inflection point of electromagnetic dispersion relation. This phenomenon has been analyzed in our previous publications. Now, our focus is on the frozen mode regime related to a degenerate photonic band edge. An advantage of this new phenomenon is that it can occur in much simpler periodic structures. This spectacular effect is extremely sensitive to the frequency and direction of propagation of the incident plane wave. These features can be very attractive in a variety practical applications, such as higher harmonic generation and wave mixing, light amplification and lasing, highly efficient superprizms, etc.
Hirooka, Y. [Univ. of California, San Diego, La Jolla, CA (United States); Ashida, K. [Toyama Univ. (Japan); Kugel, H. [Princeton Univ., NJ (United States)] [and others
1998-05-01T23:59:59.000Z
Recent observations have indicated that lithium pellet injection wall conditioning plays an important role in achieving the enhanced supershot regime in TFTR. However, little is understood about the behavior of lithium-coated limiter walls, interacting with edge plasmas. In the final campaign of TFTR, a cylindrical carbon fiber composite probe was inserted into the boundary plasma region and exposed to ohmically-heated deuterium discharges with lithium pellet injection. The ion-drift side probe surface exhibits a sign of codeposition of lithium, carbon, oxygen, and deuterium, whereas the electron side essentially indicates high-temperature erosion. It is found that lithium is incorporated in these codeposits in the form of oxide at the concentration of a few percent. In the electron side, lithium has been found to penetrate deeply into the probe material, presumably via rapid diffusion through interplane spaces in the graphite crystalline. Though it is not conclusive, materials mixing in the carbon and lithium system appears to be a key process in successful lithium wall conditioning.
McDermott, Rachael Marie
2009-01-01T23:59:59.000Z
It is commonly accepted that ExB velocity shear is responsible for the suppression of edge turbulence, which reduces the losses of both energy and particles across magnetic field lines and results in the formation of edge ...
Numerical study of premixed twin edge flames in a counterflow field
Cho, Seong-Jin; Takita, Kenichi [Department of Aeronautics and Space Engineering, Tohoku University, Aramaki, Sendai 980-8579 (Japan)
2006-01-01T23:59:59.000Z
Characteristics of premixed edge flames established in a counterflow field with a stretch-rate gradient were numerically investigated by solving three-dimensional governing equations with detailed chemistry in the general curvilinear coordinates system. Local mole fractions of radicals, such as OH or CH, at the flame edge of a CH{sub 4}/air mixture were found to be larger than those in other parts of the flame. On the other hand, local mole fractions of radicals in the flame edge of a C{sub 3}H{sub 8}/air mixture were smaller than those in other parts. These numerical results agreed well with the experimental results of the present authors. Moreover, it was elucidated that two flame edges of twin counterflow flames did not merge at the edge even in the case of the CH{sub 4}/air mixture. The ratio of the local stretch rate at the flame edge to the extinction stretch rate for planar twin flames with the same equivalence ratio was 0.6 for the CH{sub 4}/air mixture and 0.7 for the C{sub 3}H{sub 8}/air mixture. These numerical results also agreed with results of the past experiments. Moreover, as for relatively low stretch-rate gradients, the stretch-rate gradient had no strong influence on the characteristics of the edge flames.
UHE Cosmic Rays and Neutrinos Showering on Planet Edges
D. Fargion; P. Oliva; O. Lanciano
2006-10-24T23:59:59.000Z
Ultra High Energy (UHE) Cosmic Rays, UHECR, may graze high altitude atmosphere leading to horizontal upward air-showers. Also PeVs electron antineutrino hitting electron in atmosphere may air-shower at W boson resonant mass. On the other side ultra high energy muon and electron neutrinos may also lead, by UHE neutrinos mass state mixing, to the rise of a corresponding UHE Tau neutrino flavor; the consequent UHE tau neutrinos, via charge current interactions in matter, may create UHE taus at horizons (Earth skimming neutrinos or Hor-taus) whose escape in atmosphere and whose consequent decay in flight, may be later amplified by upward showering on terrestrial, planetary atmospheres. Indeed because of the finite terrestrial radius, its thin atmosphere size its dense crust, the UHE tau cannot extend much more than 360 kilometers in air, corresponding to an energy of about 7.2 EeV, near but below GZK cut-off ones; on the contrary Jupiter (or even Saturn) may offer a wider, less dense and thicker gaseous layer at the horizons where Tau may loose little energy, travel longer before decay and rise and shower at 4-6 10^{19} eV or ZeV extreme energy. Titan atmosphere may open a rare window of opportunity for Up-ward Taus at PeVs. Also solar atmosphere may play a role, but unfortunately tau-showers secondaries maybe are too noisy to be disentangled, while Jupiter atmosphere, or better, Saturn one, may offer a clearer imprint for GZK (and higher Z-Burst) Tau showering, well below the horizons edges.
The Influence of Isotopic Mass, Edge Magnetic Shear and Input Power on High Density ELMy H-modes in JET
FIRST MEASUREMENT OF PRESSURE GRADIENT-DRIVEN CURRENTS IN TOKAMAK EDGE PLASMAS
THOMAS DM; LEONARD AW; LAO LL; OSBORNE TH; MUELLER HW; FINKENTHAL DK
2003-11-01T23:59:59.000Z
Localized currents driven by pressure gradients play a pivotal role in the magnetohydrodynamic stability of toroidal plasma confinement devices. We have measured the currents generated in the edge of L- (low) and H- (high confinement) mode discharges on the DIII-D tokamak, utilizing the Zeeman effect in an injected lithium beam to obtain high resolution profiles of the poloidal magnetic field. We find current densities in excess of 1 MA/m{sup 2} in a 1 to 2 cm region near the peak of the edge pressure gradient. These values are sufficient to challenge edge stability theories based on specific current formation models.
Bohm, P., E-mail: bohm@ipp.cas.cz; Bilkova, P.; Melich, R.; Sestak, D.; Weinzettl, V.; Stockel, J.; Hron, M.; Panek, R. [Institute of Plasma Physics ASCR, Za Slovankou 1782/3, 18200 Prague (Czech Republic); Aftanas, M.; Stefanikova, E.; Janky, F.; Havlicek, J. [Institute of Plasma Physics ASCR, Za Slovankou 1782/3, 18200 Prague (Czech Republic); Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16 Prague (Czech Republic); Mikulin, O. [Institute of Plasma Physics ASCR, Za Slovankou 1782/3, 18200 Prague (Czech Republic); Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University, Brehova 7, 11519 Prague (Czech Republic); Scannell, R.; Naylor, G. [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Frassinetti, L. [School of Electrical Engineering, Division of Fusion Plasma Physics, KTH Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Fassina, A. [Consorzio RFX, Corso Stati Uniti, 4-35127 Padua (Italy); Walsh, M. J. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul lez Durance (France)
2014-11-15T23:59:59.000Z
The core Thomson scattering diagnostic (TS) on the COMPASS tokamak was put in operation and reported earlier. Implementation of edge TS, with spatial resolution along the laser beam up to ?1/100 of the tokamak minor radius, is presented now. The procedure for spatial calibration and alignment of both core and edge systems is described. Several further upgrades of the TS system, like a triggering unit and piezo motor driven vacuum window shutter, are introduced as well. The edge TS system, together with the core TS, is now in routine operation and provides electron temperature and density profiles.
Hansen, Andrew J.
Hansen et al. Edge effects across ecosystem types 1 Ecosystem Biomass as a Framework for Predicting Habitat Fragmentation Effects Running Head: Edge effects across ecosystem types Key Words: biomass 59717-3460. hansen@montana.edu 25 February 2008 #12;Hansen et al. Edge effects across ecosystem types 2
B. M. Santos; M. Dutra; O. Lourenço; A. Delfino
2014-09-17T23:59:59.000Z
By using point-coupling versions of finite range nuclear relativistic mean field models containing cubic and quartic self interactions in the scalar field $\\sigma$, a nonrelativistic limit is achieved. This approach allows an analytical expression for the symmetry energy ($J$) as a function of its slope ($L$) in a unified form, namely, $\\,L\\,=\\,3J\\,+f(m^{*},\\rho_{o},B_{o},K_{o})$, where the quantities $m^{*}$, $\\rho_{o}$, $B_{o}$ and $K_{o}$ are bulk parameters at the nuclear matter saturation density $\\rho_{o}$. This result establishes a linear correlation between $L$ and $J$ which is reinforced by exact relativistic calculations. An analogous analytical correlation is also found for $J$, $L$ and the symmetry energy curvature ($K_{sym}$). Based on these results, we propose graphic constraints in $L\\times J$ and $K_{sym}\\times L$ planes which finite range models must satisfy.
