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1

Nonperturbative Type I-I' String Theory  

E-Print Network [OSTI]

We propose a nonperturbative framework for the O(32) type I open and closed string theory. The short distance degrees of freedom are bosonic and fermionic hermitian matrices belonging respectively to the adjoint and fundamental representations of the special unitary group SU(N). We identify a closed matrix algebra at finite N which corresponds to the Lorentz, gauge, and supersymmetry algebras of the large N continuum limit. The planar reduction of our matrix theory coincides with the low energy spacetime effective action of the d=10 type I O(32) unoriented open and closed string theory. We show that matrix T-duality transformations can yield a nonperturbative framework for the T-dual type I' closed string theory with 32 D8branes. We show further that under a strong-weak coupling duality transformation the large N reduced action coincides with the low energy spacetime effective action of the d=10 heterotic string, an equivalence at leading order in the inverse string tension and with either gauge group Spin(32)/Z2 or E8xE8. Our matrix formalism has the potential of providing a nonperturbative framework encapsulating all of the weak coupling limits of M theory.

Shyamoli Chaudhuri

2005-07-24T23:59:59.000Z

2

Space-Efficient Framework for Top-k String Retrieval Problems (extended abstract)  

E-Print Network [OSTI]

strings for a given query pattern P. This involves somewhat more advanced query functionality than the usual pattern matching, as some notion of “most relevant” is involved. In information retrieval literature, this task is best achieved by using inverted... compared well with inverted indexes in their space utilization but also provided query functionality for arbitrary patterns. Since then, designing succinct or compressed data structures for text problems has been a thriving field of research with many...

Hon, Wing-Kai; Shah, Rahul; Vitter, Jeffrey Scott

2009-01-01T23:59:59.000Z

3

Duality Phase Transition in Type I String Theory  

E-Print Network [OSTI]

We show that the duality phase transition in the unoriented type I theory of open and closed strings is_first order_. The order parameter is the semiclassical approximation to the heavy quark-antiquark potential at finite temperature, extracted from the covariant off-shell string amplitude with Wilson loop boundaries wrapped around the Euclidean time direction. Remarkably, precise calculations can be carried out on either side of the phase boundary at the string scale T_C = 1/2\\pi \\alpha^{'1/2} by utilizing the T-dual, type IB and type I', descriptions of the short string gas of massless gluon radiation. We will calculate the change in the duality transition temperature in the presence of an electromagnetic background field.

Shyamoli Chaudhuri

2005-09-09T23:59:59.000Z

4

D-brane Instantons in Type II String Theory  

SciTech Connect (OSTI)

We review recent progress in determining the effects of D-brane instantons in N=1 supersymmetric compactifications of Type II string theory to four dimensions. We describe the abstract D-brane instanton calculus for holomorphic couplings such as the superpotential, the gauge kinetic function and higher fermionic F-terms. This includes a discussion of multi-instanton effects and the implications of background fluxes for the instanton sector. Our presentation also highlights, but is not restricted to the computation of D-brane instanton effects in quiver gauge theories on D-branes at singularities. We then summarize the concrete consequences of stringy D-brane instantons for the construction of semi-realistic models of particle physics or SUSY-breaking in compact and non-compact geometries.

Blumenhagen, Ralph; /Munich, Max Planck Inst.; Cvetic, Mirjam; /Pennsylvania U.; Kachru, Shamit; /Stanford U., Phys. Dept. /SLAC; Weigand, Timo; /SLAC

2009-06-19T23:59:59.000Z

5

Warped Tachyonic Inflation in Type IIB Flux Compactifications and the Open-String Completeness Conjecture  

E-Print Network [OSTI]

We consider a cosmological scenario within the KKLT framework for moduli stabilization in string theory. The universal open string tachyon of decaying non-BPS D-brane configurations is proposed to drive eternal topological inflation. Flux-induced `warping' can provide the small slow-roll parameters needed for successful inflation. Constraints on the parameter space leading to sufficient number of e-folds, exit from inflation, density perturbations and stabilization of the Kahler modulus are investigated. The conditions are difficult to satisfy in Klebanov-Strassler throats but can be satisfied in T^3 fibrations and other generic Calabi-Yau manifolds. This requires large volume and magnetic fluxes on the D-brane. The end of inflation may or may not lead to cosmic strings depending on the original non-BPS configuration. A careful investigation of initial conditions leading to a phenomenologically viable model for inflation is carried out. The initial conditions are chosen on the basis of Sen's open string completeness conjecture. We find time symmetrical bounce solutions without initial singularities for k=1 FRW models which are correlated with an inflationary period. Singular big-bang/big-crunch solutions also exist but do not lead to inflation. There is an intriguing correlation between having an inflationary universe in 4 dimensions and 6 compact dimensions or a big-crunch singularity and decompactification.

Daniel Cremades; Fernando Quevedo; Aninda Sinha

2005-11-14T23:59:59.000Z

6

An Open String Landscape  

E-Print Network [OSTI]

The effect of fluxes on open string moduli is studied by analyzing the constraints imposed by supersymmetry on D-branes in type IIB flux backgrounds. We show that generically the conditions of supersymmetry cannot be maintained when moving along the geometrical moduli space of the brane, so that open string moduli are lifted. We argue that there is a disconnected and discrete set of supersymmetric solutions to the open string equations of motion, which extends the familiar closed string landscape to the open string sector.

Jaume Gomis; Fernando Marchesano; David Mateos

2005-11-16T23:59:59.000Z

7

Engineering of Quantum Hall Effect from Type IIA String Theory on The K3 Surface  

E-Print Network [OSTI]

Using D-brane configurations on the K3 surface, we give six dimensional type IIA stringy realizations of the Quantum Hall Effect (QHE) in 1+2 dimensions. Based on the vertical and horizontal lines of the K3 Hodge diamond, we engineer two different stringy realizations. The vertical line presents a realization in terms of D2 and D6-branes wrapping the K3 surface. The horizontal one is associated with hierarchical stringy descriptions obtained from a quiver gauge theory living on a stack of D4-branes wrapping intersecting 2-spheres embedded in the K3 surface with deformed singularities. These geometries are classified by three kinds of the Kac-Moody algebras: ordinary, i.e finite dimensional, affine and indefinite. We find that no stringy QHE in 1+2 dimensions can occur in the quiver gauge theory living on intersecting 2-spheres arranged as affine Dynkin diagrams. Stringy realizations of QHE can be done only for the finite and indefinite geometries. In particular, the finite Lie algebras give models with fractional filling fractions, while the indefinite ones classify models with negative filling fractions which can be associated with the physics of holes in the graphene.

Adil Belhaj; Antonio Segui

2010-07-02T23:59:59.000Z

8

Combined Retrieval, Microphysical Retrievals and Heating Rates  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Microphysical retrievals and heating rates from the AMIE/Gan deployment using the PNNL Combined Retrieval.

Feng, Zhe

9

Combined Retrieval, Microphysical Retrievals and Heating Rates  

SciTech Connect (OSTI)

Microphysical retrievals and heating rates from the AMIE/Gan deployment using the PNNL Combined Retrieval.

Feng, Zhe

2013-02-22T23:59:59.000Z

10

Finite Temperature Gases of Fermionic Strings  

E-Print Network [OSTI]

We show that in the absence of a Ramond-Ramond sector both the type IIA and type IIB free string gases have a thermal instability due to low temperature tachyon modes. The gas of free IIA strings undergoes a thermal duality transition into a gas of free IIB strings at the self-dual temperature. The free heterotic string gas is a tachyon-free ensemble with gauge symmetry SO(16)$\\times$SO(16) in the presence of a timelike Wilson line background. It exhibits a holographic duality relation undergoing a self-dual phase transition with positive free energy and positive specific heat. The type IB open and closed string ensemble is related by thermal duality to the type I' string ensemble. We identify the order parameter for the Kosterlitz-Thouless phase transition from a low temperature gas of short open strings to a high temperature long string phase at or below T_C. Note Added (Sep 2005).

Shyamoli Chaudhuri

2005-09-12T23:59:59.000Z

11

Classical string in curved backgrounds  

SciTech Connect (OSTI)

The Mathisson-Papapetrou method is originally used for derivation of the particle world line equation from the covariant conservation of its stress-energy tensor. We generalize this method to extended objects, such as a string. Without specifying the type of matter the string is made of, we obtain both the equations of motion and boundary conditions of the string. The world sheet equations turn out to be more general than the familiar minimal surface equations. In particular, they depend on the internal structure of the string. The relevant cases are classified by examining canonical forms of the effective 2-dimensional stress-energy tensor. The case of homogeneously distributed matter with the tension that equals its mass density is shown to define the familiar Nambu-Goto dynamics. The other three cases include physically relevant massive and massless strings, and unphysical tachyonic strings.

Vasilic, Milovan; Vojinovic, Marko [Institute of Physics, P. O. Box 57, 11001 Belgrade (Serbia and Montenegro)

2006-06-15T23:59:59.000Z

12

String Phenomenology  

E-Print Network [OSTI]

Following Dyson's analogy between the quantum field theory and the 19th-century chemistry-both explain how but not why-one could also establish an analogy between atomic physics and string theory. Atomic physics was needed to answer the question why in chemistry, string theory is trying to answer the question why in the standard model. This attempt is very briefly reviewed in this talk. After discussing the phenomenological aspects of string theory, the study of soft terms is emphasized as a possible connection between theory and experiment. Special attention is paid to the issues of flavor changing neutral currents, loop effects, charge and color breaking minima, and M-theory versus weakly coupled string theory.

C. Muńoz

1998-02-23T23:59:59.000Z

13

Phase 2, Solid waste retrieval strategy  

SciTech Connect (OSTI)

Solid TRU retrieval, Phase 1 is scheduled to commence operation in 1998 at 218W-4C-T01 and complete recovery of the waste containers in 2001. Phase 2 Retrieval will recover the remaining buried TRU waste to be retrieved and provide the preliminary characterization by non-destructive means to allow interim storage until processing for disposal. This document reports on researching the characterization documents to determine the types of wastes to be retrieved and where located, waste configurations, conditions, and required methods for retrieval. Also included are discussions of wastes encompassed by Phase 2 for which there are valid reasons to not retrieve.

Johnson, D.M.

1994-09-29T23:59:59.000Z

14

String bit models for superstring  

SciTech Connect (OSTI)

The authors extend the model of string as a polymer of string bits to the case of superstring. They mainly concentrate on type II-B superstring, with some discussion of the obstacles presented by not II-B superstring, together with possible strategies for surmounting them. As with previous work on bosonic string work within the light-cone gauge. The bit model possesses a good deal less symmetry than the continuous string theory. For one thing, the bit model is formulated as a Galilei invariant theory in (D {minus} 2) + 1 dimensional space-time. This means that Poincare invariance is reduced to the Galilei subgroup in D {minus} 2 space dimensions. Naturally the supersymmetry present in the bit model is likewise dramatically reduced. Continuous string can arise in the bit models with the formation of infinitely long polymers of string bits. Under the right circumstances (at the critical dimension) these polymers can behave as string moving in D dimensional space-time enjoying the full N = 2 Poincare supersymmetric dynamics of type II-B superstring.

Bergman, O.; Thorn, C.B.

1995-12-31T23:59:59.000Z

15

String Gas Baryogenesis  

E-Print Network [OSTI]

We describe a possible realization of the spontaneous baryogenesis mechanism in the context of extra-dimensional string cosmology and specifically in the string gas scenario.

G. L. Alberghi

2010-02-19T23:59:59.000Z

16

Phenomenology from the Landscape of String Vacua  

E-Print Network [OSTI]

This article is the author's PhD thesis. After a review of string vacua obtained through compactification (with and wothout fluxes), it presents and describes various aspects of the Landscape of string vacua. At first it gives an introduction and an overview of the statistical study of the set of four dimensional string vacua, giving the detailed study of one corner of this set (G2-holonomy compactifications of M-theory). Then it presents the ten dimensional approach to string vacua, concentrating on the ten dimensional description of the Type IIA flux vacua. Finally it gives two examples of models having some interesting and characteristic phenomenological features, and that belong to two different corners of the Landscape: warped compactifications of Type IIB String Theory and M-theory compactifications on G2-holonomy manifolds.

Roberto Valandro

2008-07-04T23:59:59.000Z

17

Fluid Mechanics of Strings  

E-Print Network [OSTI]

We consider conserved currents in an interacting network of one-dimensional objects (or strings). Singular currents localized on a single string are considered in general, and a formal procedure for coarse-graining over many strings is developed. This procedure is applied to strings described by the Nambu-Goto action such as cosmic strings. In addition to conserved currents corresponding to the energy-momentum tensor, we consider an antisymmetric tensor of conserved currents related to the string tangent vector. Under the assumption of local equilibrium we derive a complete set of hydrodynamic equations for strings.

Daniel Schubring; Vitaly Vanchurin

2013-06-02T23:59:59.000Z

18

Nonsingular static global string  

E-Print Network [OSTI]

A new solution for the spacetime outside the core of a U(1) static global string has been presented which is nonsingular. This is the first example of a nonsingular spacetime around a static global string.}}

A. A. Sen; N. Banerjee

2000-04-12T23:59:59.000Z

19

Drill string enclosure  

DOE Patents [OSTI]

The drill string enclosure consists of six component parts, including; a top bracket, an upper acrylic cylinder, an acrylic drill casing guide, a lower acrylic cylinder, a bottom bracket, and three flexible ducts. The upper acrylic cylinder is optional based upon the drill string length. The drill string enclosure allows for an efficient drill and sight operation at a hazardous waste site.

Jorgensen, D.K.; Kuhns, D.J.; Wiersholm, O.; Miller, T.A.

1993-03-02T23:59:59.000Z

20

Thermal Duality and the String Canonical Ensemble  

E-Print Network [OSTI]

We derive the free energies of both the closed heterotic, and the unoriented, open and closed, type I string ensembles, consistent with the thermal (Euclidean T-duality) transformations on the String/M Duality Web. A crucial role is played by a temperature dependent Wilson line wrapping Euclidean time, responsible for the spontaneous breaking of supersymmetry at finite temperature while eliminating thermal tachyons, and determined uniquely by thermal duality. Conversely, we can show that the absence of a Yang-Mills gauge sector precludes the possibility of an equilibrium type II canonical ensemble prior to the introduction of background Dbranes or fluxes. As a consistency check, we verify that our results for the string free energy always reproduce the T^{10} growth expected in the low energy field theory limits while displaying a dramatically slower T^2 growth at temperatures above the string scale. We present both the low and high temperature expansions for the one-loop heterotic and type I string free energies, results which follow from an explicit term-by-term evaluation of the modular integrals in the string mass level expansion.

Shyamoli Chaudhuri

2005-10-21T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Effect of cosmic string on spin dynamics  

E-Print Network [OSTI]

In the present paper, we have investigated the role of cosmic string on spin current and Hall electric field. Due to the background cosmic string, the modified electric field of the system generates renormalized spin orbit coupling, which induces a modified non-Abelian gauge field. The defect causes a change in the AB and AC phases appearing due to the modified electromagnetic field. In addition, for a time varying electric field we perform explicit analytic calculations to derive the exact form of spin electric field and spin current, which is defect parameter dependent and of oscillating type. Furthermore, in an asymmetric crystal within the Drude model approach we investigate the dependence of the cosmic string parameters on cosmic string induced Hall electric field.

Debashree Chowdhury; B. Basu

2014-11-07T23:59:59.000Z

22

Topics in String Phenomenology  

E-Print Network [OSTI]

We consider two questions in string ``phenomenology.'' First, are there any generic string predictions? Second, are there any general lessons which string theory suggests for thinking about low energy models, particularly in the framework of supersymmetry? Among the topics we consider are the squark and slepton spectrum, flavor symmetries, discrete symmetries including $CP$, and Peccei-Quinn symmetries. We also note that in some cases, discrete symmetries can be used to constrain the form of supersymmetry breaking.

Michael Dine

1993-09-23T23:59:59.000Z

23

Resumming the string perturbation series  

E-Print Network [OSTI]

We use the AdS/CFT correspondence to study the resummation of a perturbative genus expansion appearing in the type II superstring dual of ABJM theory. Although the series is Borel summable, its Borel resummation does not agree with the exact non-perturbative answer due to the presence of complex instantons. The same type of behavior appears in the WKB quantization of the quartic oscillator in Quantum Mechanics, which we analyze in detail as a toy model for the string perturbation series. We conclude that, in these examples, Borel summability is not enough for extracting non-perturbative information, due to non-perturbative effects associated to complex instantons. We also analyze the resummation of the genus expansion for topological string theory on local $\\mathbb P^1 \\times \\mathbb P^1$, which is closely related to ABJM theory. In this case, the non-perturbative answer involves membrane instantons computed by the refined topological string, which are crucial to produce a well-defined result. We give evidence that the Borel resummation of the perturbative series requires such a non-perturbative sector.

Alba Grassi; Marcos Marino; Szabolcs Zakany

2015-02-10T23:59:59.000Z

24

Extreme Cosmic String  

E-Print Network [OSTI]

This paper deals with the geometry of supermassive cosmic strings. We have used an approach that enforces the spacetime of cosmic strings to also satisfy the conservation laws of a cylindric gravitational topological defect, that is a spacetime kink. In the simplest case of kink number unity, the entire energy range of supermassive strings becomes then quantized so that only cylindrical defects with linear energy density $G\\mu=1/4$ (critical string) and $G\\mu=1/2$ (extreme string) are allowed to occur in this range. It has been seen that the internal spherical coordinate $\\theta$ of the string metric embedded in an Euclidean three-space also evolves on imaginary values, leading to the creation of a covering shell of broken phase that protects the core with trapped energy, even for $G\\mu=1/2$. Then the conical singularity becomes a removable horizaon singularity. We re-express the extreme string metric in the Finkelstein- McCollum standard form and remove the geodesic incompleteness by using the Kruskal technique. The z=const. sections of the resulting metric are the same as the hemispherical section of the metric of a De Sitter kink. Some physical consequences from these results, including the possibility that the extreme string drives inflation and thermal effects in its core, are also discussed.

P. F. Gonzalez-Diaz

1995-08-28T23:59:59.000Z

25

Type A Accident Investigation Board Report on the February 20, 1996, Fall Fatality at the Radioactive Waste Management Complex Transuranic Storage Area- Retrieval Enclosure, Idaho National Engineering Laboratory  

Broader source: Energy.gov [DOE]

This report is an independent product of the Type A Accident Investigation Board appointed by Tara O’Toole, M.D., M.P.H., Assistant Secretary for Environment, Safety and Health (EH-1).