ELM Suppression in Low Edge Collisionality H-Mode Discharges Using n=3 Magnetic Perturbations
Burrell, K H; Evans, T E; Doyle, E J; Fenstermacher, M E; Groebner, R J; Leonard, A W; Moyer, R A; Osborne, T H; Schaffer, M J; Snyder, P B; Thomas, P R; West, W P; Boedo, J A; Garofalo, A M; Gohil, P; Jackson, G L; La Haye, R J; Lasnier, C J; Reimerdes, H; Rhodes, T L; Scoville, J T; Solomon, W M; Thomas, D M; Wang, G; Watkins, J G; Zeng, L
2005-07-11T23:59:59.000Z
Using resonant magnetic perturbations with toroidal mode number n = 3, we have produced H-mode discharges without edge localized modes (ELMs) which run with constant density and radiated power for periods up to about 2550 ms (17 energy confinement times). These ELM suppression results are achieved at pedestal collisionalities close to those desired for next step burning plasma experiments such as ITER and provide a means of eliminating the rapid erosion of divertor components in such machines which could be caused by giant ELMs. The ELM suppression is due to an enhancement in the edge particle transport which reduces the edge pressure gradient and pedestal current density below the threshold for peeling-ballooning modes. These n = 3 magnetic perturbations provide a means of active control of edge plasma transport.
Evans, T E; Moyer, R A; Burrell, K H; Fenstermacher, M E; Joseph, I; Leonard, A W; Osborne, T H; Porter, G D; Schaffer, M J; Snyder, P B; Thomas, P R; Watkins, J G; West, W P
2006-06-13T23:59:59.000Z
A critical issue for fusion plasma research is the erosion of the first wall of the experimental device due to impulsive heating from repetitive edge magneto-hydrodynamic (MHD) instabilities known as 'edge-localized modes' (ELMs). Here, we show that the addition of small resonant magnetic field perturbations completely eliminates ELMs while maintaining a steady-state high-confinement (H-mode) plasma. These perturbations induce a chaotic behavior in the magnetic field lines, which reduces the edge pressure gradient below the ELM instability threshold. The pressure gradient reduction results from a reduction in particle content of the plasma, rather than an increase in the electron thermal transport. This is inconsistent with the predictions of stochastic electron heat transport theory. These results provide a first experimental test of stochastic transport theory in a highly rotating, hot, collisionless plasma and demonstrate a promising solution to the critical issue of controlling edge instabilities in fusion plasma devices.
Edge transport barrier studies on the Alcator C-Mod tokamak
Hughes, Jerry W. (Jerry Wayne), 1975-
2005-01-01T23:59:59.000Z
Edge transport barriers (ETBs) in tokamak plasmas accompany transitions from low confinement (L-mode) to high confinement (H-mode) and exhibit large density and temperature gradients in a narrow pedestal region near the ...
Observation of Edge Instability Limiting the Pedestal Growth in Tokamak Plasmas
Diallo, A.
With fusion device performance hinging on the edge pedestal pressure, it is imperative to experimentally understand the physical mechanism dictating the pedestal characteristics and to validate and improve pedestal predictive ...
Quality Evaluation of Motion-Compensated Edge Artifacts in Compressed Video
Leontaris, Athanasios; Cosman, Pamela C; Reibman, Amy R
2007-01-01T23:59:59.000Z
at block boundaries (off grid). Fractional-pixel MC andand “noisier” refers to off-grid edge artifacts (MCEA).DC values. Since MC causes off-grid blocking artifacts, most
Suppressing traffic-driven epidemic spreading by edge-removal strategies
Yang, Han-Xin; Wang, Bing-Hong
2015-01-01T23:59:59.000Z
The interplay between traffic dynamics and epidemic spreading on complex networks has received increasing attention in recent years. However, the control of traffic-driven epidemic spreading remains to be a challenging problem. In this Brief Report, we propose a method to suppress traffic-driven epidemic outbreak by properly removing some edges in a network. We find that the epidemic threshold can be enhanced by the targeted cutting of links among large-degree nodes or edges with the largest algorithmic betweeness. In contrast, the epidemic threshold will be reduced by the random edge removal. These findings are robust with respect to traffic-flow conditions, network structures and routing strategies. Moreover, we find that the shutdown of targeted edges can effectively release traffic load passing through large-degree nodes, rendering a relatively low probability of infection to these nodes.
antenna-coupled transition edge: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Ming Ko; Lie-Wen Chen; Bao-an Li; Hong-Ru Ma 2009-11-05 30 Development of a gamma-ray detector with iridium transition edge sensor coupled to a Pb absorber MIT - DSpace Summary: We...
The displacement field characterization of two interacting parallel edge cracks in a finite body
Keener, Todd Whitney
1996-01-01T23:59:59.000Z
The goals of this research were to: (1) develop a model to represent the displacement field surrounding two interacting, parallel edge cracks; and (2) use this model to investigate the influence of crack separation and relative crack length...
Long-Wavelength Local Density of States Oscillations Near Graphene Step Edges
Xue, Jiamin
Using scanning tunneling microscopy and spectroscopy, we have studied the local density of states (LDOS) of graphene over step edges in boron nitride. Long-wavelength oscillations in the LDOS are observed with maxima ...
Accreted oceanic terranes in Ecuador : Southern edge of the Caribbean plate ?
Paris-Sud XI, UniversitĂ© de
Accreted oceanic terranes in Ecuador : Southern edge of the Caribbean plate ? Etienne Jaillard (1 plateau of Ecuador is interpreted as part of the Caribbean ocean- ic plateau (COP), because
RESEARCH ARTICLE On the stabilization of leading-edge vortices with spanwise flow
Croskey (1982). During such an event, the boundary- layer separation moves rapidly forward to the leading edge prevalent shape. However, the specific fluid-dynamic role of this planform during oscillatory motions has
The stress field around two parallel edge cracks in a finite body
Hardin, Patrick Wayne
1993-01-01T23:59:59.000Z
The goal of this research was to develop a method to represent and analyze the stress field surrounding two edge cracks located in a finite body. The generalized Westergaard equations were utilized to represent the independent stress fields created...
Analysis of Edge Schema Contained in jdbc:microsoft:sqlserver://db-
McBrien, Peter
.doc.ic.ac.uk;databaseName=dblp XMLtoEdgeSchema program, Peter Mc.Brien pjm@doc.ic.ac.uk http://www.doc.ic.ac.uk/ pjm May 16, 2003 1 #12
Space-Time Coding for the EDGE Mobile Radio System Marceau Coupechoux
Coupechoux, Marceau
28 Space-Time Coding for the EDGE Mobile Radio System Marceau Coupechoux Alcatel CorporateResearchCenter Route de Nozay, 91460 Marcoussis. France Phone: +33- 169-63-4359, e-mail: marceau
Electric field control of spin-resolved edge states in graphene quantum nanorings
Farghadan, R., E-mail: rfarghadan@kashanu.ac.ir [Department of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Saffarzadeh, A. [Department of Physics, Payame Noor University, P.O. Box 19395-3697, Tehran (Iran, Islamic Republic of); Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6 (Canada)
2014-05-07T23:59:59.000Z
The electric-field effect on the electronic and magnetic properties of triangular and hexagonal graphene quantum rings with zigzag edge termination is investigated by means of the single-band tight-binding Hamiltonian and the mean-field Hubbard model. It is shown how the electron and spin states in the nanoring structures can be manipulated by applying an electric field. We find different spin-depolarization behaviors with variation of electric field strength due to the dependence of spin densities on the shapes and edges of this kind of nanorings. In the case of triangular quantum rings, the magnetization on the inner and outer edges can be selectively tuned and the spin states depolarize gradually as the field strength is increased, while in the case of hexagonal nanorings, the transverse electric field reduces the magnetic moments on both inner and outer edges symmetrically and rapidly.
NUMBER CRUNCHING ISSUE SUMMER BRINGING CUTTING EDGE SCIENCE INTO THE CLASSROOM
Rambaut, Andrew
NUMBER CRUNCHING ISSUE SUMMER BRINGING CUTTING EDGE SCIENCE INTO THE CLASSROOM MAKING SENSE the same result because of chance or other unknown factors. In science, a hypothesis is the explanation you
Cutting Edge: In the Absence of TGF-b Signaling in T Cells, Fewer CD103+
Maizels, Rick
Cutting Edge: In the Absence of TGF-b Signaling in T Cells, Fewer CD103+ Regulatory T Cells Develop. Maizels Multiple factors control susceptibility of C57BL/6 mice to infection with the helminth
Evaluation and Modeling of Edge-Seal Materials for Photovoltaic Applications
Kempe, M. D.; Dameron, A. A.; Moricone, T. J.; Reese, M. O.