26

Arenas for String Phenomenology String Phenomenology 2011, Madison  

E-Print Network [OSTI]

Arenas for String Phenomenology String Phenomenology 2011, Madison Michael Dine Department of Physics University of California, Santa Cruz August, 2011 Michael Dine Arenas for String Phenomenology #12;Possible Arenas for a String Phenomenology 1 Hierarchy problem: LHC scale physics: supersymmetry, RS, large

California at Santa Cruz, University of

27

Retrieval options study  

SciTech Connect (OSTI)

This Retrieval Options Study is part of the systems analysis activities of the Office of Nuclear Waste Isolation to develop the scientific and technological bases for radioactive waste repositories in various geologic media. The study considers two waste forms, high level waste and spent fuel, and defines various classes of waste retrieval and recovery. A methodology and data base are developed which allow the relative evaluation of retrieval and recovery costs and the following technical criteria: safety; technical feasibility; ease of retrieval; probable intact retrieval time; safeguards; monitoring; criticality; and licensability. A total of 505 repository options are defined and the cost and technical criteria evaluated utilizing a combination of facts and engineering judgments. The repositories evaluated are selected combinations of the following parameters: Geologic Media (salt, granite, basalt, shale); Retrieval Time after Emplacement (5 and 25 years); Emplacement Design (nominal hole, large hole, carbon steel canister, corrosion resistant canister, backfill in hole, nominal sleeves, thick wall sleeves); Emplacement Configuration (single vertical, multiple vertical, single horizontal, multiple horizontal, vaults; Thermal Considerations; (normal design, reduced density, once-through ventilation, recirculated ventilation); Room Backfill; (none, run-of-mine, early, 5 year delay, 25 year delay, decommissioned); and Rate of Retrieval; (same as emplacement, variably slower depending on repository/canister condition).

Not Available

1980-03-01T23:59:59.000Z

28

Twistor Strings and Supergravity  

SciTech Connect (OSTI)

Einstein gravity can be formulated in such a way that it leads to a perturbation theory about an asymmetric weak coupling limit that treats positive and negative helicities differently. The power counting rules for scattering amplitudes then suggest an interpretation in terms of a twistor string theory for gravity, with amplitudes supported on holomorphic curves in twistor space. After reviewing this formulation, I survey the recent construction of a family of new twistor string theories h are free from world-sheet anomalies and give the space-time spectra of Einstein supergravities, with second order field equations instead of the higher derivative conformal supergravities that arose from earlier twistor strings.

Abou-Zeid, Mohab [Theoretische Natuurkunde, Vrije Universiteit Brussel and The International Solvay Institutes, Pleinlaan 2, 1050 Brussels (Belgium)

2007-01-12T23:59:59.000Z

29

Singularities and Closed String Tachyons  

SciTech Connect (OSTI)

A basic problem in gravitational physics is the resolution of spacetime singularities where general relativity breaks down. The simplest such singularities are conical singularities arising from orbifold identifications of flat space, and the most challenging are spacelike singularities inside black holes (and in cosmology). Topology changing processes also require evolution through classically singular spacetimes. I briefly review how a phase of closed string tachyon condensate replaces, and helps to resolve, basic singularities of each of these types. Finally I discuss some interesting features of singularities arising in the small volume limit of compact negatively curved spaces and the emerging zoology of spacelike singularities.

Silverstein, Eva; /SLAC /Stanford U., Phys. Dept.

2006-03-17T23:59:59.000Z

30

Monitored Retrievable Storage Background  

Broader source: Energy.gov [DOE]

`The U.S. Government is seeking a site for a monitored retrievable storage facility (MRS). Employing proven technologies used in this country and abroad, the MRS will be an Integral part of the...

31

Improved freezing level retrieval  

E-Print Network [OSTI]

TRMM Microwave Imager(TMI)-based passive microwave retrieval techniques result in biased estimates of the freezing level and rainfall over the east Pacific in the Inter Tropical Convergence Zone (ITCZ). Passive microwave rainfall estimates...

Hong, Sungwook

2002-01-01T23:59:59.000Z

32

Strings at finite temperature  

SciTech Connect (OSTI)

We obtain a semiclassical evaluation of the temperature for which the free energy of the strings of spontaneously broken scalar electrodynamics vanishes. We argue that, above this temperature, these objects should play a significant physical role.

Arago C. de; Bazeia, D.; Eboli, O.J.P.; Marques, G.C.

1985-12-15T23:59:59.000Z

33

Origin of black string instability  

SciTech Connect (OSTI)

It is argued that many nonextremal black branes exhibit a classical Gregory-Laflamme (GL) instability. Why does the universal instability exist? To find an answer to this question and explore other possible instabilities, we study stability of black strings for all possible types of gravitational perturbation. The perturbations are classified into tensor-, vector-, and scalar-types, according to their behavior on the spherical section of the background metric. The vector and scalar perturbations have exceptional multipole moments, and we have paid particular attention to them. It is shown that for each type of perturbations there is no normalizable negative (unstable) modes, apart from the exceptional mode known as s-wave perturbation which is exactly the GL mode. We discuss the origin of instability and comment on the implication for the correlated-stability conjecture.

Kudoh, Hideaki [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan)

2006-05-15T23:59:59.000Z

34

Tensor modes on the string theory landscape  

E-Print Network [OSTI]

We attempt an estimate for the distribution of the tensor mode fraction $r$ over the landscape of vacua in string theory. The dynamics of eternal inflation and quantum tunneling lead to a kind of democracy on the landscape, providing no bias towards large-field or small-field inflation regardless of the class of measure. The tensor mode fraction then follows the number frequency distributions of inflationary mechanisms of string theory over the landscape. We show that an estimate of the relative number frequencies for small-field vs large-field inflation, while unattainable on the whole landscape, may be within reach as a regional answer for warped Calabi-Yau flux compactifications of type IIB string theory.

Alexander Westphal

2012-12-22T23:59:59.000Z

35

Perturbative String Thermodynamics near Black Hole Horizons  

E-Print Network [OSTI]

We provide further computations and ideas to the problem of near-Hagedorn string thermodynamics near (uncharged) black hole horizons, building upon our earlier work JHEP 1403 (2014) 086. The relevance of long strings to one-loop black hole thermodynamics is emphasized. We then provide an argument in favor of the absence of $\\alpha'$-corrections for the (quadratic) heterotic thermal scalar action in Rindler space. We also compute the large $k$ limit of the cigar orbifold partition functions (for both bosonic and type II superstrings) which allows a better comparison between the flat cones and the cigar cones. A discussion is made on the general McClain-Roth-O'Brien-Tan theorem and on the fact that different torus embeddings lead to different aspects of string thermodynamics. The black hole/string correspondence principle for the 2d black hole is discussed in terms of the thermal scalar. Finally, we present an argument to deal with arbitrary higher genus partition functions, suggesting the breakdown of string perturbation theory (in $g_s$) to compute thermodynamical quantities in black hole spacetimes.

Thomas G. Mertens; Henri Verschelde; Valentin I. Zakharov

2014-10-29T23:59:59.000Z

36

What is Decidable about Strings?  

E-Print Network [OSTI]

We prove several decidability and undecidability results for the satisfiability/validity problem of formulas over a language of finite-length strings and integers (interpreted as lengths of strings). The atomic formulas ...

Ganesh, Vijay

2011-02-01T23:59:59.000Z

37

Witten Index and Superconducting Strings  

E-Print Network [OSTI]

The Yukawa interaction sector of superstring inspired models that give superconducting strings, can be described in terms of a supersymmetric quantum mechanics algebra. We relate the Witten index of susy quantum mechanics with an index characteristic to superconducting string models.

V. K. Oikonomou

2010-01-14T23:59:59.000Z

38

Probing the String Landscape  

ScienceCinema (OSTI)

We are currently in the throes of a potentially huge paradigm shift in physics. Motivated by recent developments in string theory and the discovery of the so-called "string landscape", physicists are beginning to question the uniqueness of fundamental theories of physics and the methods by which such theories might be understood and investigated. In this colloquium, I will give a non-technical introduction to the nature of this paradigm shift and how it developed. I will also discuss some of the questions to which it has led, and the nature of the controversies it has spawned.

Keith Dienes

2010-01-08T23:59:59.000Z

39

The Langlands Program and String Modular K3 Surfaces  

E-Print Network [OSTI]

A number theoretic approach to string compactification is developed for Calabi-Yau hypersurfaces in arbitrary dimensions. The motivic strategy involved is illustrated by showing that the Hecke eigenforms derived from Galois group orbits of the holomorphic two-form of a particular type of K3 surfaces can be expressed in terms of modular forms constructed from the worldsheet theory. The process of deriving string physics from spacetime geometry can be reversed, allowing the construction of K3 surface geometry from the string characters of the partition function. A general argument for K3 modularity follows from mirror symmetry, in combination with the proof of the Shimura-Taniyama conjecture.

Rolf Schimmrigk

2006-03-29T23:59:59.000Z

40

AdS String: Classical Solutions and Moduli Dynamics  

E-Print Network [OSTI]

We review some recent work and techniques for constructing dynamical string solutions in AdS spacetime. These solutions generalize the folded string and multi-spike solutions of GKP and Kruczenski. The methods developed for constructing these dynamical solutions are based on Pohlmeyer reduction to integrable sinh-Gordon type equations. The integrability of the equations is seen as the crucial tool for reconstruction of the string configurations. We discuss the physical meaning of these dynamical spike solutions and the question of their moduli space.

Antal Jevicki; Kewang Jin

2010-01-29T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

New Retrievable Coil Anchors: Preliminary In Vivo Experiences in Swine  

SciTech Connect (OSTI)

Purpose. To design and test retrievable coil anchors to improve the safety and efficacy of coil embolization. Methods. Fifty-two 0.038-inch homemade retrievable stainless steel coils were equipped with one of four different pre-shaped nitinol anchors and tested in 38 pigs. All coils with the anchor were completely retrieved and redeployed 3-18 times (median 7 times) prior to release. Types 1 and 2 anchored coils were acutely deployed in the external iliac arteries (n = 10 each), and chronically tested (1 week) in the common carotid arteries (n = 6 each). Larger type 1 (n = 4), type 3 (n = 6), and type 4 (n = 4) anchored coils were acutely deployed in the abdominal aorta. The largest type 1 anchors (n = 6) were acutely tested in the inferior vena cava. Results. All anchored coils were successfully retrieved and repositioned several times. All but two coils formed a compact plug and there was no coil migration except with two mechanically defective type 3 anchors. Conclusion. The use of retrievable anchors allowed the coils to be retrieved and repositioned, prevented coil migration, and enabled compact coil configuration.

Konya, A., E-mail: akonya@mdanderson.org; Wright, K.C. [University of Texas M.D. Anderson Cancer Center, Section of Interventional Radiology, Division of Diagnostic Imaging (United States)

2005-04-15T23:59:59.000Z

42

Information Retrieval Leif Azzopardi  

E-Print Network [OSTI]

. ECIR'08: Proceedings of the IR research, 30th European conference on Advances in information retrieval: Proceedings of the 29th annual international ACM SIGIR conference on Research and development in information analogue to language. SIGIR '05: Proceedings of the 28th annual international ACM SIGIR conference

Azzopardi, Leif

43

Current balancing for battery strings  

DOE Patents [OSTI]

A battery plant is described which features magnetic circuit means for balancing the electrical current flow through a pluraliircuitbattery strings which are connected electrically in parallel. The magnetic circuit means is associated with the battery strings such that the conductors carrying the electrical current flow through each of the battery strings pass through the magnetic circuit means in directions which cause the electromagnetic fields of at least one predetermined pair of the conductors to oppose each other. In an alternative embodiment, a low voltage converter is associated with each of the battery strings for balancing the electrical current flow through the battery strings.

Galloway, James H. (New Baltimore, MI)

1985-01-01T23:59:59.000Z

44

Thermal Duality Transformations and the Canonical Ensemble: The Deconfining Long String Phase Transition  

E-Print Network [OSTI]

We give a first principles formulation of the equilibrium statistical mechanics of strings in the canonical ensemble, compatible with the Euclidean timelike T-duality transformations that link the six supersymmetric string theories in pairs. We demonstrate that each exhibits a T^2 growth in the free energy at high temperatures far above the string scale. We verify that the low energy field theory limit of our expression for the string free energy reproduces the expected T^{10} growth when the contribution from massive string modes is suppressed. In every case, heterotic, type I, and type II, we can definitively rule out the occurrence of an exponential divergence in the one-loop string free energy above some critical temperature. Finally, we identify a macroscopic loop amplitude in the type I string theories which yields the expectation value of a single Wilson-Polyakov-Susskind loop in the low energy finite temperature supersymmetric gauge theory limit, an order parameter for a thermal phase transition at a string scale temperature. We point out that precise computations can nevertheless be carried out on either side of the phase boundary by using the low energy finite temperature supersymmetric gauge theory limits of the pair of thermal dual string theories, type IB and type I'. Note Added (Sep 2005).

Shyamoli Chaudhuri

2005-09-06T23:59:59.000Z

45

Forecast constraints on cosmic string parameters from gravitational wave direct detection experiments  

E-Print Network [OSTI]

Gravitational waves (GWs) are one of the key signatures of cosmic strings. If GWs from cosmic strings are detected in future experiments, not only their existence can be confirmed but also their properties might be probed. In this paper, we study the determination of cosmic string parameters through direct detection of GW signatures in future ground-based GW experiments. We consider two types of GWs, bursts and the stochastic GW background, which provide us with different information about cosmic string properties. Performing the Fisher matrix calculation on the cosmic string parameters, such as parameters governing the string tension $G\\mu$ and initial loop size $\\alpha$ and the reconnection probability $p$, we find that the two different types of GW can break degeneracies in some of these parameters and provide better constraints than those from each measurement.

Sachiko Kuroyanagi; Koichi Miyamoto; Toyokazu Sekiguchi; Keitaro Takahashi; Joseph Silk

2012-06-25T23:59:59.000Z

46

Coulomb string tension, asymptotic string tension, and the gluon chain  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

We compute, via numerical simulations, the non-perturbative Coulomb potential and position-space ghost propagator in pure SU(3) gauge theory in Coulomb gauge. We find that that the Coulomb potential scales nicely in accordance with asymptotic freedom, that the Coulomb potential is linear in the infrared, and that the Coulomb string tension is about four times larger than the asymptotic string tension. We explain how it is possible that the asymptotic string tension can be lower than the Coulomb string tension by a factor of four.

Greensite, Jeff; Szczepaniak, Adam P.

2015-02-01T23:59:59.000Z

47

Physics of String Flux Compactifications  

E-Print Network [OSTI]

We provide a qualitative review of flux compactifications of string theory, focusing on broad physical implications and statistical methods of analysis.

Frederik Denef; Michael R. Douglas; Shamit Kachru

2007-01-06T23:59:59.000Z

48

Intelligent Information Retrieval  

E-Print Network [OSTI]

Since it was first announced at ADASS 2 the Smithsonian/NASA Astrophysics System Abstract Service (ADS) has played a central role in the information seeking behavior of astronomers. Central to the ability of the ADS to act as a search and discovery tool is its role as metadata agregator. Over the past 13 years the ADS has introduced many new techniques to facilitate information retrieval, broadly defined. We discuss some of these developments; with particular attention to how the ADS might interact with the virtual observatory, and to the new myADS-arXiv customized open access virtual journal. The ADS is at http://ads.harvard.edu

Michael J. Kurtz; Guenther Eichhorn; Alberto Accomazzi; Carolyn Grant; Edwin Henneken; Stephen S. Murray

2005-10-31T23:59:59.000Z

49

EM-21 Retrieval Knowledge Center: Waste Retrieval Challenges  

SciTech Connect (OSTI)

EM-21 is the Waste Processing Division of the Office of Engineering and Technology, within the U.S. Department of Energy’s (DOE) Office of Environmental Management (EM). In August of 2008, EM-21 began an initiative to develop a Retrieval Knowledge Center (RKC) to provide the DOE, high level waste retrieval operators, and technology developers with centralized and focused location to share knowledge and expertise that will be used to address retrieval challenges across the DOE complex. The RKC is also designed to facilitate information sharing across the DOE Waste Site Complex through workshops, and a searchable database of waste retrieval technology information. The database may be used to research effective technology approaches for specific retrieval tasks and to take advantage of the lessons learned from previous operations. It is also expected to be effective for remaining current with state-of-the-art of retrieval technologies and ongoing development within the DOE Complex. To encourage collaboration of DOE sites with waste retrieval issues, the RKC team is co-led by the Savannah River National Laboratory (SRNL) and the Pacific Northwest National Laboratory (PNNL). Two RKC workshops were held in the Fall of 2008. The purpose of these workshops was to define top level waste retrieval functional areas, exchange lessons learned, and develop a path forward to support a strategic business plan focused on technology needs for retrieval. The primary participants involved in these workshops included retrieval personnel and laboratory staff that are associated with Hanford and Savannah River Sites since the majority of remaining DOE waste tanks are located at these sites. This report summarizes and documents the results of the initial RKC workshops. Technology challenges identified from these workshops and presented here are expected to be a key component to defining future RKC-directed tasks designed to facilitate tank waste retrieval solutions.

Fellinger, Andrew P.; Rinker, Michael W.; Berglin, Eric J.; Minichan, Richard L.; Poirier, Micheal R.; Gauglitz, Phillip A.; Martin, Bruce A.; Hatchell, Brian K.; Saldivar, Eloy; Mullen, O Dennis; Chapman, Noel F.; Wells, Beric E.; Gibbons, Peter W.

2009-04-10T23:59:59.000Z

50

CMB distortions from damping of acoustic waves produced by cosmic strings  

SciTech Connect (OSTI)

We study diffusion damping of acoustic waves in the photon-baryon fluid due to cosmic strings, and calculate the induced ?- and y-type spectral distortions of the cosmic microwave background. For cosmic strings with tension within current bounds, their contribution to the spectral distortions is subdominant compared to the distortions from primordial density perturbations.

Tashiro, Hiroyuki; Sabancilar, Eray; Vachaspati, Tanmay, E-mail: Hiroyuki.Tashiro@asu.edu, E-mail: Eray.Sabancilar@asu.edu, E-mail: tvachasp@asu.edu [Physics Department, Arizona State University, Tempe, Arizona 85287 (United States)

2013-08-01T23:59:59.000Z

51

Subcritical String and Large N QCD  

E-Print Network [OSTI]

We pursue the possibility of using subcritical string theory in 4 space-time dimensions to establish a string dual for large N QCD. In particular we study the even G-parity sector of the 4 dimensional Neveu-Schwarz dual resonance model as the natural candidate for this string theory. Our point of view is that the open string dynamics given by this model will {\\it determine} the appropriate subcritical closed string theory, a tree level background of which should describe the sum of planar multi-loop open string diagrams. We examine the one loop open string diagram, which contains information about the closed string spectrum at weak coupling. Higher loop open string diagrams will be needed to determine closed string interactions. We also analyze the field theory limit of the one loop open string diagram and recover the correct running coupling behavior of the limiting gauge theory.

Charles B. Thorn

2010-06-29T23:59:59.000Z

52

Subcritical string and large N QCD  

SciTech Connect (OSTI)

We pursue the possibility of using subcritical string theory in 4 spacetime dimensions to establish a string dual for large N QCD. In particular we study the even G-parity sector of the 4 dimensional Neveu-Schwarz dual resonance model as the natural candidate for this string theory. Our point of view is that the open string dynamics given by this model will determine the appropriate subcritical closed string theory, a tree level background of which should describe the sum of planar multiloop open string diagrams. We examine the one-loop open string diagram, which contains information about the closed string spectrum at weak coupling. Higher loop open string diagrams will be needed to determine closed string interactions. We also analyze the field theory limit of the one-loop open string diagram and recover the correct running coupling behavior of the limiting gauge theory.