2011-02-01T23:59:59.000Z
Because of the sensitivity of some photovoltaic devices to moisture-induced corrosion, they are packaged using impermeable front- and back-sheets along with an edge seal to prevent moisture ingress. Evaluation of edge seal materials can be difficult because of the low permeation rates involved and/or non-Fickian behavior. Here, using a Ca film deposited on a glass substrate, we demonstrate the evaluation of edge seal materials in a manner that effectively duplicates their use in a photovoltaic application and compare the results with standard methods for measuring water vapor transport. We demonstrate how moisture permeation data from polymer films can be used to estimate moisture ingress rates and compare the results of these two methods. Encapsulant materials were also evaluated for comparison and to highlight the need for edge seals. Of the materials studied, desiccant filled polyisobutylene materials demonstrate by far the best potential to keep moisture out for a 20 to 30 year lifetime.
Calcium Film Based Testing of Edge-Seal Materials for Photovoltaic Applications (Presentation)
Kempe, M.; Dameron, A.; Reese, M.
2011-04-01T23:59:59.000Z
Because of the sensitivity of some photovoltaic devices to moisture-induced corrosion, they are packaged using impermeable front- and back-sheets with an edge seal to prevent moisture ingress. Evaluation of edge seal materials can be difficult because of the low permeation rates involved and/or non-Fickian behavior. Here, using a Ca film deposited on a glass substrate, we demonstrate the evaluation of edge seal materials in a manner that effectively duplicates their use in a photovoltaic application and compare the results with standard methods for measuring water vapor transport. We demonstrate how moisture permeation data from polymer films can be used to estimate moisture ingress rates and compare the results of these two methods. Encapsulant materials were also evaluated for comparison and to highlight the need for edge seals. Of the materials studied, dessicant-filled polyisobutene materials demonstrate by far the best potential to keep moisture out for a 20 to 30 year lifetime.
Calcium Based Test Method for Evaluation of Photovoltaic Edge-Seal Materials (Presentation)
Kempe, M.; Dameron, A.; Reese, M.
2011-02-01T23:59:59.000Z
Because of the sensitivity of some photovoltaic devices to moisture-induced corrosion, they are packaged using impermeable front- and back-sheets with an edge seal to prevent moisture ingress. Evaluation of edge seal materials can be difficult because of the low permeation rates involved and/or non-Fickian behavior. Here, using a Ca film deposited on a glass substrate, we demonstrate the evaluation of edge seal materials in a manner that effectively duplicates their use in a photovoltaic application and compare the results with standard methods for measuring water vapor transport. We demonstrate how moisture permeation data from polymer films can be used to estimate moisture ingress rates and compare the results of these two methods. Encapsulant materials were also evaluated for comparison and to highlight the need for edge seals. Of the materials studied, dessicant-filled polyisobutene materials demonstrate by far the best potential to keep moisture out for a 20 to 30 year lifetime.
Gas turbine bucket wall thickness control
Stathopoulos, Dimitrios (Glenmont, NY); Xu, Liming (Greenville, SC); Lewis, Doyle C. (Greer, SC)
2002-01-01T23:59:59.000Z
A core for use in casting a turbine bucket including serpentine cooling passages is divided into two pieces including a leading edge core section and a trailing edge core section. Wall thicknesses at the leading edge and the trailing edge of the turbine bucket can be controlled independent of each other by separately positioning the leading edge core section and the trailing edge core section in the casting die. The controlled leading and trailing edge thicknesses can thus be optimized for efficient cooling, resulting in more efficient turbine operation.
Cummings, Julian C. [California Institute of Technology
2013-05-15T23:59:59.000Z
This project was a collaboration between researchers at the California Institute of Technology and the University of California, Irvine to investigate the utility of a global field-aligned mesh and gyrokinetic field solver for simulations of the tokamak plasma edge region. Mesh generation software from UC Irvine was tested with specific tokamak edge magnetic geometry scenarios and the quality of the meshes and the solutions to the gyrokinetic Poisson equation were evaluated.
A modified greedy channel router with net assignment at the left edge
Oh, Chuldong
1987-01-01T23:59:59.000Z
A MODIFIED GREEDY CHANNEL ROUTER WITH NET ASSIGNMENT AT THE LEFT EDGE A Thesis by CHULDONG OH Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August... 1987 Major Subject: Electrical Engineering A MODIFIED GREEDY CHANNEL ROUTER WITH NET ASSIGNMENT AT THE LEFT EDGE A Thesis by CHULDONG OH Approved as to style and content by: Karan L. Watson (Chairman of Committee) hilip S. Noe (Member...
Acquisition and reconstruction of brain tissue using knife-edge scanning microscopy
Mayerich, David Matthew
2004-09-30T23:59:59.000Z
ACQUISITION AND RECONSTRUCTION OF BRAIN TISSUE USING KNIFE- EDGE SCANNING MICROSCOPY A Thesis by DAVID MATTHEW MAYERICH Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE December 2003 Major Subject: Computer Science ACQUISITION AND RECONSTRUCTION OF BRAIN TISSUE USING KNIFE- EDGE SCANNING MICROSCOPY A Thesis by DAVID MATTHEW MAYERICH Submitted to Texas...
Dynamics and generation mechanisms of mesoscale structures in tokamak edge plasmas
Krasheninnikov, S. I. [University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093 (United States); Smolyakov, A. I. [University of Saskatchewan, 116 Science Place, Saskatoon, Saskatchewan S7N 5E2 (Canada)
2008-05-15T23:59:59.000Z
Intermittent convective-like plasma transport associated with mesoscale coherent structures extended along the magnetic field lines (''blobs'') is often dominant at the edge of tokamaks, stellarators, and linear devices. Blobs can travel a large distance toward the wall ({approx}10 cm and larger) and strongly enhance both edge plasma energy and particle transport and plasma-wall interactions. The dynamics of blobs and blob generation mechanisms are discussed in this paper.
SINTEF Building and Infrastructure; Norwegian University of Science and Technology (NTNU); Bergh, Sofie Van Den; Hart, Robert; Jelle, Bjrn Petter; Gustavsen, Arild
2013-01-31T23:59:59.000Z
Insulating glass (IG) units typically consist of multiple glass panes that are sealed and held together structurally along their perimeters. This report describes a study of edge seals in IG units. First, we summarize the components, requirements, and desired properties of edge construction in IG units, based on a survey of the available literature. Second, we review commercially available window edge seals and describe their properties, to provide an easily accessible reference for research and commercial purposes. Finally, based on the literature survey and review of current commercial edge seal systems, we identify research opportunities for future edge seal improvements and solutions.
Bochev, Pavel Blagoveston
2011-06-01T23:59:59.000Z
We develop a new formulation of the Control Volume Finite Element Method (CVFEM) with a multidimensional Scharfetter-Gummel (SG) upwinding for the drift-diffusion equations. The formulation uses standard nodal elements for the concentrations and expands the flux in terms of the lowest-order Nedelec H(curl; {Omega})-compatible finite element basis. The SG formula is applied to the edges of the elements to express the Nedelec element degree of freedom on this edge in terms of the nodal degrees of freedom associated with the endpoints of the edge. The resulting upwind flux incorporates the upwind effects from all edges and is defined at the interior of the element. This allows for accurate evaluation of integrals on the boundaries of the control volumes for arbitrary quadrilateral elements. The new formulation admits efficient implementation through a standard loop over the elements in the mesh followed by loops over the element nodes (associated with control volume fractions in the element) and element edges (associated with flux degrees of freedom). The quantities required for the SG formula can be precomputed and stored for each edge in the mesh for additional efficiency gains. For clarity the details are presented for two-dimensional quadrilateral grids. Extension to other element shapes and three dimensions is straightforward.
Edge effects in graphene nanostructures: I. From multiple reflection expansion to density of states
J. Wurm; K. Richter; I. Adagideli
2011-08-06T23:59:59.000Z
We study the influence of different edge types on the electronic density of states of graphene nanostructures. To this end we develop an exact expansion for the single particle Green's function of ballistic graphene structures in terms of multiple reflections from the system boundary, that allows for a natural treatment of edge effects. We first apply this formalism to calculate the average density of states of graphene billiards. While the leading term in the corresponding Weyl expansion is proportional to the billiard area, we find that the contribution that usually scales with the total length of the system boundary differs significantly from what one finds in semiconductor-based, Schr\\"odinger type billiards: The latter term vanishes for armchair and infinite mass edges and is proportional to the zigzag edge length, highlighting the prominent role of zigzag edges in graphene. We then compute analytical expressions for the density of states oscillations and energy levels within a trajectory based semiclassical approach. We derive a Dirac version of Gutzwiller's trace formula for classically chaotic graphene billiards and further obtain semiclassical trace formulae for the density of states oscillations in regular graphene cavities. We find that edge dependent interference of pseudospins in graphene crucially affects the quantum spectrum.
MyRED Registration Audit Trail Registration Audit Trail
Farritor, Shane
ID and indicate the term you wish to view. Click Search. If you don't indicate the term before you click Search, a list of applicable terms to select from will appear below. September 15, 2011 a particular course, enter the Subject Area and/or Catalog Nbr into the Filter and click Search. 1 #12;My
Bootstrap Current for the Edge Pedestal Plasma in a Diverted Tokamak Geometry
Koh, S.; Chang, C. S.; Ku, S.; Menard, J. E.; Weitzner, H.; Choe, W.
2012-08-10T23:59:59.000Z
The edge bootstrap current plays a critical role in the equilibrium and stability of the steep edge pedestal plasma. The pedestal plasma has an unconventional and difficult neoclassical property, as compared with the core plasma. It has a narrow passing particle region in velocity space that can be easily modified or destroyed by Coulomb collisions. At the same time, the edge pedestal plasma has steep pressure and electrostatic potential gradients whose scale-lengths are comparable with the ion banana width, and includes a magnetic separatrix surface, across which the topological properties of the magnetic field and particle orbits change abruptly. A driftkinetic particle code XGC0, equipped with a mass-momentum-energy conserving collision operator, is used to study the edge bootstrap current in a realistic diverted magnetic field geometry with a self-consistent radial electric field. When the edge electrons are in the weakly collisional banana regime, surprisingly, the present kinetic simulation confirms that the existing analytic expressions [represented by O. Sauter et al. , Phys. Plasmas 6 , 2834 (1999)] are still valid in this unconventional region, except in a thin radial layer in contact with the magnetic separatrix. The agreement arises from the dominance of the electron contribution to the bootstrap current compared with ion contribution and from a reasonable separation of the trapped-passing dynamics without a strong collisional mixing. However, when the pedestal electrons are in plateau-collisional regime, there is significant deviation of numerical results from the existing analytic formulas, mainly due to large effective collisionality of the passing and the boundary layer trapped particles in edge region. In a conventional aspect ratio tokamak, the edge bootstrap current from kinetic simulation can be significantly less than that from the Sauter formula if the electron collisionality is high. On the other hand, when the aspect ratio is close to unity, the collisional edge bootstrap current can be significantly greater than that from the Sauter formula. Rapid toroidal rotation of the magnetic field lines at the high field side of a tight aspect-ratio tokamak is believed to be the cause of the different behavior. A new analytic fitting formula, as a simple modification to the Sauter formula, is obtained to bring the analytic expression to a better agreement with the edge kinetic simulation results
J. Wurm; K. Richter; I. Adagideli
2011-11-14T23:59:59.000Z
We investigate the effect of different edge types on the statistical properties of both the energy spectrum of closed graphene billiards and the conductance of open graphene cavities in the semiclassical limit. To this end, we use the semiclassical Green's function for ballistic graphene flakes that we have derived in Reference 1. First we study the spectral two point correlation function, or more precisely its Fourier transform the spectral form factor, starting from the graphene version of Gutzwiller's trace formula for the oscillating part of the density of states. We calculate the two leading order contributions to the spectral form factor, paying particular attention to the influence of the edge characteristics of the system. Then we consider transport properties of open graphene cavities. We derive generic analytical expressions for the classical conductance, the weak localization correction, the size of the universal conductance fluctuations and the shot noise power of a ballistic graphene cavity. Again we focus on the effects of the edge structure. For both, the conductance and the spectral form factor, we find that edge induced pseudospin interference affects the results significantly. In particular intervalley coupling mediated through scattering from armchair edges is the key mechanism that governs the coherent quantum interference effects in ballistic graphene cavities.
A General Theorem Relating the Bulk Topological Number to Edge States in Two-dimensional Insulators
Qi, Xiao-Liang; /Tsinghua U., Beijing /Stanford U., Phys. Dept.; Wu, Yong-Shi; /Utah U.; Zhang, Shou-Cheng; /Stanford U., Phys. Dept. /Tsinghua U., Beijing
2010-01-15T23:59:59.000Z
We prove a general theorem on the relation between the bulk topological quantum number and the edge states in two dimensional insulators. It is shown that whenever there is a topological order in bulk, characterized by a non-vanishing Chern number, even if it is defined for a non-conserved quantity such as spin in the case of the spin Hall effect, one can always infer the existence of gapless edge states under certain twisted boundary conditions that allow tunneling between edges. This relation is robust against disorder and interactions, and it provides a unified topological classification of both the quantum (charge) Hall effect and the quantum spin Hall effect. In addition, it reconciles the apparent conflict between the stability of bulk topological order and the instability of gapless edge states in systems with open boundaries (as known happening in the spin Hall case). The consequences of time reversal invariance for bulk topological order and edge state dynamics are further studied in the present framework.
Viganň, Daniele
2015-01-01T23:59:59.000Z
$\\gamma$-ray spectra of pulsars have been mostly studied in a phenomenological way, by fitting them to a cut-off power-law function. Here, we analyze a model where pulsed emission comes from synchro-curvature processes in a gap. We calculate the variation of kinetic energy of magnetospheric particles along the gap and the associated radiated spectra, considering an effective particle distribution. We fit the phase-averaged and phase-resolved {\\em Fermi}-LAT spectra of the three brightest $\\gamma$-ray pulsars: Geminga, Crab, and Vela, and constrain the three free parameters we leave free in the model. Our best-fit models well reproduce the observed data, apart from residuals above a few GeV in some cases, range for which the inverse Compton scattering likely becomes the dominant mechanism. In any case, the flat slope at low-energy ($\\lesssim$ GeV) seen by {\\it Fermi}-LAT both in the phase-averaged and phase-resolved spectra of most pulsars, including the ones we studied, requires that most of the detected radi...
Congedo, Giuseppe
2015-01-01T23:59:59.000Z
The measurement of frequency shifts for light beams exchanged between two test masses nearly in free fall is at the heart of gravitational wave detection. It is envisaged that the derivative of the frequency shift is in fact limited by differential forces acting on those test masses. We calculate the derivative of the frequency shift with a fully covariant, gauge-independent and coordinate-free method. This method is general and does not require a congruence of nearby beams' null geodesics as done in previous work. We show that the derivative of the parallel transport is the only means by which gravitational effects shows up in the frequency shift. This contribution is given as an integral of the Riemann tensor --the only physical observable of curvature-- along the beam's geodesic. The remaining contributions are: the difference of velocities, the difference of non-gravitational forces, and finally fictitious forces, either locally at the test masses or non-locally integrated along the beam's geodesic. As an...
Cooking with Trail Mix (Spanish)
Anding, Jenna
2008-12-09T23:59:59.000Z
Life Communications, El Sistema Texas A&M Las publicaciones de Texas AgriLife Extension se pueden encontrar en Internet en: http://AgriLifebookstore.org Los programas educativos de Texas AgriLife Extension Service est?n disponibles para todas las personas, sin...
Cooking with Trail Mix (Spanish)
Anding, Jenna
2008-12-09T23:59:59.000Z
Nutrici?n, El Sistema Texas A&M. Usos La mezcla de frutos secos es un bocadillo r?pido y f?cil. S?rvalo directamente del paquete. Tambi?n puede a?adir los frutos secos a su cereal matutino favorito o a una receta de panquecitos. Almacenamiento Para... asegurar la mejor calidad conserve los paquetes sin abrir de mezcla de frutos en un sitio fresco y seco. Una vez abierto el paquete, guarde la mezcla en un envase herm?tico. Util?cela antes de que transcurran 6 meses. Producido por Agri...
Pioneer Trail | 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 onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation,Pillar Group BV Jump to: navigation, search Name: PillarPinnaclePioneer Prairie
TWP Island Cloud Trail Studies
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructureProposedPAGE Creating a Geologic5/15/2013May 7, 2014Pacific
Visualizing edge states with an atomic Bose gas in the quantum Hall regime
Stuhl, B K; Aycock, L M; Genkina, D; Spielman, I B
2015-01-01T23:59:59.000Z
We engineered a two-dimensional magnetic lattice in an elongated strip geometry, with effective per-plaquette flux ~4/3 times the flux quanta. We imaged the localized edge and bulk states of atomic Bose-Einstein condensates in this strip, with single lattice-site resolution along the narrow direction. Further, we observed both the skipping orbits of excited atoms traveling down our system's edges, analogues to edge magnetoplasmons in 2-D electron systems, and a dynamical Hall effect for bulk excitations. Our lattice's long direction consisted of the sites of an optical lattice and its narrow direction consisted of the internal atomic spin states. Our technique has minimal heating, a feature that will be important for spectroscopic measurements of the Hofstadter butterfly and realizations of Laughlin's charge pump.
High-Q band edge mode of plasmonic crystals studied by cathodoluminescence
Honda, Masahiro; Yamamoto, Naoki, E-mail: nyamamot@phys.titech.ac.jp [Department of Physics, Tokyo Institute of Technology, Tokyo 152-8551 (Japan)
2014-02-24T23:59:59.000Z
We have investigated the quality factor (Q-factor) of the band edge modes in the plasmonic crystal by a cathodoluminescence technique. We have found that the Q-factor at the ? point depends on the terrace width (D)/period (P) ratio of the plasmonic crystal. The finite-difference time-domain methods predict that the band edge mode at D/P?=?3/4 has a high-Q-factor (Q???250 by Palik's permittivity data and Q???530 by Johnson and Christy's data). The beam-scan spectral images allowed us to visualize the standing surface plasmon polariton waves at the band edge energies, and a high-Q-factor of ?200 was observed at D/P???3/4.