Thorn, Charles B. [Institute for Fundamental Theory, Department of Physics, University of Florida, Gainesville Florida 32611 (United States)

2008-10-15T23:59:59.000Z

53

Summing Planar Bosonic Open Strings  

SciTech Connect (OSTI)

In earlier work, planar graphs of massless {phi}{sup 3} theory were summed with the help of the light cone world sheet picture and the mean field approximation. In the present article, the same methods are applied to the problem of summing planar bosonic open strings. They find that in the ground state of the system, string boundaries form a condensate on the world sheet, and a new string emerges from this summation. Its slope is always greater than the initial slope, and it remains non-zero even when the initial slope is set equal to zero. If they assume the initial string tends to a field a theory in the zero slope limit, this result provides evidence for string formation in field theory.

Bardakci, Korkut

2006-02-16T23:59:59.000Z

54

Dynamical String Tension in String Theory with Spacetime Weyl Invariance  

E-Print Network [OSTI]

The fundamental string length, which is an essential part of string theory, explicitly breaks scale invariance. However, in field theory we demonstrated recently that the gravitational constant, which is directly related to the string length, can be promoted to a dynamical field if the standard model coupled to gravity (SM+GR) is lifted to a locally scale (Weyl) invariant theory. The higher gauge symmetry reveals previously unknown field patches whose inclusion turn the classically conformally invariant SM+GR into a geodesically complete theory with new cosmological and possibly further physical consequences. In this paper this concept is extended to string theory by showing how it can be Weyl lifted with a local scale symmetry acting on target space background fields. In this process the string tension (fundamental string length) is promoted to a dynamical field, in agreement with the parallel developments in field theory. We then propose a string theory in a geodesically complete cosmological stringy background which suggests previously unimagined directions in the stringy exploration of the very early universe.

Itzhak Bars; Paul Steinhardt; Neil Turok

2014-07-15T23:59:59.000Z

55

Topological insulators and superconductors from string theory  

SciTech Connect (OSTI)

Topological insulators and superconductors in different spatial dimensions and with different discrete symmetries have been fully classified recently, revealing a periodic structure for the pattern of possible types of topological insulators and superconductors, both in terms of spatial dimensions and in terms of symmetry classes. It was proposed that K theory is behind the periodicity. On the other hand, D-branes, a solitonic object in string theory, are also known to be classified by K theory. In this paper, by inspecting low-energy effective field theories realized by two parallel D-branes, we establish a one-to-one correspondence between the K-theory classification of topological insulators/superconductors and D-brane charges. In addition, the string theory realization of topological insulators and superconductors comes naturally with gauge interactions, and the Wess-Zumino term of the D-branes gives rise to a gauge field theory of topological nature, such as ones with the Chern-Simons term or the {theta} term in various dimensions. This sheds light on topological insulators and superconductors beyond noninteracting systems, and the underlying topological field theory description thereof. In particular, our string theory realization includes the honeycomb lattice Kitaev model in two spatial dimensions, and its higher-dimensional extensions. Increasing the number of D-branes naturally leads to a realization of topological insulators and superconductors in terms of holography (AdS/CFT).

Ryu, Shinsei; Takayanagi, Tadashi [Department of Physics, University of California, Berkeley, California 94720 (United States); Institute for the Physics and Mathematics of the Universe (IPMU), University of Tokyo, Kashiwa, Chiba 277-8582 (Japan)

2010-10-15T23:59:59.000Z

56

Topological Insulators and Superconductors from String Theory  

E-Print Network [OSTI]

Topological insulators and superconductors in different spatial dimensions and with different discrete symmetries have been fully classified recently, revealing a periodic structure for the pattern of possible types of topological insulators and supercondutors, both in terms of spatial dimensions and in terms of symmetry classes. It was proposed that K-theory is behind the periodicity. On the other hand, D-branes, a solitonic object in string theory, are also known to be classified by K-theory. In this paper, by inspecting low-energy effective field theories realized by two parallel D-branes, we establish a one-to-one correspondence between the K-theory classification of topological insulators/superconductors and D-brane charges. In addition, the string theory realization of topological insulators and superconductors comes naturally with gauge interactions, and the Wess-Zumino term of the D-branes gives rise to a gauge field theory of topological nature, such as ones with the Chern-Simons term or the $\\theta$-term in various dimensions. This sheds light on topological insulators and superconductors beyond non-interacting systems, and the underlying topological field theory description thereof. In particular, our string theory realization includes the honeycomb lattice Kitaev model in two spatial dimensions, and its higher-dimensional extensions. Increasing the number of D-branes naturally leads to a realization of topological insulators and superconductors in terms of holography (AdS/CFT).

Shinsei Ryu; Tadashi Takayanagi

2010-08-01T23:59:59.000Z

57

Toward understanding of differences in current cloud retrievals of ARM ground-based measurements  

SciTech Connect (OSTI)

Accurate observations of cloud microphysical properties are needed for evaluating and improving the representation of cloud processes in climate models and better estimate of the Earth radiative budget. However, large differences are found in current cloud products retrieved from ground-based remote sensing measurements using various retrieval algorithms. Understanding the differences is an important step to address uncertainties in the cloud retrievals. In this study, an in-depth analysis of nine existing ground-based cloud retrievals using ARM remote sensing measurements is carried out. We place emphasis on boundary layer overcast clouds and high level ice clouds, which are the focus of many current retrieval development efforts due to their radiative importance and relatively simple structure. Large systematic discrepancies in cloud microphysical properties are found in these two types of clouds among the nine cloud retrieval products, particularly for the cloud liquid and ice particle effective radius. Note that the differences among some retrieval products are even larger than the prescribed uncertainties reported by the retrieval algorithm developers. It is shown that most of these large differences have their roots in the retrieval theoretical bases, assumptions, as well as input and constraint parameters. This study suggests the need to further validate current retrieval theories and assumptions and even the development of new retrieval algorithms with more observations under different cloud regimes.

Zhao C.; Dunn M.; Xie, S.; Klein, S. A.; Protat, A.; Shupe, M. D.; McFarlane, S. A.; Comstock, J. M.; Delanoë, J.; Deng, M.; Hogan, R. J.; Huang, D.; Jensen, M. P.; Mace, G. G.; McCoy, R.; O’Connor, E. J.; Turner, D. D.; Wang, Z.

2012-05-30T23:59:59.000Z

58

CRAD, Criticality Safety - Idaho Accelerated Retrieval Project...  

Broader source: Energy.gov (indexed) [DOE]

Criticality Safety - Idaho Accelerated Retrieval Project Phase II CRAD, Criticality Safety - Idaho Accelerated Retrieval Project Phase II February 2006 A section of Appendix C to...

59

CRAD, Occupational Safety & Health - Idaho Accelerated Retrieval...  

Broader source: Energy.gov (indexed) [DOE]

Occupational Safety & Health - Idaho Accelerated Retrieval Project Phase II CRAD, Occupational Safety & Health - Idaho Accelerated Retrieval Project Phase II February 2006 A...

60

Holography and the Canonical Ensemble of Fermionic Strings  

E-Print Network [OSTI]

We show that the canonical ensemble in any of the six supersymmetric string theories, type IIA and IIB, type IB and type I', or heterotic E_8 x E_8 and Spin(32)/Z_2, exhibits a strong version of holography: the growth of the number of degrees of freedom in the free energy at high temperatures is identical to that in a two-dimensional quantum field theory. We clarify the precise nature of the thermal duality phase transition in each case, confirming that it lies within the Kosterlitz-Thouless universality class. We show that, in the presence of Dbranes, and a consequent Yang-Mills gauge sector, the thermal ensemble of type II strings is infrared stable, with neither tachyons nor massless scalar tadpoles. Supersymmetry remains unbroken in the oriented closed string sector, but is broken by thermal effects in the full unoriented open and closed type I string theory. We identify an order parameter for an unusual phase transition in the worldvolume gauge theory signalled by the short distance behavior of the pair correlator of timelike Wilson loops. Note Added (Sep 2005).

Shyamoli Chaudhuri

2005-09-12T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Geometry, topology, and string theory  

SciTech Connect (OSTI)

A variety of scenarios are considered which shed light upon the uses and limitations of classical geometric and topological notions in string theory. The primary focus is on situations in which D-brane or string probes of a given classical space-time see the geometry quite differently than one might naively expect. In particular, situations in which extra dimensions, non-commutative geometries as well as other non-local structures emerge are explored in detail. Further, a preliminary exploration of such issues in Lorentzian space-times with non-trivial causal structures within string theory is initiated.

Varadarajan, Uday

2003-07-10T23:59:59.000Z

62

CHALLENGES WITH RETRIEVING TRANSURANIC WASTE FROM THE HANFORD BURIAL GROUNDS  

SciTech Connect (OSTI)

The U.S. DOE's Hanford Reservation produced plutonium and other nuclear materials for the nation's defense starting in World War II. The defense mission generated wastes that were either retrievably stored (i.e. retrievably stored waste) and/or disposed of in burial grounds. Challenges have emerged from retrieving suspect TRU waste including adequacy of records, radiological concerns, container integrity, industrial hygiene and safety issues, the lack of processing/treatment facilities, and the integration of regulatory requirements. All retrievably stored waste is managed as mixed waste and assumed to be TRU waste, unless documented otherwise. Mixed waste is defined as radioactive waste that contains hazardous constituents. The Atomic Energy Act governs waste with radionuclides, and the Resource Conservation and Recovery Act (RCRA) governs waste with hazardous constituents. Waste may also be governed by the Toxic Substances Control Act (TSCA), and a portion may be managed under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). In 1970, TRU waste was required to be placed in 20-year retrievable storage and segregated from other Waste. Prior to that date, segregation did not occur. Because of the changing definition of TRU over the years, and the limitations of early assay equipment, all retrievably stored waste in the burial grounds is managed as suspect TRU. Experience has shown that some of this waste will be characterized as low-level (non-TRU) waste after assay. The majority of the retrieved waste is not amenable to sampling due to waste type and/or radiological issues. Key to waste retrieval and disposition are characterization, historical investigation and research, knowledge of past handling and packaging, as well as a broad understanding and application of the regulations.

SWAN, R.J.; LAKES, M.E.

2007-08-06T23:59:59.000Z

63

Quantum Corrections in String Compactifications on SU(3) Structure Geometries  

E-Print Network [OSTI]

We investigate quantum corrections to the classical four-dimensional low-energy effective action of type II string theory compactified on SU(3) structure geometries. Various methods previously developed for Calabi-Yau compactifications are adopted to determine - under some simple assumptions about the low-energy degrees of freedom - the leading perturbative corrections to the moduli space metrics in both alpha' and the string coupling constant. We find - in complete analogy to the Calabi-Yau case - that the corrections take a universal form dependent only on the Euler characteristic of the six-dimensional compact space.

Mariana Grana; Jan Louis; Ulrich Theis; Daniel Waldram

2014-12-05T23:59:59.000Z

64

Toward Understanding of Differences in Current Cloud Retrievals of ARM Ground-based Measurements  

SciTech Connect (OSTI)

Accurate observations of cloud microphysical properties are needed for evaluating and improving the representation of cloud processes in climate models. However, large differences are found in current cloud products retrieved from ground-based remote sensing measurements using various retrieval algorithms. Understanding the differences is an important step to address uncertainties in the cloud retrievals. In this study, an in-depth analysis of nine existing ground-based cloud retrievals using ARM remote sensing measurements is carried out. We place emphasize on boundary layer overcast clouds and high level ice clouds, which are the focus of many current retrieval development efforts due to their radiative importance and relatively simple structure. Large systematic discrepancies in cloud microphysical properties are found in these two types of clouds among the nine cloud retrieval products, particularly for the cloud liquid and ice effective radius. It is shown that most of these large differences have their roots in the retrieval algorithms used by these cloud products, including the retrieval theoretical bases, assumptions, as well as input and constraint parameters. This study suggests the need to further validate current retrieval theories and assumptions and even the development of new retrieval algorithms with more observations under different cloud regimes.

Zhao, Chuanfeng; Xie, Shaocheng; Klein, Stephen A.; Protat, Alain; Shupe, Matthew D.; McFarlane, Sally A.; Comstock, Jennifer M.; Delanoe, Julien; Deng, Min; Dunn, Maureen; Hogan, Robin; Huang, Dong; Jensen, Michael; Mace, Gerald G.; McCoy, Renata; O'Conner, Ewan J.; Turner, Dave; Wang, Zhien

2012-05-30T23:59:59.000Z

65

Toroidal Orbifolds: Resolutions, Orientifolds and Applications in String Phenomenology  

E-Print Network [OSTI]

This thesis is concerned with the geometry of toroidal orbifolds and their applications in string theory. By resolving the orbifold singularities via blow-ups, one arrives at a smooth Calabi-Yau manifold. The systematic method to do so is explained in detail. Also the transition to the Orientifold quotient is explained. In the second part of this thesis, applications in string phenomenology are discussed. The applications belong to the framework of compactifications with fluxes in type IIB string theory. The first example belongs to the category of model building, flux-induced soft supersymmetry breaking parameters are worked out explicitly. The second example belongs to the subject of moduli stabilization along the lines of the KKLT proposal. Orientifold models which result from resolutions of toroidal orbifolds are discussed as possible candidate models for an explicit realization of the KKLT proposal.

S. Reffert

2006-09-05T23:59:59.000Z

66

Acoustic data transmission through a drill string  

DOE Patents [OSTI]

Acoustical signals are transmitted through a drill string by canceling upward moving acoustical noise and by preconditioning the data in recognition of the comb filter impedance characteristics of the drill string. 5 figs.

Drumheller, D.S.

1988-04-21T23:59:59.000Z

67

Quadratic superconducting cosmic strings revisited  

E-Print Network [OSTI]

It has been shown that 5-dimensional general relativity action extended by appropriate quadratic terms admits a singular superconducting cosmic string solution. We search for cosmic strings endowed with similar and extended physical properties by directly integrating the non-linear matrix field equations thus avoiding the perturbative approach by which we constructed the above-mentioned \\textsl{exact} solution. The most general superconducting cosmic string, subject to some constraints, will be derived and shown to be mathematically \\textsl{unique} up to linear coordinate transformations mixing its Killing vectors. The most general solution, however, is not globally equivalent to the old one due to the existence of Killing vectors with closed orbits.

Mustapha Azreg-Aďnou

2008-02-22T23:59:59.000Z

68

Twenty-five questions for string theorists  

SciTech Connect (OSTI)

In an effort to promote communication between the formal and phenomenological branches of the high-energy theory community, we provide a description of some important issues in supersymmetric and string phenomenology. We describe each within the context of string constructions, illustrating them with specific examples where applicable. Each topic culminates in a set of questions that we believe are amenable to direct consideration by string theorists, and whose answers we think could help connect string theory and phenomenology.

Binetruy, Pierre; /Orsay, LPT; Kane, G.L.; /Michigan U., MCTP; Lykken, Joseph D.; /Fermilab; Nelson, Brent D.; /Pennsylvania U.

2005-09-01T23:59:59.000Z

69

p-Adic Strings and Their Applications  

SciTech Connect (OSTI)

The theory of p-adic strings is reviewed along with some of their applications, foremost among them to the tachyon condensation problem in string theory. Some open problems are discussed, in particular that of the superstring in 10 dimensions as the end-stage of the 26-dimensional closed bosonic string's tachyon condensation.

Freund, Peter G. O. [Enrico Fermi Institute, University of Chicago, Chicago, IL 60637 (United States); Department of Physics, University of Chicago, Chicago, IL 60637 (United States)

2006-03-29T23:59:59.000Z

70

Sustainability of multi-field inflation and bound on string scale  

E-Print Network [OSTI]

We study the effects of the interaction terms between the inflaton fields on the inflationary dynamics in multi-field models. With power law type potential and interactions, the total number of e-folds may get considerably reduced and can lead to unacceptably short period of inflation. Also we point out that this can place a bound on the characteristic scale of the underlying theory such as string theory. Using a simple multi-field chaotic inflation model from string theory, the string scale is constrained to be larger than the scale of grand unified theory.

Jinn-Ouk Gong

2009-02-11T23:59:59.000Z

71

CRAD, Engineering - Idaho Accelerated Retrieval Project Phase...  

Broader source: Energy.gov (indexed) [DOE]

Engineering - Idaho Accelerated Retrieval Project Phase II CRAD, Engineering - Idaho Accelerated Retrieval Project Phase II February 2006 A section of Appendix C to DOE G 226.1-2...

72

CRAD, Management - Idaho Accelerated Retrieval Project Phase...  

Broader source: Energy.gov (indexed) [DOE]

Management - Idaho Accelerated Retrieval Project Phase II CRAD, Management - Idaho Accelerated Retrieval Project Phase II February 2006 A section of Appendix C to DOE G 226.1-2...

73

CRAD, Radiological Controls - Idaho Accelerated Retrieval Project...  

Broader source: Energy.gov (indexed) [DOE]

Accelerated Retrieval Project Phase II CRAD, Radiological Controls - Idaho Accelerated Retrieval Project Phase II February 2006 A section of Appendix C to DOE G 226.1-2 "Federal...

74

CRAD, Emergency Management - Idaho Accelerated Retrieval Project...  

Broader source: Energy.gov (indexed) [DOE]

Idaho Accelerated Retrieval Project Phase II CRAD, Emergency Management - Idaho Accelerated Retrieval Project Phase II February 2006 A section of Appendix C to DOE G 226.1-2...

75

Repudiative Information Retrieval Dmitri Asonov  

E-Print Network [OSTI]

, that a record retrieved is or is not the j-th record for any 1 j N. The first problem is called PIR, and we call the second problem the RIR problem. State of the art PIR protocols with optimal query response- ening PIR to RIR. In particular, we propose a RIR protocol with optimal query response time

Freytag, Johann-Christoph

76

Project Name Project Number Tagging Type  

E-Print Network [OSTI]

Project Name Project Number Primary Tagging Type Secondary Tagging Type Fish Species Tagging/ Secondary Legal Driver (BiOp, MOA, Accord, etc.) Tagging Purpose Funded Entity Tagging Location Retrieval CWT Recovery Project 2010-036-00 CWT PIT Chinook, coho retrieval, analysis, address PSMFC sampling

77

Ultraviolet Limit of Open String Theory  

E-Print Network [OSTI]

We confirm the intuition that a string theory which is perturbatively infrared finite is automatically perturbatively ultraviolet finite. Our derivation based on the asymptotics of the Selberg trace formula for the Greens function on a Riemann surface holds for both open and closed string amplitudes and is independent of modular invariance and supersymmetry. The mass scale for the open strings stretched between Dbranes suggests a natural world-sheet ultraviolet regulator in the string path integral, preserving both T-duality and open-closed string world-sheet duality. Note added (Jan 2005): Comments and related references added.

Shyamoli Chaudhuri

2005-01-21T23:59:59.000Z

78

Superconducting Hair on Charged Black String Background  

E-Print Network [OSTI]

Behaviour of Dirac fermions in the background of a charged black string penetrated by an Abelian Higgs vortex is elaborated. One finds the evidence that the system under consideration can support fermion fields acting like a superconducting cosmic string in the sence that a nontrivial Dirac fermion field can be carried by the system in question. The case of nonextremal and extremal black string vortex systems were considered. The influence of electric and Higgs charge, the winding number and the fermion mass on the fermion localization near the black string event horizon was studied. It turned out that the extreme charged black string expelled fermion fields more violently comparing to the nonextremal one.

Lukasz Nakonieczny; Marek Rogatko

2012-01-25T23:59:59.000Z

79

String universality in ten dimensions  

E-Print Network [OSTI]

We show that the ${\\cal N}=1$ supergravity theories in ten dimensions with gauge groups $U(1)^{496}$ and $E_8 \\times U(1)^{248}$ are not consistent quantum theories. Cancellation of anomalies cannot be made compatible with supersymmetry and abelian gauge invariance. Thus, in ten dimensions all supersymmetric theories of gravity without known inconsistencies are realized in string theory.

Allan Adams; Oliver DeWolfe; Washington Taylor

2014-10-29T23:59:59.000Z

80

Web Information Retrieval Web Science Course  

E-Print Network [OSTI]

1 Web Information Retrieval Web Science Course #12;2 #12;What to Expect · Information Retrieval on the Web ­ Differences to traditional IR · Selected Papers 3 #12;4 Information Retrieval Basics #12 documents on the Internet ­ Searching the World Wide Web #12;16 Recent IR History · 2000's ­ Link analysis

Nejdl, Wolfgang

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Forecast constraints on cosmic strings from future CMB, pulsar timing and gravitational wave direct detection experiments  

E-Print Network [OSTI]

We study future observational constraints on cosmic string parameters from various types of next-generation experiments: direct detection of gravitational waves (GWs), pulsar timing array, and the cosmic microwave background (CMB). We consider both GW burst and stochastic GW background searches by ground- and space-based interferometers as well as GW background detection in pulsar timing experiments. We also consider cosmic string contributions to the CMB temperature and polarization anisotropies. These different types of observations offer independent probes of cosmic strings and may enable us to investigate cosmic string properties if the signature is detected. In this paper, we evaluate the power of future experiments to constrain cosmic string parameters, such as the string tension Gmu, the initial loop size alpha, and the reconnection probability p, by performing Fisher information matrix calculations. We find that combining the information from the different types of observations breaks parameter degeneracies and provides more stringent constraints on the parameters. We also find future space-borne interferometers independently provide a highly precise determination of the parameters.

Sachiko Kuroyanagi; Koichi Miyamoto; Toyokazu Sekiguchi; Keitaro Takahashi; Joseph Silk

2013-02-19T23:59:59.000Z

82

Transuranic (TRU) Waste Phase I Retrieval Plan  

SciTech Connect (OSTI)

Phase I retrieval of post-1970 TRU wastes from burial ground 218-W-4C can be done in a safe, efficient, and cost-effective manner. Initiating TRU retrieval by retrieving uncovered drums from Trenches 1, 20, and 29, will allow retrieval to begin under the current SWBG safety authorization basis. The retrieval of buried drums from Trenches 1, 4, 20, and 29, which will require excavation, will commence once the uncovered drum are retrieved. This phased approach allows safety analysis for drum venting and drum module excavation to be completed and approved before the excavation proceeds. In addition, the lessons learned and the operational experience gained from the retrieval of uncovered drums can be applied to the more complicated retrieval of the buried drums. Precedents that have been set at SRS and LANL to perform retrieval without a trench cover, in the open air, should be followed. Open-air retrieval will result in significant cost savings over the original plans for Phase I retrieval (Project W-113). Based on LANL and SRS experience, open-air retrieval will have no adverse impacts to the environment or to the health and safety of workers or the public. Assaying the waste in the SWBG using a mobile assay system, will result in additional cost savings. It is expected that up to 50% of the suspect-TRU wastes will assay as LLW, allowing those waste to remain disposed of in the SWBG. Further processing, with its associated costs, will only occur to the portion of the waste that is verified to be TRU. Retrieval should be done, to the extent possible, under the current SWBG safety authorization basis as a normal part of SWBG operations. The use of existing personnel and existing procedures should be optimized. By working retrieval campaigns, typically during the slow months, it is easier to coordinate the availability of necessary operations personnel, and it is easier to coordinate the availability of a mobile assay vendor.

MCDONALD, K.M.

1999-08-27T23:59:59.000Z

83

Filter for a drill string  

DOE Patents [OSTI]

A filter for a drill string comprises a perforated receptacle having an open end and a perforated end and first and second mounting surfaces are adjacent the open end. A transmission element is disposed within each of the first and second mounting surfaces. A capacitor may modify electrical characteristics of an LC circuit that comprises the transmission elements. The respective transmission elements are in communication with each other and with a transmission network integrated into the drill string. The transmission elements may be inductive couplers, direct electrical contacts, or optical couplers. In some embodiments of the present invention, the filter comprises an electronic component. The electronic component may be selected from the group consisting of a sensor, a router, a power source, a clock source, a repeater, and an amplifier.

Hall, David R. (Provo, UT); Pixton, David S. (Lehi, UT); Briscoe, Michael (Lehi, UT); McPherson, James (Sandy, UT)

2007-12-04T23:59:59.000Z

84

Loop Gas Model for Open Strings  

E-Print Network [OSTI]

The open string with one-dimensional target space is formulated in terms of an SOS, or loop gas, model on a random surface. We solve an integral equation for the loop amplitude with Dirichlet and Neumann boundary conditions imposed on different pieces of its boundary. The result is used to calculate the mean values of order and disorder operators, to construct the string propagator and find its spectrum of excitations. The latter is not sensible neither to the string tension $\\L$ nor to the mass $\\mu$ of the ``quarks'' at the ends of the string. As in the case of closed strings, the SOS formulation allows to construct a Feynman diagram technique for the string interaction amplitudes.

V. Kazakov; I. Kostov

1992-05-18T23:59:59.000Z

85

Initial ACTR retrieval technology evaluation test material recommendations  

SciTech Connect (OSTI)

Millions of gallons of radiaoctive waste are contained in underground storage tanks at Hanford (SE Washington). Techniques for retrieving much of this waste from the storage tanks have been developed. Current baseline approach is to use sluice jets for single-shell tanks and mixer pumps for double-shell tanks. The Acquire Commercial Technology for Retrieval (ACTR) effort was initiated to identify potential improvements in or alternatives to the baseline waste retrieval methods. Communications with a variety of vendors are underway to identify improved methods that can be implemented at Hanford with little or no additional development. Commercially available retrieval methods will be evaluated by a combination of testing and system-level cost estimation. Current progress toward developing waste simulants for testing ACTR candidate methods is reported; the simulants are designed to model 4 different types of tank waste. Simulant recipes are given for wet sludge, hardpan/dried sludge,hard saltcake, and soft saltcake. Comparisons of the waste and simulant properties are documented in this report.

Powell, M.R.

1996-04-01T23:59:59.000Z

86

Innovative grout/retrieval demonstration final report  

SciTech Connect (OSTI)

This report presents the results of an evaluation of an innovative retrieval technique for buried transuranic waste. Application of this retrieval technique was originally designed for full pit retrieval; however, it applies equally to a hot spot retrieval technology. The technique involves grouting the buried soil waste matrix with a jet grouting procedure, applying an expansive demolition grout to the matrix, and retrieving the debris. The grouted matrix provides an agglomeration of fine soil particles and contaminants resulting in an inherent contamination control during the dusty retrieval process. A full-scale field demonstration of this retrieval technique was performed on a simulated waste pit at the Idaho National Engineering Laboratory. Details are reported on all phases of this proof-of-concept demonstration including pit construction, jet grouting activities, application of the demolition grout, and actual retrieval of the grouted pit. A quantitative evaluation of aerosolized soils and rare earth tracer spread is given for all phases of the demonstration, and these results are compared to a baseline retrieval activity using conventional retrieval means. 8 refs., 47 figs., 10 tabs.

Loomis, G.G.; Thompson, D.N.

1995-01-01T23:59:59.000Z

87

Gamma Ray Bursts from Ordinary Cosmic Strings  

E-Print Network [OSTI]

We give an upper estimate for the number of gamma ray bursts from ordinary (non-superconducting) cosmic strings expected to be observed at terrestrial detectors. Assuming that cusp annihilation is the mechanism responsible for the bursts we consider strings arising at a GUT phase transition and compare our estimate with the recent BATSE results. Further we give a lower limit for the effective area of future detectors designed to detect the cosmic string induced flux of gamma ray bursts.

R. H. Brandenberger; A. T. Sornborger; M. Trodden

1993-02-12T23:59:59.000Z

88

Gravitational Phase Operator and Cosmic Strings  

E-Print Network [OSTI]

A quantum equivalence principle is formulated by means of a gravitational phase operator which is an element of the Poincare group. This is applied to the spinning cosmic string which suggests that it may (but not necessarily) contain gravitational torsion. A new exact solution of the Einstein- Cartan-Sciama-Kibble equations for the gravitational field with torsion is obtained everywhere for a cosmic string with uniform energy density, spin density and flux. A novel effect due to the quantized gravitational field of the cosmic string on the wave function of a particle outside the string is used to argue that spacetime points are not meaningful in quantum gravity.

J. Anandan

1995-12-14T23:59:59.000Z

89

Brane World Models Need Low String Scale  

E-Print Network [OSTI]

Models with large extra dimensions offer the possibility of the Planck scale being of order the electroweak scale, thus alleviating the gauge hierarchy problem. We show that these models suffer from a breakdown of unitarity at around three quarters of the low effective Planck scale. An obvious candidate to fix the unitarity problem is string theory. We therefore argue that it is necessary for the string scale to appear below the effective Planck scale and that the first signature of such models would be string resonances. We further translate experimental bounds on the string scale into bounds on the effective Planck scale.

Antoniadis, Ignatios; Calmet, Xavier

2011-01-01T23:59:59.000Z

90

Recent Progress in Weakly-Coupled Heterotic String Phenomenology  

E-Print Network [OSTI]

Coupled Heterotic String Phenomenology Yi-Yen Wu TheoreticalHeterotic String Phenomenology ? arXiv:hep-ph/9707498v1 28coupled heterotic string phenomenology are reviewed. We

Wu, Yi-Yen

2009-01-01T23:59:59.000Z

91

ARM Cloud Retrieval Ensemble Data Set (ACRED)  

SciTech Connect (OSTI)

This document describes a new Atmospheric Radiation Measurement (ARM) data set, the ARM Cloud Retrieval Ensemble Data Set (ACRED), which is created by assembling nine existing ground-based cloud retrievals of ARM measurements from different cloud retrieval algorithms. The current version of ACRED includes an hourly average of nine ground-based retrievals with vertical resolution of 45 m for 512 layers. The techniques used for the nine cloud retrievals are briefly described in this document. This document also outlines the ACRED data availability, variables, and the nine retrieval products. Technical details about the generation of ACRED, such as the methods used for time average and vertical re-grid, are also provided.

Zhao, C; Xie, S; Klein, SA; McCoy, R; Comstock, JM; Delanoë, J; Deng, M; Dunn, M; Hogan, RJ; Jensen, MP; Mace, GG; McFarlane, SA; O’Connor, EJ; Protat, A; Shupe, MD; Turner, D; Wang, Z

2011-09-12T23:59:59.000Z

92

MA et al.: SKETCH RETRIEVAL VIA STROKE FEATURES 1 Sketch Retrieval via Dense Stroke Features  

E-Print Network [OSTI]

MA et al.: SKETCH RETRIEVAL VIA STROKE FEATURES 1 Sketch Retrieval via Dense Stroke Features Chao search method. In this paper, we propose a representation scheme which takes sketch strokes into account with local features, thereby facilitat- ing efficient retrieval with codebooks. Stroke features are detected

Yang, Ming-Hsuan

93

Your FAFSA and the IRS Data Retrieval Tool What is the IRS Data Retrieval Tool?  

E-Print Network [OSTI]

Your FAFSA and the IRS Data Retrieval Tool What is the IRS Data Retrieval Tool? The U.S. Department of Education and the Internal Revenue Service (IRS) have collaborated to develop a tool that simplifies the completion of the FAFSA application. The IRS Data Retrieval tool allows FAFSA applicants and parents

Moore, Paul A.

94

TeV Scale Strings and Scattering Amplitudes at the LHC  

E-Print Network [OSTI]

We study aspects of TeV string scale models of intersecting D-branes. The gauge bosons arise from strings ending on stacks of D-branes, whereas chiral matter arises from strings stretched between intersecting D-branes. Our focus is on scattering amplitudes (at tree-level), Regge states (string excitations), and collider phenomenology. Achieving a low string scale is possible in models of Large extra dimensions. At the LHC, a low enough string scale implies that cross sections will deviate from their standard model predictions. Moreover, Regge states as well as Kaluza-Klein states and winding states may be produced. In a large class of intersecting D-brane models, the quark-gluon amplitudes with at most 2 quarks turn out to be independent of the geometry of the extra dimensions. Therefore these type of amplitudes, which we call "universal amplitudes", are model independent. The universal amplitudes involve exchanges of Regge states only, whereas amplitudes with more then 2 quarks also involve exchanges of KK and winding states. The main computational part is concerned with suggesting methods to calculate the decay widths of the Regge states, and with the formalism for treating amplitudes containing exchanges of higher spin particles. Also included is a large review part.

Dean Carmi

2014-11-07T23:59:59.000Z

95

Energy Production in the Formation of a Finite Thickness Cosmic String  

E-Print Network [OSTI]

The classical electromagnetic modes outside a long, straight, superconducting cosmic string are calculated, assuming the string to be surrounded by a superconducting cylindric surface of radius R. Thereafter, by use of a Bogoliubov-type argument, the electromagnetic energy W produced per unit length in the lowest two modes is calculated when the string is formed "suddenly". The essential new element in the present analysis as compared with prior work of Parker [Phys. Rev. Lett. {\\bf 59}, 1369 (1987)] and Brevik and Toverud [Phys. Rev. D {\\bf 51}, 691 (1995)], is that the radius {\\it a} of the string is assumed finite, thus necessitating Neumann functions to be included in the fundamental modes. We find that the theory is changed significantly: W is now strongly concentrated in the lowest mode $(m,s)=(0,1)$, whereas the proportionality $W \\propto (G\\mu /t)^2$ that is characteristic for zero-width strings is found in the next mode (1,1). Here G is the gravitational constant, $\\mu$ the string mass per unit length, and t the GUT time.

I. Brevik; A. G. Frřseth

1999-09-29T23:59:59.000Z

96

Derandomizing from Random Strings Harry Buhrman  

E-Print Network [OSTI]

Derandomizing from Random Strings Harry Buhrman CWI and University of Amsterdam buhrman c log n, R=c log n K , itself a strings of length nc , is complex enough to figure as a hard an alternative proof of the existence of an r.e. set A, due to Barzdin [4], such that for all time bounds t

Fortnow, Lance

97

Are multiple parton interactions important at high energies? New types of hadrons production processes  

E-Print Network [OSTI]

Hadrons interaction at high energies is carried out by one color gluon exchange. All quarks and gluons contained in colliding hadrons take part in interaction and production of particles. The contribution of multiple parton interactions is negligible. Multiple hadrons production at high energies occurs only in three types of processes. The first process is hadrons production in gluon string, the second is hadrons production in two quark strings and the third is hadrons production in three quark strings. In proton-proton interaction production of only gluon string and two quark strings is possible. In proton-antiproton interaction production of gluon string, two quark strings and three quark strings is possible. Therefore multiplicity distributions in proton-proton and proton-antiproton interactions are different.

V. A. Abramovsky

2009-11-25T23:59:59.000Z

98

Wiggly cosmic strings accrete dark energy  

E-Print Network [OSTI]

This paper deals with a study of the cylindrically symmetric accretion of dark energy with equation of state $p=w\\rho$ onto wiggly straight cosmic strings. We have obtained that when $w>-1$ the linear energy density in the string core gradually increases tending to a finite maximum value as time increases for all considered dark energy models. On the regime where the dominant energy condition is violated all such models predict a steady decreasing of the linear energy density of the cosmic strings as phantom energy is being accreted. The final state of the string after such an accretion process is a wiggleless defect. It is argued however that if accreation of phantom energy would proceed by successive quantum steps then the defect would continue losing linear energy density until a minimum nonzero value which can be quite smaller than that corresponding to the unperturbed string.

Pedro F. Gonzalez-Diaz; Jose A. Jimenez Madrid

2005-06-29T23:59:59.000Z

99

String Gas Cosmology and Non-Gaussianities  

E-Print Network [OSTI]

Recently it has been shown that string gas cosmology, an alternative model of the very early universe which does not involve a period of cosmological inflation, can give rise to an almost scale invariant spectrum of metric perturbations. Here we calculate the non-Gaussianities of the spectrum of cosmological fluctuations in string gas cosmology, and find that these non-Gaussianities depend linearly on the wave number and that their amplitude depends sensitively on the string scale. If the string scale is at the TeV scale, string gas cosmology could lead to observable non-Gaussianities, if it is close to the Planck scale, then the non-Gaussianities on current cosmological scales are negligible.

Bin Chen; Yi Wang; Wei Xue; Robert Brandenberger

2008-03-05T23:59:59.000Z

100

Bose-Einstein condensate strings  

E-Print Network [OSTI]

We consider the possible existence of gravitationally bound general relativistic strings consisting of Bose-Einstein condensate (BEC) matter which is described, in the Newtonian limit, by the zero temperature time-dependent nonlinear Schr\\"odinger equation (the Gross-Pitaevskii equation), with repulsive interparticle interactions. In the Madelung representation of the wave function, the quantum dynamics of the condensate can be formulated in terms of the classical continuity equation and the hydrodynamic Euler equations. In the case of a condensate with quartic nonlinearity, the condensates can be described as a gas with two pressure terms, the interaction pressure, which is proportional to the square of the matter density, and the quantum pressure, which is without any classical analogue though, when the number of particles in the system is high enough, the latter may be neglected. By assuming cylindrical symmetry, we analyze the physical properties of the BEC strings in both the interaction pressure and quantum pressure dominated limits, by numerically integrating the gravitational field equations. In this way we obtain a large class of stable stringlike astrophysical objects, whose basic parameters (mass density and radius) depend sensitively on the mass and scattering length of the condensate particle, as well as on the quantum pressure of the Bose-Einstein gas.