Visualizing edge states with an atomic Bose gas in the quantum Hall regime
B. K. Stuhl; H. -I Lu; L. M. Aycock; D. Genkina; I. B. Spielman
2015-02-09T23:59:59.000Z
We engineered a two-dimensional magnetic lattice in an elongated strip geometry, with effective per-plaquette flux ~4/3 times the flux quanta. We imaged the localized edge and bulk states of atomic Bose-Einstein condensates in this strip, with single lattice-site resolution along the narrow direction. Further, we observed both the skipping orbits of excited atoms traveling down our system's edges, analogues to edge magnetoplasmons in 2-D electron systems, and a dynamical Hall effect for bulk excitations. Our lattice's long direction consisted of the sites of an optical lattice and its narrow direction consisted of the internal atomic spin states. Our technique has minimal heating, a feature that will be important for spectroscopic measurements of the Hofstadter butterfly and realizations of Laughlin's charge pump.
Observation of phononic helical edge states in a mechanical 'topological insulator'
Süsstrunk, Roman
2015-01-01T23:59:59.000Z
A topological insulator is characterized by a dichotomy between the interior and the edge of a finite system: While the bulk has a non-zero energy gap, the edges are forced to sustain excitations traversing these gaps. Originally proposed for electrons governed by quantum mechanics, it has remained an important open question if the same physics can be observed for systems obeying Newton's equations of motion. Here, we report on measurements that characterize the collective behavior of mechanical oscillators exhibiting the phenomenology of the quantum spin hall effect. The phononic edge modes are shown to be helical and we demonstrate their topological protection via the stability against imperfections. Our results open the door to the design of topological acoustic meta-materials that can capitalize on the stability of the surfaces phonons as reliable wave guides.
Operator-Schmidt decomposition and the geometrical edges of two-qubit gates
S. Balakrishnan; R. Sankaranarayanan
2011-06-30T23:59:59.000Z
Nonlocal two-qubit quantum gates are represented by canonical decomposition or equivalently by operator-Schmidt decomposition. The former decomposition results in geometrical representation such that all the two-qubit gates form tetrahedron within which perfect entanglers form a polyhedron. On the other hand, it is known from the later decomposition that Schmidt number of nonlocal gates can be either 2 or 4. In this work, some aspects of later decomposition are investigated. It is shown that two gates differing by local operations possess same set of Schmidt coefficients. Employing geometrical method, it is established that Schmidt number 2 corresponds to controlled unitary gates. Further, all the edges of tetrahedron and polyhedron are characterized using Schmidt strength, a measure of operator entanglement. It is found that one edge of the tetrahedron possesses the maximum Schmidt strength, implying that all the gates in the edge are maximally entangled.
Operator-Schmidt decomposition and the geometrical edges of two-qubit gates
Balakrishnan, S
2010-01-01T23:59:59.000Z
Nonlocal two-qubit quantum gates are represented by canonical decomposition or equivalently by operator-Schmidt decomposition. The former decomposition results in geometrical representation such that all the two-qubit gates form tetrahedron within which perfect entanglers form a polyhedron. On the other hand, it is known from the later decomposition that Schmidt number of nonlocal gates can be either 2 or 4. In this work, some aspects of later decomposition are investigated. It is shown that two gates differing by local operations possess same set of Schmidt coefficients. Employing geometrical method, it is established that Schmidt number 2 corresponds to controlled unitary gates. Further, all the edges of tetrahedron and polyhedron are characterized using Schmidt strength, a measure of operator entanglement. It is found that one edge of the tetrahedron possesses the maximum Schmidt strength, implying that all the gates in the edge are maximally entangled.
Helayeel-Neto, J. A.; Hernaski, C. A.; Pereira-Dias, B.; Vargas-Paredes, A. A.; Vasquez-Otoya, V. J. [Centro Brasileiro de Pesquisas Fisicas, Rua Dr. Xavier Sigaud 150, Urca, Rio de Janeiro, Brazil, CEP 22290-180 (Brazil)
2010-09-15T23:59:59.000Z
The effects of (curvature){sup 2}- and (torsion){sup 2}-terms in the Einstein-Hilbert-Chern-Simons Lagrangian are investigated. The purposes are two-fold: (i) to show the efficacy of an orthogonal basis of degree-of-freedom projection operators recently proposed and to ascertain its adequacy for obtaining propagators of general parity-breaking gravity models in three dimensions; (ii) to analyze the role of the topological Chern-Simons term for the unitarity and the particle spectrum of the model squared-curvature terms in connection with dynamical torsion. Our conclusion is that the Chern-Simons term does not influence the unitarity conditions imposed on the parameters of the Lagrangian but significantly modifies the particle spectrum.
Igor Romanovsky; Constantine Yannouleas; Uzi Landman
2012-10-17T23:59:59.000Z
Systematic tight-binding investigations of the electronic spectra (as a function of the magnetic field) are presented for trigonal graphene nanoflakes with reconstructed zigzag edges, where a succession of pentagons and heptagons, that is 5-7 defects, replaces the hexagons at the zigzag edge. For nanoflakes with such reczag defective edges, emphasis is placed on topological aspects and connections underlying the patterns dominating these spectra. The electronic spectra of trigonal graphene nanoflakes with reczag edge terminations exhibit certain unique features, in addition to those that are well known to appear for graphene dots with zigzag edge termination. These unique features include breaking of the particle-hole symmetry, and they are associated with nonlinear dispersion of the energy as a function of momentum, which may be interpreted as nonrelativistic behavior. The general topological features shared with the zigzag flakes include the appearance of energy gaps at zero and low magnetic fields due to finite size, the formation of relativistic Landau levels at high magnetic fields, and the presence between the Landau levels of edge states (the socalled Halperin states) associated with the integer quantum Hall effect. Topological regimes, unique to the reczag nanoflakes, appear within a stripe of negative energies E_b < E < 0, and along a separate feature forming a constant-energy line outside this stripe. The lower bound (E_b) specifying the energy stripe is independent of size. A main finding concerns the limited applicability of the continuous Dirac-Weyl equation, since the latter does not reproduce the special reczag features. (See also the extended abstract in the paper.)
Roman G. Smirnov; Jin Yue
2004-08-03T23:59:59.000Z
The invariant theory of Killing tensors (ITKT) is extended by introducing the new concepts of covariants and joint invariants of (product) vector spaces of Killing tensors defined in pseudo-Riemannian spaces of constant curvature. The covariants are employed to solve the problem of classification of the orthogonal coordinate webs generated by non-trivial Killing tensors of valence two defined in the Euclidean and Minkowski planes. Illustrative examples are provided.
The effects of a jet on vortex breakdown over a sharp leading-edge delta wing
Maynard, Ian Kenneth
1985-01-01T23:59:59.000Z
THE EFFECTS OF A JET ON VORTEX BREAKDOWN OVER A SHARP LEADING-EDGE DELTA WING A Thesis 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: Aerospace Engineering THE EFFECTS OF A JET ON VORTEX BREAKDOWN OVER A SHARP LEADING-EDGE DELTA WING A Thesis by IAN KENNETH MAYNARD Approved as to style and content by: Cyrus Ostowar (Chairman of Committee) Stan J Miley (M er...
TEMPEST Simulations of Collisionless Damping of Geodesic-Acoustic Mode in Edge Plasma Pedestal
Xu, X Q; Xiong, Z; Nevins, W M; McKee, G R
2007-05-30T23:59:59.000Z
The fully nonlinear (full-f) 4D TEMPEST gyrokinetic continuum code produces frequency, collisionless damping of GAM and zonal flow with fully nonlinear Boltzmann electrons for the inverse aspect ratio {epsilon}-scan and the tokamak safety factor q-scan in homogeneous plasmas. The TEMPEST simulation shows that GAM exists in edge plasma pedestal for steep density and temperature gradients, and an initial GAM relaxes to the standard neoclassical residual, rather than Rosenbluth-Hinton residual due to the presence of ion-ion collisions. The enhanced GAM damping explains experimental BES measurements on the edge q scaling of the GAM amplitude.
Linearly polarized remote-edge luminescence in GaSe nanoslabs
Tang, Yanhao; Mandal, Krishna C; McGuire, John A; Lai, Chih-Wei
2015-01-01T23:59:59.000Z
We report highly linearly polarized remote luminescence that emerges at the cleaved edges of nanoscale gallium selenide slabs tens of micrometers away from the optical excitation spot. The remote-edge luminescence (REL) measured in the reflection geometry has a degree of linear polarization above 0.90, with polarization orientation pointing toward the photoexcitation spot. The REL is dominated by an index-guided optical mode that is linearly polarized along the crystalline $c$-axis. This luminescence is from out-of-plane dipoles that are converted from in-plane dipoles through a spin-flip process at the excitation spot.