Tiberiu Harko; Matthew J. Lake

2015-01-17T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Geodesic Shape Retrieval via Optimal Mass Transport  

E-Print Network [OSTI]

Geodesic Shape Retrieval via Optimal Mass Transport Julien Rabin, Gabriel Peyr´e, and Laurent D presents a new method for 2-D and 3-D shape retrieval based on geodesic signatures. These signatures of geodesic distance maps to each point. The resulting high dimensional distributions are matched to perform

Boyer, Edmond

102

Computationally Private Information Retrieval with Polylogarithmic Communication  

E-Print Network [OSTI]

information retrieval. The notion of private information retrieval (PIR for short) was introduced by Chor, Goldreich, Kushilevitz and Sudan [CGKS95] and has already received a lot of attention. The study of PIR for mobile users.) Ideally, the PIR problem consists of devising a communication protocol involving just two

Cachin, Christian

103

Optimal Estimation Retrieval Aerosol Microphysical Properties  

E-Print Network [OSTI]

SAGE II Satellite Observations A thesis submitted in partial fulfillment of the requirements or entirely insensitive. A successful retrieval algorithm must then be able (a) to fill the `blind spot functions. The three main parts of this thesis are (1) the development of the new OE retrieval algorithm, (2

Oxford, University of

104

QFT, String Temperature and the String Phase of de Sitter Space-time  

E-Print Network [OSTI]

The density of mass levels \\rho(m) and the critical temperature for strings in de Sitter space-time are found. QFT and string theory in de Sitter space are compared. A `Dual'-transform is introduced which relates classical to quantum string lengths, and more generally, QFT and string domains. Interestingly, the string temperature in De Sitter space turns out to be the Dual transform of the QFT-Hawking-Gibbons temperature. The back reaction problem for strings in de Sitter space is addressed selfconsistently in the framework of the `string analogue' model (or thermodynamical approach), which is well suited to combine QFT and string study.We find de Sitter space-time is a self-consistent solution of the semiclassical Einstein equations in this framework. Two branches for the scalar curvature R(\\pm) show up: a classical, low curvature solution (-), and a quantum high curvature solution (+), enterely sustained by the strings. There is a maximal value for the curvature R_{\\max} due to the string back reaction. Int...

Medrano, M R

1999-01-01T23:59:59.000Z

105

Records Management Procedures for Storage, Transfer and Retrieval...  

Broader source: Energy.gov (indexed) [DOE]

Procedures for Storage, Transfer and Retrieval of Records from WNRC Records Management Procedures for Storage, Transfer and Retrieval of Records from WNRC Develop and maintain a...

106

Biomedical Information Retrieval based on Document-Level Term Boosting.  

E-Print Network [OSTI]

?? There are several problems regarding information retrieval on biomedical information. The common methods for information retrieval tend to fall short when searching in this… (more)

Johannsson, Dagur Valberg

2009-01-01T23:59:59.000Z

107

Cerenkov radiation from moving straight strings  

E-Print Network [OSTI]

We study Cerenkov radiation from moving straight strings which glisse with respect to each other in such a way that the projected intersection point moves faster than light. To calculate this effect we develop classical perturbation theory for the system of Nambu-Goto strings interacting with dilaton, two-form and gravity. In the first order one encounters divergent self-action terms which are eliminated by classical renormalization of the string tension. Cerenkov radiation arises in the second order. It is generated by an effective source which contains contributions localized on the strings world-sheets and bulk contributions quadratic in the first order fields. In the ultra-relativistic limit radiation exhibits angular peaking on the Cerenkov cone in the forward direction of the fast string in the rest frame of another. The radiation spectrum then extends up to high frequencies proportional to square of the Lorentz-factor of the relative velocity. Gravitational radiation is absent since the 1+2 space-time transverse to the straight string does not allow for gravitons. A rough estimate of the Cerenkov radiation in the cosmological cosmic strings network is presented.

D. V. Gal'tsov; E. Yu. Melkumova; K. Salehi

2006-12-30T23:59:59.000Z

108

Effects of overlapping strings in pp collisions  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

In models for hadron collisions based on string hadronization, the strings are usually treated as independent, allowing no interaction between the confined colour fields. In studies of nucleus collisions it has been suggested that strings close in space can fuse to form "colour ropes." Such ropes are expected to give more strange particles and baryons, which also has been suggested as a signal for plasma formation. Overlapping strings can also be expected in pp collisions, where usually no phase transition is expected. In particular at the high LHC energies the expected density of strings is quite high. To investigate possible effects of rope formation, we present a model in which strings are allowed to combine into higher multiplets, giving rise to increased production of baryons and strangeness, or recombine into singlet structures and vanish. Also a crude model for strings recombining into junction structures is considered, again giving rise to increased baryon production. The models are implemented in the DIPSY MC event generator, using PYTHIA8 for hadronization, and comparison to pp minimum bias data, reveals improvement in the description of identified particle spectra.

Bierlich, Christian [Lund University; Gustafson, Gösta [Lund University; Lönnblad, Leif [Lund University; Tarasov, Andrey [JLAB

2015-03-01T23:59:59.000Z

109

Apparatus in a drill string  

DOE Patents [OSTI]

An apparatus in a drill string comprises an internally upset drill pipe. The drill pipe comprises a first end, a second end, and an elongate tube intermediate the first and second ends. The elongate tube and the ends comprising a continuous an inside surface with a plurality of diameters. A conformable spirally welded metal tube is disposed within the drill pipe intermediate the ends thereof and terminating adjacent to the ends of the drill pipe. The conformable metal tube substantially conforms to the continuous inside surface of the metal tube. The metal tube may comprise a non-uniform section which is expanded to conform to the inside surface of the drill pipe. The non-uniform section may comprise protrusions selected from the group consisting of convolutions, corrugations, flutes, and dimples. The non-uniform section extends generally longitudinally along the length of the tube.

Hall, David R. (Provo, UT); Dahlgren, Scott (Alpine, UT); Hall, Jr., Tracy H. (Provo, UT); Fox, Joe (Lehi, UT); Pixton, David S. (Provo, UT)

2007-07-17T23:59:59.000Z

110

Topological Solitons in Helical Strings  

E-Print Network [OSTI]

The low-energy physics of (quasi)degenerate one-dimensional systems is typically understood as the particle-like dynamics of kinks between stable, ordered structures. Such dynamics, we show, becomes highly non-trivial when the ground states are topologically constrained: a dynamics of the domains rather than on the domains which the kinks separate. Motivated by recently reported observations of charged polymers physisorbed on nanotubes, we study kinks between helical structures of a string wrapping around a cylinder. While their motion cannot be disentangled from domain dynamics, and energy and momentum is not concentrated in the solitons, the dynamics of the domains can be folded back into a one-particle picture.

Cristiano Nisoli; Alexander V. Balatsky

2014-11-26T23:59:59.000Z

111

String Landscape and Supernovae Ia  

E-Print Network [OSTI]

We present a model for the triggering of Supernovae Ia (SN Ia) by a phase transition to exact supersymmetry (susy) in the core of a white dwarf star. The model, which accomodates the data on SN Ia and avoids the problems of the standard astrophysical accretion based picture, is based on string landscape ideas and assumes that the decay of the false broken susy vacuum is enhanced at high density. In a slowly expanding susy bubble, the conversion of pairs of fermions to pairs of degenerate scalars releases a significant amount of energy which induces fusion in the surrounding normal matter shell. After cooling, the absence of degeneracy pressure causes the susy bubble to collapse to a black hole of about 0.1 solar mass or to some other stable susy object.

L. Clavelli

2011-10-09T23:59:59.000Z

112

A Proposal for Altering the Unification Scale in String Theory  

E-Print Network [OSTI]

An ensemble of short open strings in equilibrium with the heat bath provided by the Euclidean worldvolume of a stack of Dbranes undergoes a thermal phase transition to a long string phase. The transition temperature is just below the string scale. We point out that this phenomenon provides a simple mechanism within open and closed string theories for altering the strong-electro-weak coupling unification scale relative to the fundamental closed string mass scale in spacetimes with external electromagnetic background.

Shyamoli Chaudhuri

2005-02-18T23:59:59.000Z

113

Solid waste retrieval. Phase 1, Operational basis  

SciTech Connect (OSTI)

This Document describes the operational requirements, procedures, and options for execution of the retrieval of the waste containers placed in buried storage in Burial Ground 218W-4C, Trench 04 as TRU waste or suspect TRU waste under the activity levels defining this waste in effect at the time of placement. Trench 04 in Burial Ground 218W-4C is totally dedicated to storage of retrievable TRU waste containers or retrievable suspect TRU waste containers and has not been used for any other purpose.

Johnson, D.M.

1994-09-30T23:59:59.000Z

114

Fuel Retrieval System Design Verification Report  

SciTech Connect (OSTI)

The Fuel Retrieval Subproject was established as part of the Spent Nuclear Fuel Project (SNF Project) to retrieve and repackage the SNF located in the K Basins. The Fuel Retrieval System (FRS) construction work is complete in the KW Basin, and start-up testing is underway. Design modifications and construction planning are also underway for the KE Basin. An independent review of the design verification process as applied to the K Basin projects was initiated in support of preparation for the SNF Project operational readiness review (ORR). A Design Verification Status Questionnaire, Table 1, is included which addresses Corrective Action SNF-EG-MA-EG-20000060, Item No.9 (Miller 2000).

GROTH, B.D.

2000-04-11T23:59:59.000Z

115

Exact sum rules for inhomogeneous strings  

SciTech Connect (OSTI)

We derive explicit expressions for the sum rules of the eigenvalues of inhomogeneous strings with arbitrary density and with different boundary conditions. We show that the sum rule of order N may be obtained in terms of a diagrammatic expansion, with (N?1)!/2 independent diagrams. These sum rules are used to derive upper and lower bounds to the energy of the fundamental mode of an inhomogeneous string; we also show that it is possible to improve these approximations taking into account the asymptotic behavior of the spectrum and applying the Shanks transformation to the sequence of approximations obtained to the different orders. We discuss three applications of these results. -- Highlights: •We derive an explicit expression for the sum rules of an inhomogeneous string. •We obtain a diagrammatic representation for the sum rules of a given order. •We obtain precise bounds on the lowest eigenvalue of the string.

Amore, Paolo, E-mail: paolo.amore@gmail.com

2013-11-15T23:59:59.000Z

116

Strings in plane-fronted gravitational waves  

E-Print Network [OSTI]

Brinkmann's plane-fronted gravitational waves with parallel rays --~shortly pp-waves~-- are shown to provide, under suitable conditions, exact string vacua at all orders of the sigma-model perturbation expansion.

C. Duval; Z. Horvath; P. A. Horvathy

2006-02-13T23:59:59.000Z

117

String Phenomenology in the Era of LHC  

E-Print Network [OSTI]

The low-energy supersymmetry phenomenology for specific classes of string compactifications is investigated given that the low-energy physics may provide a clue as to the structure of the fundamental theory at high energy scales. The one...

Maxin, James A.

2010-10-12T23:59:59.000Z

118

Aspects of grand unified and string phenomenology  

E-Print Network [OSTI]

Explored in this report is the essential interconnectedness of Grand Unified and String Theoretic Phenomenology. In order to extract a modeled connection to low-energy physics from the context of superstring theory, it is presently necessary...

Walker, Joel Wesley

2005-11-01T23:59:59.000Z

119

Fractal Strings and Multifractal Zeta Functions  

E-Print Network [OSTI]

decompositions of Moran fractals. Adv. Math. 92, 196–236 (Probab. 12, 8. Falconer, K. : Fractal Geometry—MathematicalB.M. , Lapidus, M.L. : Random fractal strings: their zeta

Lapidus, Michel L.; Lévy-Véhel, Jacques; Rock, John A.

2009-01-01T23:59:59.000Z

120

HTI retrieval demonstration project execution plan  

SciTech Connect (OSTI)

This plan describes the process for demonstrating the retrieval of difficult Hanford tank waste forms utilizing commercial technologies and the private sector to conduct the operations. The demonstration is to be conducted in Tank 241-C-106.

Ellingson, D.R.

1997-09-04T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Broad Expertise Retrieval in Sparse Data Environments  

E-Print Network [OSTI]

Balog,K. Bogers,T. Azzopardi,L. de Rijke,M. van den Bosch,A. To appear in the Proceedings of the 30th Annual ACM Conference on Research and Development in Information Retrieval (SIGIR 2007)

Balog, K.; Bogers, T.; Azzopardi, L.

122

Technical requirements specification for tank waste retrieval  

SciTech Connect (OSTI)

This document provides the technical requirements specification for the retrieval of waste from the underground storage tanks at the Hanford Site. All activities covered by this scope are conducted in support of the Tank Waste Remediation System (TWRS) mission.

Lamberd, D.L.

1996-09-26T23:59:59.000Z

123

IRS Data Retrieval Tool 2012-2013 FAFSA  

E-Print Network [OSTI]

1 IRS Data Retrieval Tool 2012-2013 FAFSA Financial Aid Office University of California, San Diego #12;2 What is the IRS Data Retrieval Tool? · The IRS Retrieval Tool gives FAFSA applicants and parents the ability to transfer their data from the IRS to the FAFSA · The Retrieval Tool saves time and increases

Russell, Lynn

124

Successful Approaches in the TREC Video Retrieval Evaluations  

E-Print Network [OSTI]

Terms Experimentation. Keywords Video retrieval, search, TRECVID, information retrieval benchmarks. 1 over the last three years. The task involves the search and retrieval of shots from MPEG digitized retrieval technologies. The search evaluations are grouped into interactive (with a human in the loop

Christel, Mike

125

Private Information Retrieval, Optimal for Users and Secure Coprocessors  

E-Print Network [OSTI]

@dbis.informatik.hu­berlin.de Abstract. A private information retrieval (PIR) protocol allows a user to retrieve one of N records from a database while hiding the identity of the record from the database server. A PIR protocol is optimal Private Information Retrieval (PIR) protocols. Formally, a PIR protocol allows a user to retrieve one of N

Freytag, Johann-Christoph

126

A Model for Serendipitous Music Retrieval Markus Schedl, David Hauger  

E-Print Network [OSTI]

Research Institute for Artificial Intellgence dominik.schnitzer@ofai.at ABSTRACT Music retrieval systems

Widmer, Gerhard

127

Phenomenology of heterotic and type II orientifold string models  

E-Print Network [OSTI]

on a variety of orientifold backgrounds. In particular, we construct ?ipped SU(5), Pati-Salam, and MSSM-like models. The phenomenological properties of these models are studied. For one model in particular, we ?nd that we may explain the quark masses...

Mayes, Van Eric

2009-05-15T23:59:59.000Z

128

Isometry Group Orbit Quantization of Spinning Strings in AdS_3 x S^3  

E-Print Network [OSTI]

Describing the bosonic AdS_3 x S^3 particle and string in SU(1,1) x SU(2) group variables, we provide a Hamiltonian treatment of the isometry group orbits of solutions via analysis of the pre-symplectic form. For the particle we obtain a one-parameter family of orbits parameterized by creation-annihilation variables, which leads to the Holstein-Primakoff realization of the isometry group generators. The scheme is then applied to spinning string solutions characterized by one winding number in AdS_3 and two winding numbers in S^3. We find a two-parameter family of orbits, where quantization again provides the Holstein-Primakoff realization of the symmetry generators with an oscillator type energy spectrum. Analyzing the minimal energy at strong coupling we verify the spectrum of short strings at special values of winding numbers.

Martin Heinze; George Jorjadze; Luka Megrelidze

2014-10-13T23:59:59.000Z

129

Strings at Finite Temperature: Wilson Lines, Free Energies, and the Thermal Landscape  

E-Print Network [OSTI]

According to the standard prescriptions, zero-temperature string theories can be extended to finite temperature by compactifying their time directions on a so-called "thermal circle" and implementing certain orbifold twists. However, the existence of a topologically non-trivial thermal circle leaves open the possibility that a gauge flux can pierce this circle --- i.e., that a non-trivial Wilson line (or equivalently a non-zero chemical potential) might be involved in the finite-temperature extension. In this paper, we concentrate on the zero-temperature heterotic and Type I strings in ten dimensions, and survey the possible Wilson lines which might be introduced in their finite-temperature extensions. We find a rich structure of possible thermal string theories, some of which even have non-traditional Hagedorn temperatures, and we demonstrate that these new thermal string theories can be interpreted as extrema of a continuous thermal free-energy "landscape". Our analysis also uncovers a unique finite-temperature extension of the heterotic SO(32) and $E_8\\times E_8$ strings which involves a non-trivial Wilson line, but which --- like the traditional finite-temperature extension without Wilson lines --- is metastable in this thermal landscape.

Keith R. Dienes; Michael Lennek; Menika Sharma

2012-05-25T23:59:59.000Z

130

BookProcessing public Book(string tit, string au, double pr, bool av)  

E-Print Network [OSTI]

Methods BookDB ProcessAllAvail BookProcessing Delegate b private List list; public BookDB() { list } public void ProcessAllAvail(BookProcessing Action) { foreach (Book b in list) { if (b.avail) { Action Author { get { return author;} } private string author; public class Book { private string title; private

Krupski, Vladimir Nickolayevich

131

String-Net Models with $Z_N$ Fusion Algebra  

E-Print Network [OSTI]

We study the Levin-Wen string-net model with a $Z_N$ type fusion algebra. Solutions of the local constraints of this model correspond to $Z_N$ gauge theory and double Chern-simons theories with quantum groups. For the first time, we explicitly construct a spin-$(N-1)/2$ model with $Z_N$ gauge symmetry on a triangular lattice as an exact dual model of the string-net model with a $Z_N$ type fusion algebra on a honeycomb lattice. This exact duality exists only when the spins are coupled to a $Z_N$ gauge field living on the links of the triangular lattice. The ungauged $Z_N$ lattice spin models are a class of quantum systems that bear symmetry-protected topological phases that may be classified by the third cohomology group $H^3(Z_N,U(1))$ of $Z_N$. Our results apply also to any case where the fusion algebra is identified with a finite group algebra or a quantusm group algebra.

Ling-Yan Hung; Yidun Wan

2012-12-19T23:59:59.000Z

132

Transuranic (TRU) Waste Phase I Retrieval Plan  

SciTech Connect (OSTI)

From 1970 to 1987, TRU and suspect TRU wastes at Hanford were placed in the SWBG. At the time of placement in the SWBG these wastes were not regulated under existing Resource Conservation and Recovery Act (RCRA) regulations, since they were generated and disposed of prior to the effective date of RCRA at the Hanford Site (1987). From the standpoint of DOE Order 5820.2A1, the TRU wastes are considered retrievably stored, and current plans are to retrieve these wastes for shipment to WIPP for disposal. This plan provides a strategy for the Phase I retrieval that meets the intent of TPA milestone M-91 and Project W-113, and incorporates the lessons learned during TRU retrieval campaigns at Hanford, LANL, and SRS. As in the original Project W-113 plans, the current plan calls for examination of approximately 10,000 suspect-TRU drums located in the 218-W-4C burial ground followed by the retrieval of those drums verified to contain TRU waste. Unlike the older plan, however, this plan proposes an open-air retrieval scenario similar to those used for TRU drum retrieval at LANL and SRS. Phase I retrieval consists of the activities associated with the assessment of approximately 10,000 55-gallon drums of suspect TRU-waste in burial ground 218-W-4C and the retrieval of those drums verified to contain TRU waste. Four of the trenches in 218-W-4C (Trenches 1, 4, 20, and 29) are prime candidates for Phase I retrieval because they contain large numbers of suspect TRU drums, stacked from 2 to 5 drums high, on an asphalt pad. In fact, three of the trenches (Trenches 1 , 20, and 29) contain waste that has not been covered with soil, and about 1500 drums can be retrieved without excavation. The other three trenches in 218-W-4C (Trenches 7, 19, and 24) are not candidates for Phase I retrieval because they contain significant numbers of boxes. Drums will be retrieved from the four candidate trenches, checked for structural integrity, overpacked, if necessary, and assayed at the burial ground. A mobile assay system will be used to determine if the drum is LLW (Le., contains <100 nCi/g). LLW will remain disposed of in the 218-W-4C Burial Ground. TRU waste will be retrieved and staged in the burial ground until it can be shipped to the CWC. The TRU drums will be stored at the CWC until they can be moved to WRAP. The WRAP facility will prepare the waste for shipment to WIPP for final disposal. For planning purposes, approximately 50% of the 10,000 drums have been estimated to contain LLW.

MCDONALD, K.M.

2000-09-28T23:59:59.000Z

133

Methods for Heel Retrieval for Tanks C-101, C-102, and C-111 at the Hanford Site - 13064  

SciTech Connect (OSTI)

The purpose of this paper is to evaluate the prospects of using bulk waste characteristics to determine the most appropriate heel retrieval technology. If the properties of hard to remove heels can be determined before bulk retrieval, then a heel retrieval technology can be selected before bulk retrieval is complete. This would save substantially on sampling costs and would allow the deployment of the heel retrieval technology immediately after bulk retrieval. The latter would also accelerate the heel removal schedule. A number of C-farm retrievals have been fully or partially completed at the time of this writing. Thus, there is already substantial information on the success of different technologies and the composition of the heels. There is also substantial information on the waste types in each tank based on historical records. Therefore, this study will correlate the performance of technologies used so far and compare them to the known waste types in the tanks. This will be used to estimate the performance of future C Farm heel retrievals. An initial decision tree is developed and employed on tanks C-101, C-102, and C 111. An assumption of this study is that no additional characterization information would be available, before or after retrieval. Note that collecting additional information would substantially increase the probability of success. Deploying some in-situ testing technologies, such as a water lance or an in-situ Raman probe, might substantially increase the probability of successfully selecting the process conditions without having to take samples from the tanks for laboratory analysis. (authors)

Sams, T.L.; Kirch, N.W.; Reynolds, J.H. [Washington River protection Solutions, Richland, WA 99352 (United States)] [Washington River protection Solutions, Richland, WA 99352 (United States)

2013-07-01T23:59:59.000Z

134

Methods for heel retrieval for tanks C-101, C-102, and C-111 at the Hanford Site  

SciTech Connect (OSTI)

The purpose of this paper is to evaluate the prospects of using bulk waste characteristics to determine the most appropriate heel retrieval technology. If the properties of hard to remove heels can be determined before bulk retrieval, then a heel retrieval technology can be selected before bulk retrieval is complete. This would save substantially on sampling costs and would allow the deployment of the heel retrieval technology immediately after bulk retrieval. The latter would also accelerate the heel removal schedule. A number of C-farm retrievals have been fully or partially completed at the time of this writing. Thus, there is already substantial information on the success of different technologies and the composition of the heels. There is also substantial information on the waste types in each tank based on historical records. Therefore, this study will correlate the performance of technologies used so far and compare them to the known waste types in the tanks. This will be used to estimate the performance of future C Farm heel retrievals. An initial decision tree is developed and employed on tanks C-101, C-102, and C 111. An assumption of this study is that no additional characterization information would be available, before or after retrieval. Note that collecting additional information would substantially increase the probability of success. Deploying some in-situ testing technologies, such as a water lance or an in-situ Raman probe, might substantially increase the probability of successfully selecting the process conditions without having to take samples from the tanks for laboratory analysis.

Sams, Terry L. [Washington River Protection Solutions, LLC, Richland, WA (United States); Kirch, N. W. [Washington River Protection Solutions, LLC, Richland, WA (United States); Reynolds, Jacob G. [Washington River Protection Solutions, LLC, Richland, WA (United States)

2013-01-11T23:59:59.000Z

135

Have You Used LED Light Strings? | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

read about LED holiday light strings, which can use 90% less energy than regular incandescent light strings. You may even be able to save on the initial costs with rebates from...

136

A worldsheet perspective on string inflation  

E-Print Network [OSTI]

We investigate the constraints of slow-roll inflation on the string worldsheet. A general gravity-matter set-up is used in which the worldsheet consists of an abstract CFT coupled to a 3+1 dimensional non-linear sigma model. The empirical slow-roll parameters are expressed in terms of the beta functions of operators in the matter/internal CFT and the beta function of the dilaton. The result confirms that inflation is only sensitive to macroscopic properties of the matter sector, and that in string theory inflation is a non-perturbative (in g_s) phenomenon and one must go beyond tree-level string theory.

Koenraad Schalm; Ted van der Aalst

2010-08-30T23:59:59.000Z

137

Relativistic elasticity of rigid rods and strings  

E-Print Network [OSTI]

We show that the equation of motion for a rigid one-dimensional elastic body (i.e. a rod or string whose speed of sound is equal to the speed of light) in a two-dimensional spacetime is simply the wave equation. We then solve this equation in a few simple examples: a rigid rod colliding with an unmovable wall, a rigid rod being pushed by a constant force, a rigid string whose endpoints are simultaneously set in motion (seen as a special case of Bell's spaceships paradox), and a radial rigid string that has partially crossed the event horizon of a Schwarzschild black hole while still being held from the outside.

Jose Natario

2014-09-30T23:59:59.000Z

138

Fractal Strings and Multifractal Zeta Functions  

E-Print Network [OSTI]

For a Borel measure on the unit interval and a sequence of scales that tend to zero, we define a one-parameter family of zeta functions called multifractal zeta functions. These functions are a first attempt to associate a zeta function to certain multifractal measures. However, we primarily show that they associate a new zeta function, the topological zeta function, to a fractal string in order to take into account the topology of its fractal boundary. This expands upon the geometric information garnered by the traditional geometric zeta function of a fractal string in the theory of complex dimensions. In particular, one can distinguish between a fractal string whose boundary is the classical Cantor set, and one whose boundary has a single limit point but has the same sequence of lengths as the complement of the Cantor set. Later work will address related, but somewhat different, approaches to multifractals themselves, via zeta functions, partly motivated by the present paper.

Michel L. Lapidus; Jacques Levy Vehel; John A. Rock

2009-02-09T23:59:59.000Z

139

Confinement and the Short Type I' Flux Tube  

E-Print Network [OSTI]

We show that the recent world-sheet analysis of the quantum fluctuations of a short flux tube in type II string theory leads to a simple and precise description of a pair of stuck D0branes in an orientifold compactification of the type I' string theory. The existence of a stable type I' flux tube of sub-string-scale length is a consequence of the confinement of quantized flux associated with the scalar dualized ten-form background field strength *F_{10}, evidence for a -2brane in the BPS spectrum of M theory. Using heterotic-type I duality, we infer the existence of an M2brane of finite width O(\\sqrt{\\alpha'}) in M-theory, the strong coupling resolution of a spacetime singularity in the D=9 twisted and toroidally compactified E_8 x E_8 heterotic string. This phenomenon has a bosonic string analog in the existence of a stable short electric flux tube arising from the confinement of photons due to tachyon field dynamics. The appendix clarifies the appearance of nonperturbative states and enhanced gauge symmetry in toroidal compactifications of the type I' string. We account for all of the known disconnected components of the moduli space of theories with sixteen supercharges, in striking confirmation of heterotic-type I duality.

Shyamoli Chaudhuri

2000-07-18T23:59:59.000Z

140

Non-Abelian String-Net Ladders  

E-Print Network [OSTI]

We study the string-net model with a string tension for non-Abelian particles in the ladder geometry. Focusing on the simplest non-Abelian theory with a total quantum dimension larger than two, we find evidence for a "russian doll" spectrum featuring size-independent energy levels. Contrary to Fibonacci and Ising ladders, the spectrum is found to be gapped at the self-dual points and low-energy excitations in the ground-state sector consist in two-quasiparticle bound states that are discussed in the weak-tension limit. We argue that such properties are prototypical of theories containing more than one non-Abelian particle.

M. D. Schulz; S. Dusuel; J. Vidal

2014-10-15T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Electron string ion sources for carbon ion cancer therapy accelerators  

E-Print Network [OSTI]

The Electron String type of Ion Sources (ESIS) was developed, constructed and tested first in the Joint Institute for Nuclear Research. These ion sources can be the appropriate sources for production of pulsed C4+ and C6+ ion beams which can be used for cancer therapy accelerators. In fact the test ESIS Krion-6T already now at the solenoid magnetic field only 4.6 T provides more than 10^10 C4+ ions per pulse and about 5*10^9 C6+ ions per pulse. Such ion sources could be suitable for application at synchrotrons. It was also found, that Krion-6T can provide more than 10^11 C6+ ions per second at 100 Hz repetition rate, and the repetition rate can be increased at the same or larger ion output per second. This makes ESIS applicable at cyclotrons as well. As for production of 11C radioactive ion beams ESIS can be the most economic kind of ion source. To proof that the special cryogenic cell for pulse injection of gaseous species into electron string was successfully tested using the ESIS Krion-2M.

Boytsov, A Yu; Donets, E D; Donets, E E; Katagiri, K; Noda, K; Ponkin, D O; Ramzdorf, A Yu; Salnikov, V V; Shutov, V B

2015-01-01T23:59:59.000Z

142

String Theory clues for the low-$\\ell$ CMB ?  

E-Print Network [OSTI]

"Brane Supersymmetry Breaking" is a peculiar string-scale mechanism that can unpair Bose and Fermi excitations in orientifold models. It results from the simultaneous presence, in the vacuum, of collections of D-branes and orientifolds that are not mutually BPS, and is closely tied to the scale of string excitations. It also leaves behind, for a mixing of dilaton and internal breathing mode, an exponential potential that is just too steep for a scalar to emerge from the initial singularity while descending it. As a result, in this class of models the scalar can generically bounce off the exponential wall, and this dynamics brings along, in the power spectrum, an infrared depression typically followed by a pre-inflationary peak. We elaborate on a possible link between this type of bounce and the low-$\\ell$ end of the CMB angular power spectrum. For the first 32 multipoles, one can reach a 50 % reduction in $\\chi^{\\,2}$ with respect to the standard $\\Lambda$CDM setting.

Kitazawa, N

2014-01-01T23:59:59.000Z

143

Subword-based approaches for spoken document retrieval  

E-Print Network [OSTI]

This thesis explores approaches to the problem of spoken document retrieval (SDR), which is the task of automatically indexing and then retrieving relevant items from a large collection of recorded speech messages in ...

Ng, Kenney, 1967-

2000-01-01T23:59:59.000Z

144

CRAD, Safety Basis - Idaho Accelerated Retrieval Project Phase...  

Broader source: Energy.gov (indexed) [DOE]

Idaho Accelerated Retrieval Project Phase II CRAD, Safety Basis - Idaho Accelerated Retrieval Project Phase II February 2006 A section of Appendix C to DOE G 226.1-2 "Federal Line...

145

Somme esempio PhysicalAddr = firstlast:String, addr:String  

E-Print Network [OSTI]

:String, email:String Addr = PhysicalAddr + VirtualAddr inl : "PhysicalAddr- > PhysicalAddr + VirtualAddr" inr : "VirtualAddr- > PhysicalAddr + VirtualAddr" getName = a:Addr. case a of inl x ==> x.firstlast | inr y ==> y.name; Semantica, Mariangiola Dezani, a.a. 2003-2004 1 #12;' & $ % Nuove forme sintattiche t ::= ... terms inl

Dezani-Ciancaglini, Mariangiola

146

Somme esempio PhysicalAddr = {firstlast:String, addr:String}  

E-Print Network [OSTI]

:String, email:String} Addr = PhysicalAddr + VirtualAddr inl : "PhysicalAddr- > PhysicalAddr + VirtualAddr" inr : "VirtualAddr- > PhysicalAddr + VirtualAddr" getName = a:Addr. case a of inl x ==> x.firstlast | inr y ==> y.name; Semantica, Mariangiola Dezani, a.a. 2004-2005 1 #12;' & $ % Nuove forme sintattiche t ::= ... termini inl

Dezani-Ciancaglini, Mariangiola

147

Iterative Algorithms for Ptychographic Phase Retrieval  

SciTech Connect (OSTI)

Ptychography promises diffraction limited resolution without the need for high resolution lenses. To achieve high resolution one has to solve the phase problem for many partially overlapping frames. Here we review some of the existing methods for solving ptychographic phase retrieval problem from a numerical analysis point of view, and propose alternative methods based on numerical optimization.

Yang, Chao; Qian, Jianliang; Schirotzek, Andre; Maia, Filipe; Marchesini, Stefano

2011-05-03T23:59:59.000Z

148

RETRIEVAL OF OTTOMAN DOCUMENTS Bilkent University  

E-Print Network [OSTI]

RETRIEVAL OF OTTOMAN DOCUMENTS Esra ATAER Bilkent University Department of Computer Engineering Ottoman docu- ments stored in large archives and therefore managing tools for automatic searching, indexing and transcription of these documents is required. In this paper, we present a method

Duygulu-Sahin, Pinar

149

Synchronous Collaborative Information Retrieval with Relevance Feedback  

E-Print Network [OSTI]

. A user enters a search query and the search engine Retrieval. returns a list of documents according interacting with a search engine and performing knowledge amongst co-searchers. In our system this transfer a search task, is still an individual activity. We propose an of knowledge is achieved through

Lee, Hyowon

150

Outsourced Private Information Retrieval Yizhou Huang  

E-Print Network [OSTI]

. Information-theoretic PIR (IT-PIR) schemes are"perfectly secure" in the same sense as above--even a server is computational PIR (CPIR), whose security relies on certain cryp a scheme for outsourcing Private Information Retrieval (PIR) to untrusted servers while protecting

Goldberg, Ian

151

Private Information Retrieval Using Trusted Hardware  

E-Print Network [OSTI]

for Infocomm Research, Singapore baofeng@i2r.a-star.edu.sg Abstract. Many theoretical PIR (Private Information Retrieval) con- structions have been proposed in the past years. Though information theoretically secure complexity. The re- cent trend in outsourcing databases fuels the research on practical PIR schemes

Ding, Xuhua

152

Computationally Private Information Retrieval with Polylogarithmic Communication  

E-Print Network [OSTI]

. The notion of private information retrieval (PIR for short) was introduced by Chor, Goldreich, Kushilevitz and Sudan [CGKS95] and has already received a lot of attention. The study of PIR is motivated by the growing, the PIR problem consists of devising a communication protocol involving just two parties, the database

Cachin, Christian

153

Computationally Private Information Retrieval With Polylogarithmic Communication  

E-Print Network [OSTI]

. The beautiful notion of private information retrieval (PIR for short) was introduced by Chor, Goldreich, Kushilevitz and Sudan [CGKS95] and has already received a lot of attention. The study of PIR is motivated.) Ideally, the PIR problem consists of devising a communication protocol involving just two parties

Goldwasser, Shafi

154

Web Information Retrieval Author Preprint for Web  

E-Print Network [OSTI]

Web Information Retrieval Author Preprint for Web Nick Craswell and David Hawking 18 April 2009 1 Introduction This chapter outlines some distinctive characteristics of web information re- trieval, starting with a broad description of web data and the needs of web searching users, then working through ranking

Hawking, David

155

2, 10971130, 2002 Retrieval of water  

E-Print Network [OSTI]

ACPD 2, 1097­1130, 2002 Retrieval of water vapor columns R. Lang et al. Title Page Abstract, Amsterdam, The Netherlands 2 SRON National Institute for Space Research, Utrecht, The Netherlands 3 Department of Physics and Astronomy, Vrije Universiteit, Amsterdam, The Netherlands Received: 20 June 2002

Paris-Sud XI, Université de

156

Spare mitigation/retrieval mixer pumps  

SciTech Connect (OSTI)

This document presents the functional design criteria for design, analysis, fabrication, testing, and installation of a waste tank mixer pump. The mixer pump will be operated to eliminate the periodic releases of large quantities of flammable gas (e.g., hydrogen) from Hanford Site waste tanks and also to accommodate retrieval of tank waste.

Taylor, S.

1995-02-02T23:59:59.000Z

157

Strings on AdS wormholes  

SciTech Connect (OSTI)

We consider the behavior of open strings on anti-de Sitter wormholes in Gauss-Bonnet theory, which are the Gauss-Bonnet gravity duals of a pair of field theories. A string with both endpoints on the same side of the wormhole describes two charges within the same field theory, which exhibit Coulomb interaction for small separation. On the other hand, a string extending through the wormhole describes two charges which live in different field theories, and they exhibit a springlike confining potential. A transition occurs when there is a pair of charges present within each field theory: for small separation each pair of charges exhibits Coulomb interaction, while for large separation the charges in the different field theories pair up and exhibit confinement. Two steadily-moving charges in different field theories can occupy the same location provided that their speed is less than a critical speed, which also plays the role of a subluminal speed limit. However, for some wormhole backgrounds, charges moving at the critical speed cannot occupy the same location and energy is transferred from the leading charge to the lagging one. We also show that strings on anti-de Sitter wormholes in supergravity theories without higher-derivative curvature terms can exhibit these properties as well.

Ali, Mir; Ruiz, Frenny; Saint-Victor, Carlos [Physics Department, New York City College of Technology, City University of New York 300 Jay Street, Brooklyn, New York 11201 (United States); Vazquez-Poritz, Justin F. [Physics Department, New York City College of Technology, City University of New York 300 Jay Street, Brooklyn, New York 11201 (United States); Graduate School and University Center, City University of New York 365 Fifth Avenue, New York, New York 10016 (United States)

2009-08-15T23:59:59.000Z

158

Towards Dark Energy from String-Theory  

E-Print Network [OSTI]

We discuss vacuum energy in string and M-theory with a focus on heterotic M-theory. In the latter theory a mechanism is described for maintaining zero vacuum energy after supersymmetry breaking. Higher-order corrections can be expected to give a sufficiently small amount of vacuum energy to possibly account for dark energy.

Axel Krause

2008-03-12T23:59:59.000Z

159

Abelian-Higgs strings in Rastall gravity  

E-Print Network [OSTI]

In this paper we analyze Abelian-Higgs strings in a phenomenological model that takes quantum effects in curved space-time into account. This model, first introduced by Rastall, cannot be derived from an action principle. We formulate phenomenological equations of motion under the guiding principle of minimal possible deformation of the standard equations. We construct string solutions that asymptote to a flat space-time with a deficit angle by solving the set of coupled non-linear ordinary differential equations numerically. Decreasing the Rastall parameter from its Einstein gravity value we find that the deficit angle of the space-time increases and becomes equal to $2\\pi$ at some critical value of this parameter that depends on the remaining couplings in the model. For smaller values the resulting solutions are supermassive string solutions possessing a singularity at a finite distance from the string core. Assuming the Higgs boson mass to be on the order of the gauge boson mass we find that also in Rastall gravity this happens only when the symmetry breaking scale is on the order of the Planck mass. We also observe that for specific values of the parameters in the model the energy per unit length becomes proportional to the winding number, i.e. the degree of the map $S^1 \\rightarrow S^1$. Unlike in the BPS limit in Einstein gravity, this is, however, not connect to an underlying mathematical structure, but rather constitutes a would-be-BPS bound.

Eugenio R. Bezerra de Mello; Julio C. Fabris; Betti Hartmann

2015-04-02T23:59:59.000Z

160

The Cosmological Constant and the String Landscape  

E-Print Network [OSTI]

Theories of the cosmological constant fall into two classes, those in which the vacuum energy is fixed by the fundamental theory and those in which it is adjustable in some way. For each class we discuss key challenges. The string theory landscape is an example of an adjustment mechanism. We discuss the status of this idea, and future directions.