Study on higher harmonic suppression using edge filter and polished Si wafer
Gupta, R. K., E-mail: rkg@rrcat.gov.in; Singh, Amol, E-mail: rkg@rrcat.gov.in; Modi, Mohammed H., E-mail: rkg@rrcat.gov.in; Lodha, G. S., E-mail: rkg@rrcat.gov.in [X-ray Optics Section, ISU Division, Raja Ramanna Centre for Advanced Technology, Indore-452013 (India)
2014-04-24T23:59:59.000Z
Higher harmonics contamination is a severe problem in synchrotron beamlines where grating monochromators are used. In these beamlines, absorption edge filters and critical angle mirrors are used to suppress the harmonic contaminations. In the present study, carried out using Indus-1 reflectivity beamline, a harmonic suppression characteristic of Al edge filter and polished silicon wafer are determined. It is found that the Al filter suppresses higher harmonics in 2–7% range whereas the polished silicon wafer can suppress the higher harmonics below 1%. The results of comparative study are discussed.
Estimating Dual-scale Properties of Glossy Surfaces from Step-edge Lighting Chun-Po Wang
Keinan, Alon
-edge illumination from a pla- nar sample of a surface to estimate both the BRDF and the statistics of meso-scale
52 SE Biology, Vol. 56, No. 1, January, 2009 INVITED RESEARCH PAPER
Everhart, Sydney E.
country located in central Kansas on the edge of the Flint Hills. I enjoyed hunting, fishing, and outdoor 1958 I was part of a trail crew clearing trails along the road to Elk Summit Guard Station. Snow
u:\\designs\\edge_detector\\documentation\\ How ED and ED48 Work-Rev2.doc
and each can hold four 8-bit words. Eight-bits limits the leading edges to 255 and less for transitions in three groups. The first group (A) looks for a specific pattern starting in bits 9-6, the second group (B) looks at bits 5-2 and the third group (C) looks at bits 1-0. The exact pattern
Leading Edge Flow Structure of a Dynamically Pitching NACA 0012 Airfoil
Pruski, Brandon
2012-11-27T23:59:59.000Z
The leading edge flow structure of the NACA 0012 airfoil is experimentally investigated under dynamic stall conditions (M = 0.1; ? = 16.7?, 22.4?; Rec = 1× 10^6) using planar particle image velocimetry. The airfoil was dynamically pitched about...
Banerjee, Soumya Jyoti; Roy, Soumen
2014-01-01T23:59:59.000Z
There have been many studies on malicious targeting of network nodes using degree, betweenness etc. We propose a new network metric, edge proximity, ${\\cal P}_e$, which demonstrates the importance of specific edges in a network, hitherto not captured by existing network metrics. Effects of removing edges with high ${\\cal P}_e$ might initially seem inconspicuous but is eventually shown to be very harmful for the network. When compared to existing strategies, removal of edges by ${\\cal P}_e$, leads to remarkable increase of diameter and average path length in real and random networks till the first disconnection and beyond. ${\\cal P}_e$ can be consistently used to rupture the network into two nearly equal parts, thus presenting a very potent strategy to greatly harm a network. Targeting by ${\\cal P}_e$ causes notable efficiency loss in US and European power grid. ${\\cal P}_e$ identifies proteins with essential cellular functions in protein-protein interaction networks. It pinpoints regulatory neural connections...
The Blob Code is Competitive with EdgeSets in Genetic Algorithms for the Minimum
Julstrom, Bryant A.
with those of, a GA that encodes spanning trees as edge-sets on Euclidean instances of the minimum rout- ing Spanning Tree Problem Bryant A. Julstrom Department of Computer Science St. Cloud State University St. Cloud, MN, 56301 USA julstrom@stcloudstate.edu ABSTRACT Among the many codings of spanning trees
Paris-Sud XI, Université de
1 EX/P4-1 Hydrocarbon Characteristics in Fusion Edge Plasmas from Electron- Molecule and Ion proceeding in the volume before and at the wall. Surface processes involving hydrocarbons and their ions, which are probable vacuum contaminants in plasma devices, and the role of hydrocarbon chemistry
Edge stress intensity functions in 3-D anisotropic composites Zohar Yosibash a,*, Netta Omer a
Yosibash, Zohar
a , Monique Dauge b a Pearlstone Center for Aeronautical Studies, Department of Mechanical Engineering, Ben of a general edge) is of major engineering inter- est. The mathematical complexity of the 3-D anisotropic), nettao@bgu.ac.il (N. Omer), Monique.Dauge@univ-rennes1.fr (M. Dauge). www
Dileepkumar, Ananth
2014-08-14T23:59:59.000Z
The KnifeEdge Scanning Microscope (KESM) enables imaging of an entire mouse brain at sub-micrometer resolution. The data from KESM can be used in the reconstruction of neuronal and vascular structures in the mouse brain. Tracing the vascular network...
he edge of a torn plastic sheet forms a complex three-dimensional fractal
Texas at Austin. University of
T he edge of a torn plastic sheet forms a complex three-dimensional fractal shape. We have found to the generation of characteristic wavy shapes. We used rectangular plastic sheets pulled from the sides (in the y produce an irreversible plastic deforma- tion of the sheet and, as they are relieved, the deformed sheet
Leading Edge 204 Cell 141, April 16, 2010 2010 Elsevier Inc.
Zewail, Ahmed
Leading Edge Commentary 204 Cell 141, April 16, 2010 Â©2010 Elsevier Inc. The world goes through with the first Nobel Prizes in 1901. Science and technology played a pivotal role in this progress. In the 1990s with the creation of the European Union (EU), and China, Japan, and other so-called Asian Tigers assumed a major
On Clustering on Graphs with Multiple Edge Types Matthew Rocklin Ali Pinar
Pinar, Ali
the multi-dimensional space into a single dimension (e.g., finding aggregate edge weights), as well of the traditional clustering problem, we have to deal with a space of clusterings. Reducing the multi-dimensional space into a single dimension poses significant challenges. At the same time, the multi
The Green's function BEM for bimaterial solids applied to edge stress concentration problems
Denda, Mitsunori "Mitch"
The Green's function BEM for bimaterial solids applied to edge stress concentration problems M of the line forces and dislocation dipoles over its boundary. The fundamental solutions used are the Green continuity conditions there are automatically satisfied by the Green's functions. The BEM will be applied
Low Velocity Boron Micro-Pellet Injector For Edge And Core Impurity Transport Measurements
1 Low Velocity Boron Micro-Pellet Injector For Edge And Core Impurity Transport Measurements H. W, Baltimore, Maryland 21218 Abstract A simple Low Velocity Boron Micro-Pellet Injector has been under High velocity, pneumatic, pellet injection systems are applied routinely for injecting frozen pellets
H e a v y o i l 1116 The Leading Edge September 2008
H e a v y o i l 1116 The Leading Edge September 2008 Modeling studies of heavy oil--in between solid and fluid properties Rocks filled with heavy oil do not comply with established theories for porous media. Heavy oils demonstrate a blend of both purely viscous and purely elastic properties, also
H e a v y o i l 1108 The Leading Edge September 2008
H e a v y o i l 1108 The Leading Edge September 2008 Seismic properties of heavy oils--measured data Seismic techniques hold great potential for characterization and recovery monitoring of heavy oil reservoirs. However, to be more effective, we must understand the seismic properties of the heavy oils
1340 The Leading Edge October 2008 SAGE celebrates 25 years of learning geophysics by
1340 The Leading Edge October 2008 SAGE celebrates 25 years of learning geophysics by doing geophysics The increasing world demand and record-high costs for energy and mineral resources, along and educators we must seriously ask if our geophysics pipeline can adequately address this crisis. One program
Near-band edge optical properties of exfoliated h-BN layers , J. Barjon
Near-band edge optical properties of exfoliated h-BN layers J. Loayza 1,2 , J. Barjon 2 , A when it is supported by a h-BN film, in particular when mechanically exfoliated from h-BN crystallites layers have been obtained by mechanically exfoliating small crystallites. Exfoliated flakes were reported
Implementing the Render Cache and the Edge-and-Point Image On Graphics Hardware
Keinan, Alon
Implementing the Render Cache and the Edge-and-Point Image On Graphics Hardware Edgar Vel University Bruce Walter Program of Computer Graphics Cornell University Kavita Bala Department of Computer these techniques by utilizing programmable graphics process- ing units (GPUs) to achieve better framerates while
Transition-edge sensor with enhanced electrothermal feedback for cryogenic particle detection
Nam, Sae Woo (Palo Alto, CA); Cabrera, Blas (Stanford, CA)
2001-01-01T23:59:59.000Z
A superconducting transition-edge sensor with an electrothermal-feedback circuit, a heat sink thermally coupled thereto, a bias-feedback circuit electrically coupled with the electrothermal feedback circuit, and a current sensor electrically coupled with the bias-feedback circuit and inductively coupled with the electrothermal-feedback circuit.