Joseph Polchinski

2006-04-21T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Kink in superconducting cosmic string: exact solution  

E-Print Network [OSTI]

We solve the equations of motion and find the Lorentz transformation associated with a kink in superconducting cosmic string. The kink velocity does not depend on its amplitude. The kink amplitude cannot be arbitrary but it varies within definite range and determines the explicit form of the relevant Lorentz transformation.

Ernst Trojan

2014-12-24T23:59:59.000Z

162

Thin Shell Wormhole in Heterotic String Theory  

E-Print Network [OSTI]

Using 'Cut and Paste' technique, we develop a thin shell wormhole in heterotic string theory. We determine the surface stresses, which are localized in the shell, by using Darmois-Israel formalism. The linearized stability of this thin wormhole is also analyzed.

F. Rahaman; M. Kalam; S. Chakraborti

2006-11-25T23:59:59.000Z

163

A Linear Storage-Retrieval Policy for Robust Warehouse Management  

E-Print Network [OSTI]

Nov 10, 2008 ... A Linear Storage-Retrieval Policy for Robust Warehouse Management ... Keywords: Dynamic programming, Transportation, Materials handling, ...

Marcus Ang

2008-11-10T23:59:59.000Z

164

Failed Retrieval of Potentially Retrievable IVC Filters: A Report of Two Cases  

SciTech Connect (OSTI)

Retrievable inferior vena cava filters are being increasingly used for the prevention of life-threatening pulmonary emboli in patients who have temporary contraindications to anticoagulation therapy. We report two cases of failure to remove these devices.

Kumar, Bangalore C. Anil [Queen's Medical Centre, Department of Radiology (United Kingdom)], E-mail: anil.kumar@doctors.org.uk; Chakraverty, Sam; Zealley, Ian [Ninewells Hospital, Department of Radiology (United Kingdom)

2006-02-15T23:59:59.000Z

165

Retrieval Success is Accompanied by Enhanced Activation in Anterior Prefrontal  

E-Print Network [OSTI]

and retrieval success. That is, we implemented a third condition in which nonstudied words were presented, yet) and thereby reject the lure. This method of instantiating retrieval success under conditions in whichRetrieval Success is Accompanied by Enhanced Activation in Anterior Prefrontal Cortex During

McDermott, Kathleen

166

Generalizing PIR for Practical Private Retrieval of Public Data  

E-Print Network [OSTI]

Generalizing PIR for Practical Private Retrieval of Public Data Shiyuan Wang, Divyakant Agrawal without revealing the query to the server. Computational Private Information Retrieval (cPIR) achieves approach for the pri- vate retrieval of public data called Bounding-Box PIR (bbPIR). Using bbPIR, a client

Boyer, Edmond

167

Refined Black Hole Ensembles and Topological Strings  

E-Print Network [OSTI]

We formulate a refined version of the Ooguri-Strominger-Vafa (OSV) conjecture. The OSV conjecture that Z_{BH} = |Z_{top}|^2 relates the BPS black hole partition function to the topological string partition function Z_{top}. In the refined conjecture, Z_{BH} is the partition function of BPS black holes counted with spin, or more precisely the protected spin character. Z_{top} becomes the partition function of the refined topological string, which is itself an index. Both the original and the refined conjecture are examples of large N duality in the 't Hooft sense. The refined conjecture applies to non-compact Calabi-Yau manifolds only, so the black holes are really BPS particles with large entropy, of order N^2. The refined OSV conjecture states that the refined BPS partition function has a large N dual which is captured by the refined topological string. We provide evidence that the conjecture holds by studying local Calabi-Yau threefolds consisting of line bundles over a genus g Riemann surface. We show that the refined topological string partition function on these geometries is computed by a two-dimensional TQFT. We also study the refined black hole partition function arising from N D4 branes on the Calabi-Yau, and argue that it reduces to a (q,t)-deformed version of two-dimensional SU(N) Yang-Mills. Finally, we show that in the large N limit this theory factorizes to the square of the refined topological string in accordance with the refined OSV conjecture.

Mina Aganagic; Kevin Schaeffer

2012-10-05T23:59:59.000Z

168

String dynamics and ejection along the axis of a spinning black hole  

E-Print Network [OSTI]

Relativistic current carrying strings moving axisymmetrically on the background of a Kerr black hole are studied. The boundaries and possible types of motion of a string with a given energy and current are found. Regions of parameters for which the string falls into the black hole, or is trapped in a toroidal volume, or can escape to infinity, are identified, and representative trajectories are examined by numerical integration, illustrating various interesting behaviors. In particular, we find that a string can start out at rest near the equatorial plane and, after bouncing around, be ejected out along the axis, some of its internal (elastic or rotational kinetic) energy having been transformed into translational kinetic energy. The resulting velocity can be an order unity fraction of the speed of light. This process results from the presence of an outer tension barrier and an inner angular momentum barrier that are deformed by the gravitational field. We speculatively discuss the possible astrophysical significance of this mechanism as a means of launching a collimated jet of MHD plasma flux tubes along the spin axis of a gravitating system fed by an accretion disk.

Ted Jacobson; Thomas P. Sotiriou

2009-03-26T23:59:59.000Z

169

Nonreciprocal wave scattering on nonlinear string-coupled oscillators  

E-Print Network [OSTI]

We study scattering of a periodic wave in a string on two lumped oscillators attached to it. The equations can be represented as a driven (by the incident wave) dissipative (due to radiation losses) system of delay differential equations of neutral type. Nonlinearity of oscillators makes the scattering non-reciprocal: the same wave is transmitted differently in two directions. Periodic regimes of scattering are analysed approximately, using amplitude equation approach. We show that this setup can act as a nonreciprocal modulator via Hopf bifurcations of the steady solutions. Numerical simulations of the full system reveal nontrivial regimes of quasiperiodic and chaotic scattering. Moreover, a regime of a "chaotic diode", where transmission is periodic in one direction and chaotic in the opposite one, is reported.

Stefano Lepri; Arkady Pikovsky

2014-10-29T23:59:59.000Z

170

Single-shell tank retrieval program mission analysis report  

SciTech Connect (OSTI)

This Mission Analysis Report was prepared to provide the foundation for the Single-Shell Tank (SST) Retrieval Program, a new program responsible for waste removal for the SSTS. The SST Retrieval Program is integrated with other Tank Waste Remediation System activities that provide the management, technical, and operations elements associated with planning and execution of SST and SST Farm retrieval and closure. This Mission Analysis Report provides the basis and strategy for developing a program plan for SST retrieval. This Mission Analysis Report responds to a US Department of Energy request for an alternative single-shell tank retrieval approach (Taylor 1997).

Stokes, W.J.

1998-08-11T23:59:59.000Z

171

Aerosol Retrievals from ARM SGP MFRSR Data  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The Multi-Filter Rotating Shadowband Radiometer (MFRSR) makes precise simultaneous measurements of the solar direct normal and diffuse horizontal irradiances at six wavelengths (nominally 415, 500, 615, 673, 870, and 940 nm) at short intervals (20 sec for ARM instruments) throughout the day. Time series of spectral optical depth are derived from these measurements. Besides water vapor at 940 nm, the other gaseous absorbers within the MFRSR channels are NO2 (at 415, 500, and 615 nm) and ozone (at 500, 615, and 670 nm). Aerosols and Rayleigh scattering contribute atmospheric extinction in all MFRSR channels. Our recently updated MFRSR data analysis algorithm allows us to partition the spectral aerosol optical depth into fine and coarse modes and to retrieve the fine mode effective radius. In this approach we rely on climatological amounts of NO2 from SCIAMACHY satellite retrievals and use daily ozone columns from TOMS.

Alexandrov, Mikhail

172

Bin Set 1 Calcine Retrieval Feasibility Study  

SciTech Connect (OSTI)

At the Department of Energy's Idaho Nuclear Technology and Engineering Center, as an interim waste management measure, both mixed high-level liquid waste and sodium bearing waste have been solidified by a calculation process and are stored in the Calcine Solids Storage Facilities. This calcined product will eventually be treated to allow final disposal in a national geologic repository. The Calcine Solids Storage Facilities comprise seven ''bit sets.'' Bin Set 1, the first to be constructed, was completed in 1959, and has been in service since 1963. It is the only bin set that does not meet current safe-shutdown earthquake seismic criteria. In addition, it is the only bin set that lacks built-in features to aid in calcine retrieval. One option to alleviate the seismic compliance issue is to transport the calcine from Bin Set 1 to another bin set which has the required capacity and which is seismically qualified. This report studies the feasibility of retrieving the calcine from Bi n Set 1 and transporting it into Bin Set 6 which is located approximately 650 feet away. Because Bin Set 1 was not designed for calcine retrieval, and because of the high radiation levels and potential contamination spread from the calcined material, this is a challenging engineering task. This report presents preconceptual design studies for remotely-operated, low-density, pneumatic vacuum retrieval and transport systems and equipment that are based on past work performed by the Raytheon Engineers and Constructors architectural engineering firm. The designs presented are considered feasible; however, future development work will be needed in several areas during the subsequent conceptual design phase.

R. D. Adams; S. M. Berry; K. J. Galloway; T. A. Langenwalter; D. A. Lopez; C. M. Noakes; H. K. Peterson; M. I. Pope; R. J. Turk

1999-10-01T23:59:59.000Z

173

Signal connection for a downhole tool string  

DOE Patents [OSTI]

A signal transmission connection for a tool string used in exploration and production of natural resources, namely: oil, gas, and geothermal energy resources. The connection comprises first and second annular elements deployed in cooperative association with each other. The respective elements comprise inductive transducers that are capable of two-way signal transmission between each other, with downhole components of the tool string, and with ground-level equipment. The respective inductive transducers comprise one or more conductive loops housed within ferrite troughs, or within ferrite trough segments. When energized, the conductive loops produce a magnetic field suitable for transmitting the signal. The second element may be rotational in drilling applications. The respective elements may be fitted with electronic equipment to aid and manipulate the transmission of the signal. The first element may also be in communication with the World Wide Web.

Hall, David R.; Hall Jr., H. Tracy; Pixton, David S.; Bradford, Kline; Fox, Joe; Briscoe, Michael

2006-08-29T23:59:59.000Z

174

Vacuum Selection on the String Landscape  

E-Print Network [OSTI]

I examine some non-anthropic approaches to the string landscape. These approaches are based on finding the initial conditions of the universe using the wavefunction of the multiverse to select the most probable vacuum out of this landscape. All approaches tackled so far seems to have their own problems and there is no clear cut alternative to anthropic reasoning. I suggest that finding the initial conditions may be irrelevant since all possible vacua on the landscape are possible initial state conditions and eternal inflation could generate all the other vacua. We are now left to reason out why we are observing the small value of the cosmological constant (CC). I address this issue in the contest of noncritical string theory in which all values of the cosmological constant on the landscape are departures from critical equilibrium state.

Edward Tetteh-Lartey

2007-05-08T23:59:59.000Z

175

An Algorithmic Approach to Heterotic String Phenomenology  

E-Print Network [OSTI]

We briefly review the recent programme to construct, systematically and algorithmically, large classes of heterotic vacua, as well as the search for the MSSM therein. Specifically, we outline the monad construction of vector bundles over complete intersection Calabi-Yau threefolds, their classification, stability, equivariant cohomology and subsequent relevance to string phenomenology. It is hoped that this top-down algorithmic approach will isolate special corners in the heterotic landscape.

Yang-Hui He

2010-01-14T23:59:59.000Z

176

Traversable wormholes in a string cloud  

E-Print Network [OSTI]

We study spherically symmetric thin-shell wormholes in a string cloud background in (3+1)-dimensional spacetime. The amount of exotic matter required for the construction, the traversability and the stability under radial perturbations, are analyzed as functions of the parameters of the model. Besides, in the Appendices a non perturbative approach to the dynamics and a possible extension of the analysis to a related model are briefly discussed.

Martin Richarte; Claudio Simeone

2007-11-14T23:59:59.000Z

177

Gapless superconductivity and string theory  

E-Print Network [OSTI]

Coexistence of superconducting and normal components in nanowires at currents below the critical (a "mixed" state) would have important consequences for the nature and range of potential applications of these systems. For clean samples, it represents a genuine interaction effect, not seen in the mean-field theory. Here we consider properties of such a state in the gravity dual of a strongly coupled superconductor constructed from D3 and D5 branes. We find numerically uniform gapless solutions containing both components but argue that they are unstable against phase separation, as their free energies are not convex. We speculate on the possible nature of the resulting non-uniform sate ("emulsion") and draw analogies between that state and the familiar mixed state of a type II superconductor in a magnetic field.

Sergei Khlebnikov

2014-11-06T23:59:59.000Z

178

Non static local string in Brans-Dicke theory  

E-Print Network [OSTI]

A recent investigation shows that a local gauge string with a phenomenological energy momentum tensor, as prescribed by Vilenkin, is inconsistent in Brans-Dicke theory. In this work, it has been shown that such a string is indeed consistent if one introduces time dependences in the metric. A set of solutions of full nonlinear Einstein's equations for the interior region of such a string are presented.

A. A. Sen

1998-03-09T23:59:59.000Z

179

Local cosmic string in generalised scalar tensor theory  

E-Print Network [OSTI]

A recent investigation shows that a local gauge string with a phenomenological energy momentum tensor, as prescribed by Vilenkin, is inconsistent in Brans-Dicke theory. In this work it has been shown that such a string is consistent in a more general scalar tensor theory where $\\omega$ is function of the scalar field.A set of solutions of full nonlinear Einstein's equations for interior region of such a string are presented.

A. A. Sen; N. Banerjee

1998-02-25T23:59:59.000Z

180

Exact entanglement renormalization for string-net models  

E-Print Network [OSTI]

We construct an explicit renormalization group (RG) transformation for Levin and Wen's string-net models on a hexagonal lattice. The transformation leaves invariant the ground-state "fixed-point" wave function of the string-net condensed phase. Our construction also produces an exact representation of the wave function in terms of the multi-scale entanglement renormalization ansatz (MERA). This sets the stage for efficient numerical simulations of string-net models using MERA algorithms. It also provides an explicit quantum circuit to prepare the string-net ground-state wave function using a quantum computer.

Robert Koenig; Ben W. Reichardt; Guifre Vidal

2009-06-15T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

The Hubble Web: The Dark Matter Problem and Cosmic Strings  

SciTech Connect (OSTI)

I propose a reinterpretation of cosmic dark matter in which a rigid network of cosmic strings formed at the end of inflation. The cosmic strings fulfill three functions: At recombination they provide an accretion mechanism for virializing baryonic and warm dark matter into disks. These cosmic strings survive as configurations which thread spiral and elliptical galaxies leading to the observed flatness of rotation curves and the Tully-Fisher relation. We find a relationship between the rotational velocity of the galaxy and the string tension and discuss the testability of this model.

Alexander, Stephon [Departments of Physics and Astronomy, Institute for Gravity and Geometry, Pennsylvania State University, University Park, PA 16802 (United States)

2009-07-06T23:59:59.000Z

182

The Hubble Web: The Dark Matter Problem and Cosmic Strings  

E-Print Network [OSTI]

I propose a reinterpretation of cosmic dark matter in which a rigid network of cosmic strings formed at the end of inflation. The cosmic strings fulfill three functions: At recombination they provide an accretion mechanism for virializing baryonic and warm dark matter into disks. These cosmic strings survive as configurations which thread spiral and elliptical galaxies leading to the observed flatness of rotation curves and the Tully-Fisher relation. We find a relationship between the rotational velocity of the galaxy and the string tension and discuss the testability of this model.

Stephon Alexander

2007-02-27T23:59:59.000Z

183

An Investigation of Subword Unit Representations for Spoken Document Retrieval  

E-Print Network [OSTI]

An Investigation of Subword Unit Representations for Spoken Document Retrieval Kenney Ng and Victor W. Zue Spoken Language Systems Group MIT Laboratory for Computer Science 545 Technology Square

184

Water Retrieval by Norway Rats: Behavior as Deduction  

E-Print Network [OSTI]

1948). Burrows and feeding of the Norway a radial Mammalogy,Object retrieval preferences of Norway rats: An evolutionaryinedible objects by Norway rats: Motivational interactions

Wallace, R J

1998-01-01T23:59:59.000Z

185

X-1 ROEBELING ET AL.: SEVIRI & AVHRR CLOUD PROPERTY RETRIEVALS Cloud property retrievals for climate monitoring  

E-Print Network [OSTI]

Generation (METEOSAT-8) and the Advanced Very High Resolution Radiometer (AVHRR) onboard the National Oceanic a consistent and high quality dataset of SEVIRI and AVHRR retrieved cloud properties for climate research studies. Clouds strongly modulate the energy balance of the Earth and its atmosphere through

Stoffelen, Ad

186

Light $U(1)$s in heterotic string models  

E-Print Network [OSTI]

We present a novel string-derived $U(1)$ combination that satisfies necessary properties to survive to low scales. We discuss previous attempts at acquiring such an abelian gauge symmetry from two different string embeddings and the pitfalls associated with them. Finally, we give an example of how a satisfactory model may be constructed within our framework.

Mehta, Viraf M

2015-01-01T23:59:59.000Z

187

Peculiarities in the energy transfer by waves on strained strings  

E-Print Network [OSTI]

Peculiarities in the energy transfer by waves on strained strings Eugene I. Butikov St. Petersburg of elastic potential energy associated with waves in a stretched string is discussed. The influence of nonlinear coupling between transverse and longitudinal waves on the density of energy is investigated

Butikov, Eugene

188

From string theory to algebraic geometry and back  

SciTech Connect (OSTI)

We describe some facts in physics which go up to the modern string theory and the related concepts in algebraic geometry. Then we present some recent results on moduli-spaces of vector bundles on non-Kaehler Calabi-Yau 3-folds and their consequences for heterotic string theory.

Brinzanescu, Vasile ['Simion Stoilow' Institute of Mathematics of the Romanian Academy, P.O.Box 1-764, Bucharest (Romania)

2011-02-10T23:59:59.000Z

189

Resonant acoustic transducer system for a well drilling string  

DOE Patents [OSTI]

For use in transmitting acoustic waves propated along a well drilling string, a piezoelectric transducer is provided operating in the relatively low loss acoustic propagation range of the well drilling string. The efficiently coupled transmitting transducer incorporates a mass-spring-piezoelectric transmitter combination permitting a resonant operation in the desired low frequency range.

Nardi, Anthony P. (Burlington, MA)

1981-01-01T23:59:59.000Z

190

Resonant acoustic transducer system for a well drilling string  

DOE Patents [OSTI]

For use in transmitting acoustic waves propagated along a well drilling string, a piezoelectric transducer is provided operating in the relatively low loss acoustic propagation range of the well drilling string. The efficiently coupled transmitting transducer incorporates a mass-spring-piezoelectric transmitter combination permitting resonant operation in the desired low frequency range.