Nunes, O.A.C.
1985-09-15T23:59:59.000Z
The influence of a strong laser field on the optical absorption edge of a direct-gap magnetic semiconductor is considered. It is shown that as the strong laser intensity increases the absorption coefficient is modified so as to give rise to an absorption tail below the free-field forbidden gap. An application is made for the case of the EuO.
Edge preserving orientation adaptive filtering P. Bakker, L.J. van Vliet, P.W. Verbeek
van Vliet, Lucas J.
Introduction Noise, which is present in every real world image, hampers manual interpretation by human experts able filters [2]. Edges between domains are important features for the interpretation of images images. The natural images are seismic im ages, which are narrow banded and contain layered structures
Edge preserving orientation adaptive filtering P. Bakker, L.J. van Vliet, P.W. Verbeek
van Vliet, Lucas J.
Introduction Noise, which is present in every real world image, hampers manual interpretation by human experts- able filters [2]. Edges between domains are important features for the interpretation of images images. The natural images are seismic im- ages, which are narrow banded and contain layered structures
Living on the Edge: Minimizing the Impact of Development along Rincon Creek
Fay, Noah
are the largest single threat to natural areas in the Western United States. In Tucson, Arizona, protected natural by protected natural areas, the Rincon Valley serves as habitat and a movement conduit for many Sonora the impact of development on natural areas at the urban-wild land edge are becoming increasingly important
University of Washington Focus the Nation Notes: Science on the cutting edge panel discussion
Rigor, Ignatius G.
University of Washington Focus the Nation 1/31/2008 Notes: Science on the cutting edge panel that was not coincident with a loss of ice, and this has led scientists to look at other factors that could impact sea-ice loss. One factor that has been recently detailed via satellite and ice-buoy information is the movement
Interpatch movement and edge effects: the role of behavioral responses to the landscape matrix
Cronin, James T.
are greater within a matrix composed of the introduced grass smooth brome (Bromus inermis) than a mudflat-plant patches (prairie cordgrass; Spartina pectinata) bordered by mudflat, but not in patches bordered by tracking the individual movements of planthoppers released at the edge of brome- and mudflat- bordered
Edge behaviour in a minute parasitic wasp John D. Reeve1
Cronin, James T.
of patches of its host plant prairie cordgrass (Spartina pectinata) interspersed within a matrix of mudflat, smooth brome (Bromus inermis) and native grasses. Two edge types are common in this system, cordgrass-mudflat substrates (cordgrass, brome, mudflat). The diffusive and advective components of move- ment were
A mimetic finite difference method for the Stokes problem with elected edge bubbles
Lipnikov, K [Los Alamos National Laboratory; Berirao, L [DIPARTMENTO DI MATERMATICA
2009-01-01T23:59:59.000Z
A new mimetic finite difference method for the Stokes problem is proposed and analyzed. The unstable P{sub 1}-P{sub 0} discretization is stabilized by adding a small number of bubble functions to selected mesh edges. A simple strategy for selecting such edges is proposed and verified with numerical experiments. The discretizations schemes for Stokes and Navier-Stokes equations must satisfy the celebrated inf-sup (or the LBB) stability condition. The stability condition implies a balance between discrete spaces for velocity and pressure. In finite elements, this balance is frequently achieved by adding bubble functions to the velocity space. The goal of this article is to show that the stabilizing edge bubble functions can be added only to a small set of mesh edges. This results in a smaller algebraic system and potentially in a faster calculations. We employ the mimetic finite difference (MFD) discretization technique that works for general polyhedral meshes and can accomodate non-uniform distribution of stabilizing bubbles.
Cryogenic pellet launcher adapted for controlling of tokamak plasma edge instabilities
Lang, P. T.; Cierpka, P.; Harhausen, J.; Neuhauser, J.; Wittmann, C.; Gal, K.; Kalvin, S.; Kocsis, G.; Sarkoezi, J.; Szepesi, T.; Dorner, C.; Kauke, G. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, 85748 Garching (Germany); KFKI-RMKI, EURATOM Association, P.O. Box 49, H-1525 Budapest-114 (Hungary); Fachhochschule Regensburg, Fachbereich Maschinenbau, Galgenbergstrasse 30, 93053 Regensburg (Germany)
2007-02-15T23:59:59.000Z
One of the main challenges posed recently on pellet launcher systems in fusion-oriented plasma physics is the control of the plasma edge region. Strong energy bursts ejected from the plasma due to edge localized modes (ELMs) can form a severe threat for in-vessel components but can be mitigated by sufficiently frequent triggering of the underlying instabilities using hydrogen isotope pellet injection. However, pellet injection systems developed mainly for the task of ELM control, keeping the unwanted pellet fueling minimized, are still missing. Here, we report on a novel system developed under the premise of its suitability for control and mitigation of plasma edge instabilities. The system is based on the blower gun principle and is capable of combining high repetition rates up to 143 Hz with low pellet velocities. Thus, the flexibility of the accessible injection geometry can be maximized and the pellet size kept low. As a result the new system allows for an enhancement in the tokamak operation as well as for more sophisticated experiments investigating the underlying physics of the plasma edge instabilities. This article reports on the design of the new system, its main operational characteristics as determined in extensive test bed runs, and also its first test at the tokamak experiment ASDEX Upgrade.
NONAXISYMMETRIC ENDWALL CONTOURING AND LEADING EDGE MODIFICATIONS ON TURBINE NOZZLE GUIDE VANES
Guiltinan, Mark
PENNSTATE _ NONAXISYMMETRIC ENDWALL CONTOURING AND LEADING EDGE MODIFICATIONS ON TURBINE NOZZLE:00 am 228 Hammond Building "The three main sources of the total pressure deficit in a turbine stage to endwall boundary layer in a turbine passage may represent about one third of the total loss measured
Edge-Enriched Graphitic Anodes by KOH Activation for Higher Rate Capability Lithium Ion Batteries
UG-36 Edge-Enriched Graphitic Anodes by KOH Activation for Higher Rate Capability Lithium Ion Batteries D. Zakhidov,1,2 R. Sugamata,3 T. Yasue,3 T. Hayashi,3 Y. A. Kim,3 and M. Endo4 1 for Exotic Nanocarbons (JST), Shinshu University, Nagano, Japan\\ Natural graphite is the most commercially
Shapefile Overlay Using a Doubly-Connected Edge List Phil Katz and Stephen St.Vincent
Danner, Andrew
Shapefile Overlay Using a Doubly-Connected Edge List Phil Katz and Stephen St.Vincent Swarthmore easily perform shapefile overlay operations: in- tersection, difference, and union. Our algorithm runs) Figure 1: Examples of shapefile overlays. (a) The original polygons in set S. Here, we have two over
absorption near-edge spectroscopy: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
absorption near-edge spectroscopy First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Effect of...
absorption near-edge structure: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
absorption near-edge structure First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Effect of Intermolecular...
absorption pre-edge structures: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
absorption pre-edge structures First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Temperature dependence...
Living on the Edge: Agriculture in Periurban Mexico City Andy Wanning
Living on the Edge: Agriculture in Periurban Mexico City Andy Wanning Spring 2014 Capstone M.S. Sustainability Management Isla Urbana installs rainwater harvesting systems in and around Mexico City so that people aren't forced to get water via... Sistema Biobolsa installs biodigesters throughout Mexico so that
Spectrally narrowed leaky waveguide edge emission and transient electrluminescent dynamics of OLEDs
Zhengqing, Gan
2010-05-16T23:59:59.000Z
In summary, there are two major research works presented in this dissertation. The first research project (Chapter 4) is spectrally narrowed edge emission from Organic Light Emitting Diodes. The second project (Chapter 5) is about transient electroluminescent dynamics in OLEDs. Chapter 1 is a general introduction of OLEDs. Chapter 2 is a general introduction of organic semiconductor lasers. Chapter 3 is a description of the thermal evaporation method for OLED fabrication. The detail of the first project was presented in Chapter 4. Extremely narrowed spectrum was observed from the edge of OLED devices. A threshold thickness exists, above which the spectrum is narrow, and below which the spectrum is broad. The FWHM of spectrum depends on the material of the organic thin films, the thickness of the organic layers, and length of the OLED device. A superlinear relationship between the output intensity of the edge emission and the length of the device was observed, which is probably due to the misalignment of the device edge and the optical fiber detector. The original motivation of this research is for organic semiconductor laser that hasn't been realized due to the extremely high photon absorption in OLED devices. Although we didn't succeed in fabricating an electrically pumped organic laser diode, we made a comprehensive research in edge emission of OLEDs which provides valuable results in understanding light distribution and propagation in OLED devices. Chapter 5 focuses on the second project. A strong spike was observed at the falling edge of a pulse, and a long tail followed. The spike was due to the recombination of correlated charge pair (CCP) created by trapped carriers in guest molecules of the recombination zone. When the bias was turned off, along with the decreasing of electric field in the device, the electric field induced quenching decreases and the recombination rate of the CCP increases which result in the spike. This research project provides a profound understanding of the EL dynamics of OLED, and the theoretical model can fit and explain the experiment data quite well. For the edge emission, we focused on the spectrum and the relative intensity of the edge emission. In the future, more research can be done on the comparison of the intensity between the total edge emission and the surface emission which will give us a sense what fraction of light was trapped in the device. Micro structures can be integrated into the OLED such as DFB and DBR, the character of edge emission should be very interesting. For the transient spike, the CCP model can give a good explanation. But in the model, the effect of the electric field change is not included, because from the start point (t=0), we assume the mobility of carriers is a constant. If we consider the details of the change of the electric field, then when turning of the bias, the decrease of the electric field results in decrease of the carrier mobility and the dissociation rate. If we can add the electric field effect into the model, the whole theory will be more convincing.
Ghosh, Sandip
Edge-emission electroluminescence study of as-grown vertical-cavity surface-emitting laser 22 April 2000 We report polarized edge- and front-emission electroluminescence studies on red on pieces of as-grown wafers using indiumtinoxide-coated glass electrodes. The front-emission spectra
Curvature and Tachibana numbers
Stepanov, Sergey E [Finance Academy under the Government of the Russian Federation, Moscow (Russian Federation)
2011-07-31T23:59:59.000Z
The aim of this paper is to define the rth Tachibana number t{sub r} of an n-dimensional compact oriented Riemannian manifold as the dimension of the space of conformally Killing r-forms, for r=1,2,...,n-1. We also describe properties of these numbers, by analogy with properties of the Betti numbers b{sub r} of a compact oriented Riemannian manifold. Bibliography: 25 titles.
Wang Fei; Zhao Xuezeng [School of Mechanical and Electronic Engineering, Harbin Institute of Technology, Harbin 150001 (China); Li Ning [Shanghai Second Polytechnic University, Shanghai 201209 (China)
2010-10-15T23:59:59.000Z
We introduce a multiscale characterization method for line edge roughness (LER) based on redundant second generation wavelet transform. This method involves decomposing LER characteristics into independent bands with different spatial frequency components at different scales, and analyzing the reconstructed signals to work out the roughness exponent, the spatial frequency distribution characteristics, as well as the rms value. The effect of noise can be predicted using detailed signals in the minimum space of scale. This method was applied to numerical profiles for validation. Results show that according to the line edge profiles with similar amplitudes, the roughness exponent R can effectively reflect the degree of irregularity of LER and intuitively provide information on LER spatial frequency distribution.
Leung, Kevin
2015-01-01T23:59:59.000Z
The applied potential governs lithium-intercalation and electrode passivation reactions in lithium ion batteries, but are challenging to calibrate in condensed phase DFT calculations. In this work, the "anode potential" of charge-neutral lithium-intercalated graphite (LiC(6)) with oxidized edge planes is computed as a function of Li-content n(Li)) at edge planes, using ab initio molecular dynamics (AIMD), a previously introduced Li+ transfer free energy method, and the experimental Li+/Li(s) value as reference. The voltage assignments are corroborated using explicit electron transfer from fluoroethylene carbonate radical anion markers. PF6- is shown to decompose electrochemically (i.e., not just thermally) at low potentials imposed by our voltage calibration technique. We demonstrate that excess electrons reside in localized states-in-the-gap in the organic carbonate liquid region, which is not semiconductor-like (band-state-like) as widely assumed in the literature.
SXR-XUV Diagnostics for Edge and Core of Magnetically Confined Plasmas
Stutman, Dan [Johns Hopkins University
2014-09-10T23:59:59.000Z
The present report summarizes the results obtained during a one-year extension of DoE grant “SXR-XUV Diagnostics for Edge and Core of Magnetically Confined Plasmas”, at Johns Hopkins University, aimed at completing the development of a new type of magnetic fusion plasma diagnostic, the XUV Transmission Grating Imaging Radiometer (TGIR). The TGIR enables simultaneous spatially and spectrally resolved measurements of the XUV/VUV radiated power from impurities in fusion plasmas, with high speed. The instrument was successfully developed and qualified in the laboratory and in experiments on a tokamak. Its future applications will be diagnostic of the impurity content and transport in the divertor and edge of advanced magnetic fusion experiments, such as NSTX Upgrade.
Improved DESI-MS Performance using Edge Sampling and aRotational Sample Stage
Kertesz, Vilmos [ORNL; Van Berkel, Gary J [ORNL
2008-01-01T23:59:59.000Z
The position of the surface to be analyzed relative to the sampling orifice or capillary into the mass spectrometer has been known to dramatically affect the observed signal levels in desorption electrospray ionization mass spectrometry (DESIMS). In analyses of sample spots on planar surfaces, DESI-MS signal intensities as much as five times greater were routinely observed when the bottom of the sampling capillary was appropriately positioned beneath the surface plane ( edge sampling") compared to when the capillary just touched the surface. To take advantage of the optimum "edge sampling" geometry and to maximize the number of samples that could be analyzed in this configuration, a rotational sample stage was integrated into a typical DESI-MS setup. The rapid quantitative determination of caffeine in two diet sport drinks (Diet Turbo Tea, Speed Stack Grape) spiked with an isotopically labeled internal standard demonstrated the utility of this approach.
On gas desorption from the tokamak first wall during edge localized modes
Marenkov, E. D., E-mail: edmarenkov@gmail.com [National Nuclear Research University Moscow Engineering and Physics Institute (Russian Federation); Smirnov, R. D.; Krasheninnikov, S. I. [University of California, San Diego (United States)] [University of California, San Diego (United States)
2013-11-15T23:59:59.000Z
The effect of gas desorption from the tokamak first wall on the pedestal recovery in the H-mode after an edge-localized-mode burst is considered. Results of FACE code simulations of hydrogen desorption from a beryllium wall are presented. It is found that the wall has a significant effect on plasma processes only at sufficiently low temperatures (of about 400 K), which agrees with qualitative estimates obtained earlier in the zero-dimensional approximation.
Knife-Edge Scanning Microscope Mouse Brain Atlas In Vector Graphics For Enhanced Performance
Choi, Jinho
2013-07-17T23:59:59.000Z
KNIFE-EDGE SCANNING MICROSCOPE MOUSE BRAIN ATLAS IN VECTOR GRAPHICS FOR ENHANCED PERFORMANCE A Thesis by JINHO CHOI Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements for the degree... of MASTER OF SCIENCE Chair of Committee, Yoonsuck Choe Committee Members, John Keyser Louise Abbott Department Head, Duncan M. \\Hank" Walker August 2013 Major Subject: Computer Science Copyright 2013 Jinho Choi ABSTRACT The microstructure...
In situ tomography of femtosecond optical beams with a holographic knife-edge
Strohaber, James; Kaya, G; N, Kay; Hart, Nathan; Kolomenskii, Alexander; Paulus, Gerhard; Schuessler, Hans
2011-07-18T23:59:59.000Z
? that are mechanically difficult or impossible to reproduce. We test our method by holographically knife-edging and tomographically reconstructing both continuous wave and broadband radiation in transverse optical modes. ?2011 Optical Society of America OCIS codes... the sign of the angular dispersion causing the dispersed broadband beam to exhibit a zero amount of spatial dispersion at the position of the second grating [13]. At all other positions within the setup, except at the position of the first grating...
Deriving the redshift of distant galaxies with Gamma-Ray Burst transient edges
Le Floc'h, E; Mirabel, I F
2002-01-01T23:59:59.000Z
Cosmological Gamma-Ray Bursts (GRBs) offer a unique perspective to probe the evolution of distant galaxies. We discuss one of the multiple benefits of this approach, i.e. the detection of transient edges in the GRB prompt phase emission. These absorption features can be used to directly derive the redshift of GRBs and their host galaxies without the need of any optical spectroscopic follow-up.
LIGHT SUBGRAPHS IN PLANAR GRAPHS OF MINIMUM DEGREE 4 AND EDGE-DEGREE 9
Mohar, Bojan
LIGHT SUBGRAPHS IN PLANAR GRAPHS OF MINIMUM DEGREE 4 AND EDGE-DEGREE 9 B. MOHAR , R. SKREKOVSKI vertices of degree 4 are adjacent. A graph H is light in G if there is a constant w such that every graph is w. Then we also write w(H) w. It is proved that the cycle Cs is light if and only if 3 s 6, where