Kent, William H. (Westford, MA); Mitchell, Peter G. (Concord, MA)

1981-01-01T23:59:59.000Z

191

Vacuumless cosmic strings in Brans-Dicke theory  

E-Print Network [OSTI]

The gravitational fields of vacuumless global and gauge strings have been studied in Brans-Dicke theory under the weak field assumption of the field equations. It has been shown that both global and gauge string can have repulsive as well as attractive gravitational effect in Brans-Dicke theory which is not so in General Relativity.

A. A. Sen

2000-02-13T23:59:59.000Z

192

Dynamics of a self-gravitating thin cosmic string  

E-Print Network [OSTI]

We assume that a self-gravitating thin string can be locally described by what we shall call a smoothed cone. If we impose a specific constraint on the model of the string, then its central line obeys the Nambu-Goto equations. If no constraint is added, then the worldsheet of the central line is a totally geodesic surface.

B. Boisseau; C. Charmousis; B. Linet

1997-02-06T23:59:59.000Z

193

On the Early Tension between String Theory and Phenomenology  

E-Print Network [OSTI]

On the Early Tension between String Theory and Phenomenology L. Clavelli Department of Physics noticeable tension between string theory and phenomenology in particle physics. It is interesting to muse theory and phenomenology is more easily understandable than that of the early days. Today it is primarily

Clavelli, Louis J.

194

Character String Predicate Based Automatic Software Test Data Generation  

E-Print Network [OSTI]

Character String Predicate Based Automatic Software Test Data Generation Ruilian Zhao Computer is an important element in programming. A problem that needs further research is how to automatically generate generation of program paths including character string predicates, and the effectiveness of this approach

Lyu, Michael R.

195

Small Waste Tank Sampling and Retrieval System  

SciTech Connect (OSTI)

At the Test Reactor Area of the Idaho National Engineering and Environmental Laboratory (INEEL), four 1500-gal catch tanks were found to contain RCRAhazardous waste. A system was needed to obtain a representative sample of the liquid, as well as the hardpacked heels, and to ultimately homogenize and remove the tank contents for disposal. After surveying the available technologies, the AEA Fluidic Pulse Mixing and Retrieval System was chosen for a technology demonstration. A demonstration, conducted with nonhazardous surrogate material, proved that the system was capable of loosening the hard-packed heel, homogenizing the entire tank contents, and collecting a representative sample. Based on the success of the demonstration, a detailed evaluation was done to determine the applicability of the system to other tanks. The evaluation included the sorting of data on more than 700 tanks to select candidates for further deployment of the system. A detailed study was also done to determine if the purchase of a second system would be cost effective. The results of the evaluation indicated that a total of thirteen tanks at the INEEL are amenable to sampling and/or remediation using the AEA Fluidic Pulse Mixing and Retrieval System. Although the currently-owned system appears sufficient for the needs of one INEEL program, it is insufficient to meet the combined needs at the INEEL. The INEEL will commence operation of the system on the TRA-730 Catch Tank System in June 2002.

Magleby, Mary Theresa

2002-08-01T23:59:59.000Z

196

Quantum computational tensor network on string-net condensate  

E-Print Network [OSTI]

The string-net condensate is a new class of materials which exhibits the quantum topological order. In order to answer the important question, "how useful is the string-net condensate in quantum information processing?", we consider the most basic example of the string-net condensate, namely the $Z_2$ gauge string-net condensate on the two-dimensional hexagonal lattice, and show that the universal measurement-based quantum computation (in the sense of the quantum computational webs) is possible on it by using the framework of the quantum computational tensor network. This result implies that even the most basic example of the string-net condensate is equipped with the correlation space that has the capacity for the universal quantum computation.

Tomoyuki Morimae

2011-09-27T23:59:59.000Z

197

The Normalization of Perturbative String Amplitudes: Weyl Covariance and Zeta Function Regularization  

E-Print Network [OSTI]

This is a self-contained pedagogical review of Polchinski's 1986 analysis from first principles of the Polyakov path integral based on Hawking's zeta function regularization technique for scale-invariant computations in two-dimensional quantum gravity, an approach that can be adapted to any of the perturbative string theories. In particular, we point out the physical significance of preserving both Weyl and global diffeomorphism invariance while taking the low energy field theory limit of scattering amplitudes in an open and closed string theory, giving a brief discussion of some physics applications. We review the path integral computation of the pointlike off-shell closed bosonic string propagator due to Cohen, Moore, Nelson, and Polchinski. The extension of their methodology to the case of the macroscopic loop propagator in an embedding flat spacetime geometry has been given by Chaudhuri, Chen, and Novak. We examine the macroscopic loop amplitude from the perspective of both the target spacetime massive type II supergravity theory, and the boundary state formalism of the worldsheet conformal field theory, clarifying the precise evidence it provides for a Dirichlet (-2)brane, an identification made by Chaudhuri. The appendices contain extensive detail.

Shyamoli Chaudhuri

2005-03-02T23:59:59.000Z

198

Aho-Corasick String Matching on Shared and Distributed Memory Parallel Architectures  

SciTech Connect (OSTI)

String matching is at the core of many critical applications, including network intrusion detection systems, search engines, virus scanners, spam filters, DNA and protein sequencing, and data mining. For all of these applications string matching requires a combination of (sometimes all) the following characteristics: high and/or predictable performance, support for large data sets and flexibility of integration and customization. Many software based implementations targeting conventional cache-based microprocessors fail to achieve high and predictable performance requirements, while Field-Programmable Gate Array (FPGA) implementations and dedicated hardware solutions fail to support large data sets (dictionary sizes) and are difficult to integrate and customize. The advent of multicore, multithreaded, and GPU-based systems is opening the possibility for software based solutions to reach very high performance at a sustained rate. This paper compares several software-based implementations of the Aho-Corasick string searching algorithm for high performance systems. We discuss the implementation of the algorithm on several types of shared-memory high-performance architectures (Niagara 2, large x86 SMPs and Cray XMT), distributed memory with homogeneous processing elements (InfiniBand cluster of x86 multicores) and heterogeneous processing elements (InfiniBand cluster of x86 multicores with NVIDIA Tesla C10 GPUs). We describe in detail how each solution achieves the objectives of supporting large dictionaries, sustaining high performance, and enabling customization and flexibility using various data sets.

Tumeo, Antonino; Villa, Oreste; Chavarría-Miranda, Daniel

2012-03-01T23:59:59.000Z

199

Location Coding for Mobile Image Retrieval Sam S. Tsai  

E-Print Network [OSTI]

Location Coding for Mobile Image Retrieval Sam S. Tsai , David Chen , Gabriel Takacs , Vijay, gtakacs, vijayc, bgirod}@stanford.edu, jatinder.singh@telekom.de ABSTRACT For mobile image retrieval images using a "bag-of-words" approach while the latter is used in a geometric consistency check to map

Girod, Bernd

200

Societal Research Archives System : Retrieval, quality control and analysis  

E-Print Network [OSTI]

Societal Research Archives System : Retrieval, quality control and analysis of comparative data sample selection and data retrieval to correlation, data quality control, and testing for genetic, and White, 1967a). This represents 40 % of the approximate total number of such publications, but over 90

White, Douglas R.

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Conceptual modelling for domain specific document description and retrieval  

E-Print Network [OSTI]

and are applied in the tasks of describing and retrieving documents, within cooperative document management settings, where the users themselves have to perform the document management tasks they need in orderConceptual modelling for domain specific document description and retrieval - An approach

202

Content-Based Document Image Retrieval in Complex Document Collections  

E-Print Network [OSTI]

Content-Based Document Image Retrieval in Complex Document Collections G. Agama, S. Argamona, O address the problem of content-based image retrieval in the context of complex document images. Complex document are documents that typically start out on paper and are then electronically scanned. These docu

203

8, 42674308, 2008 3-D retrieval of cloud  

E-Print Network [OSTI]

ACPD 8, 4267­4308, 2008 3-D retrieval of cloud particle profiles T. Zinner et al. Title Page.0 License. Atmospheric Chemistry and Physics Discussions Remote sensing of cloud sides of deep convection: towards a three-dimensional retrieval of cloud particle size profiles T. Zinner 1,2 , A. Marshak 1 , S

Paris-Sud XI, Université de

204

PIRMAP: Efficient Private Information Retrieval for MapReduce  

E-Print Network [OSTI]

{travism,blass,ahchan}@ccs.neu.edu Abstract. Private Information Retrieval (PIR) allows a user to retrieve bits from a database while hiding the user's access pattern. However, the practicality of PIR in a real-world cloud computing setting has recently been questioned. In such a setting, PIR's enormous computation

205

A Random Server Model for Private Information Retrieval or  

E-Print Network [OSTI]

model for PIR (or SPIR), which allows us to achieve significant improvements both in terms of securityA Random Server Model for Private Information Retrieval or How to Achieve Information Theoretic PIR, Cambridge, MA 02139, USA fshafi,talg@theory.lcs.mit.edu Abstract. Private information retrieval (PIR

Goldwasser, Shafi

206

Efficient Computationally Private Information Retrieval From Anonymity or Trapdoor Groups  

E-Print Network [OSTI]

family of cPIR protocols with a variety of security and performance properties. Our protocols enable much. Laurel, MD 20723 Abstract A Private Information Retrieval (PIR) protocol allows a database user data was retrieved. Although substantial progress has been made in the discovery of computationally PIR

207

Private Information Retrieval An overview and current trends  

E-Print Network [OSTI]

a server was not considered feasible until the private infor- mation retrieval (PIR) problem was stated recently. A PIR protocol allows a user to retrieve a record from a database while hiding the identity of the record from a database server. We explain a motivation for PIR by demonstrating e- commerce examples

Freytag, Johann-Christoph

208

3D Model Retrieval based on Adaptive Views Clustering  

E-Print Network [OSTI]

3D Model Retrieval based on Adaptive Views Clustering Tarik Filali Ansary1 , Mohamed Daoudi2 , Jean.daoudi@univ-tours.fr http://www-rech.enic.fr/miire Abstract. In this paper, we propose a method for 3D model indexing based selection of 2D views from a 3D model, and a probabilistic Bayesian method for 3D model retrieval from

Paris-Sud XI, Université de

209

Retrieval of ozone and nitrogen dioxide concentrations from Stratospheric Aerosol and Gas Experiment III (SAGE III)  

E-Print Network [OSTI]

Retrieval of ozone and nitrogen dioxide concentrations from Stratospheric Aerosol and Gas extinction. We retrieve ozone and nitrogen dioxide number densities and aerosol extinction from transmission), Retrieval of ozone and nitrogen dioxide concentrations from Stratospheric Aerosol and Gas Experiment III

210

Satellite observations of ozone and nitrogen dioxide: from retrievals to emission estimates  

E-Print Network [OSTI]

Satellite observations of ozone and nitrogen dioxide: from retrievals to emission estimates #12 Satellite observations of ozone and nitrogen dioxide: from retrievals to emission es- timates / by Bas Subject headings: satellite retrieval / nitrogen dioxide / ozone / air pollution / emis- sion estimates

Haak, Hein

211

Techniques for Intravascular Foreign Body Retrieval  

SciTech Connect (OSTI)

As endovascular therapies increase in frequency, the incidence of lost or embolized foreign bodies is increasing. The presence of an intravascular foreign body (IFB) is well recognized to have the potential to cause serious complications. IFB can embolize and impact critical sites such as the heart, with subsequent significant morbidity or mortality. Intravascular foreign bodies most commonly result from embolized central line fragments, but they can originate from many sources, both iatrogenic and noniatrogenic. The percutaneous approach in removing an IFB is widely perceived as the best way to retrieve endovascular foreign bodies. This minimally invasive approach has a high success rate with a low associated morbidity, and it avoids the complications related to open surgical approaches. We examined the characteristics, causes, and incidence of endovascular embolizations and reviewed the various described techniques that have been used to facilitate subsequent explantation of such materials.

Woodhouse, Joe B.; Uberoi, Raman, E-mail: raman.uberoi@orh.nhs.uk [Oxford University Hospitals (United Kingdom)

2013-08-01T23:59:59.000Z

212

Satellite Multiangle Cumulus Geometry Retrieval: Case Study  

SciTech Connect (OSTI)

Most satellite-based analyses have been conducted using near nadir-viewing sensors. The Multi-angle Imaging SpectroRadiometer (MISR), recently launched on the National Aeronautics and Space Administration (NASA) Terra platform, provides high-resolution measurements of reflectance at nine different viewing angles. In this study, we examine the possible retrieval of detailed cumulus geometry using the new and unique MISR datasets. We suggested one approach and apply it to an early MISR dataset of small marine cumulus clouds. This paper also presents validation analysis of this technique with both independent ground-based radar measurements and a model-output inverse problem. Collocated and coincident MISR data and ground-based observations at the Atmospheric Radiation Measurement (ARM) Tropical Western Pacific (TWP) site form the basis of this validation. Future work will attempt to test the suggested approach with additional MISR scenes.

Kassianov, Evgueni I.; Ackerman, Thomas P.; Marchand, Roger T.; Ovtchinnikov, Mikhail

2003-02-08T23:59:59.000Z

213

FRACTAL STRINGS AND MULTIFRACTAL ZETA MICHEL L. LAPIDUS, JACQUES LEVY-VEHEL  

E-Print Network [OSTI]

FRACTAL STRINGS AND MULTIFRACTAL ZETA FUNCTIONS MICHEL L. LAPIDUS, JACQUES L´EVY-V´EHEL AND JOHN A and the geometric zeta functions of fractal strings. The parameter value recovers the geometric zeta function func- tion of a fractal string, providing information on the structure of a given string in addition

Paris-Sud XI, Université de

214

Random fractal strings: their zeta functions, complex dimensions and spectral asymptotics  

E-Print Network [OSTI]

Random fractal strings: their zeta functions, complex dimensions and spectral asymptotics B-increasing real numbers which sums to one. For our purposes a fractal string is a string formed from the lengths versions of fractal strings. We show that using a random re- cursive self-similar construction

Jordan, Jonathan

215

Storage and retrieval of large digital images  

DOE Patents [OSTI]

Image compression and viewing are implemented with (1) a method for performing DWT-based compression on a large digital image with a computer system possessing a two-level system of memory and (2) a method for selectively viewing areas of the image from its compressed representation at multiple resolutions and, if desired, in a client-server environment. The compression of a large digital image I(x,y) is accomplished by first defining a plurality of discrete tile image data subsets T.sub.ij (x,y) that, upon superposition, form the complete set of image data I(x,y). A seamless wavelet-based compression process is effected on I(x,y) that is comprised of successively inputting the tiles T.sub.ij (x,y) in a selected sequence to a DWT routine, and storing the resulting DWT coefficients in a first primary memory. These coefficients are periodically compressed and transferred to a secondary memory to maintain sufficient memory in the primary memory for data processing. The sequence of DWT operations on the tiles T.sub.ij (x,y) effectively calculates a seamless DWT of I(x,y). Data retrieval consists of specifying a resolution and a region of I(x,y) for display. The subset of stored DWT coefficients corresponding to each requested scene is determined and then decompressed for input to an inverse DWT, the output of which forms the image display. The repeated process whereby image views are specified may take the form an interaction with a computer pointing device on an image display from a previous retrieval.

Bradley, Jonathan N. (Los Alamos, NM)

1998-01-01T23:59:59.000Z

216

Storage and retrieval of large digital images  

DOE Patents [OSTI]

Image compression and viewing are implemented with (1) a method for performing DWT-based compression on a large digital image with a computer system possessing a two-level system of memory and (2) a method for selectively viewing areas of the image from its compressed representation at multiple resolutions and, if desired, in a client-server environment. The compression of a large digital image I(x,y) is accomplished by first defining a plurality of discrete tile image data subsets T{sub ij}(x,y) that, upon superposition, form the complete set of image data I(x,y). A seamless wavelet-based compression process is effected on I(x,y) that is comprised of successively inputting the tiles T{sub ij}(x,y) in a selected sequence to a DWT routine, and storing the resulting DWT coefficients in a first primary memory. These coefficients are periodically compressed and transferred to a secondary memory to maintain sufficient memory in the primary memory for data processing. The sequence of DWT operations on the tiles T{sub ij}(x,y) effectively calculates a seamless DWT of I(x,y). Data retrieval consists of specifying a resolution and a region of I(x,y) for display. The subset of stored DWT coefficients corresponding to each requested scene is determined and then decompressed for input to an inverse DWT, the output of which forms the image display. The repeated process whereby image views are specified may take the form an interaction with a computer pointing device on an image display from a previous retrieval. 6 figs.

Bradley, J.N.

1998-01-20T23:59:59.000Z

217

Hydraulic drill string breakdown and bleed off unit  

SciTech Connect (OSTI)

An apparatus is described for use within an oil well rig for decoupling a tubing string into pipe segments comprising, in combination: rotary tong means for applying an unthreading torque to a first, upper pipe segment within the tubing string; torque resisting means for securing a second, lower pipe segment within the tubing string against the unthreading torque; containing means, intermediate the rotary tong means and the torque resisting means, enclosing a threaded joint of the tubing string, adapted for containing pressurized gases, liquids, and particulates, released from the threaded joint upon the decoupling; fluid communicating means for allowing fluid communication between the containing means and a receiving point adapted for receiving the pressurized gases, liquids, and particulates; means for moving the rotary tong means, the torque resisting means and the containing means between a closed, engaging position with the tubing string and an open position; and means for horizontally moving the rotary tong means, the torque resisting means and the containing means between a position adjacent the tubing string and a position away from the tubing string.

Zeringue, F.J. Jr.

1987-02-17T23:59:59.000Z

218

Cosmic string formation and the power spectrum of field configurations  

E-Print Network [OSTI]

We examine the statistical properties of defects formed by the breaking of a U(1) symmetry when the Higgs field has a power spectrum $P(k) \\propto k^n$. We find a marked dependence of the amount of infinite string on the spectral index $n$ and empirically identify an analytic form for this quantity. We also confirm that this result is robust to changes in the definition of infinite string. It is possible that this result could account for the apparent absence of infinite string in recent lattice-free simulations.

James Robinson; Andrew Yates

1996-06-12T23:59:59.000Z

219

Accretion onto a black hole in a string cloud background  

E-Print Network [OSTI]

We examine the accretion process onto the black hole with a string cloud background, where the horizon of the black hole has an enlarged radius $r_H=2 M/(1-\\alpha)$, due to the string cloud parameter $\\alpha\\; (0 \\leq \\alpha cloud parameter $\\alpha$. We also find the gas compression ratios and temperature profiles below the accretion radius and at the event horizon. It is shown that the mass accretion rate, for both the relativistic and the non-relativistic fluid by a black hole in the string cloud model, increases with increase in $\\alpha$.

Apratim Ganguly; Sushant G. Ghosh; Sunil D. Maharaj

2014-09-28T23:59:59.000Z

220

Dynamics of a global string with large Higgs boson mass  

E-Print Network [OSTI]

We consider a self-gravitating string generated by a global vortex solution in general relativity. We investigate the Einstein and field equations of a global vortex in the region of its central line and at a distance from the centre of the order of the inverse of its Higgs boson mass. By combining the two we establish by a limiting process of large Higgs mass the dynamics of a self-gravitating global string. Under our assumptions the presence of gravitation restricts the world sheet of the global string to be totally geodesic.

C. Charmousis; B. Boisseau; B. Linet

1998-01-12T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Harmonic coordinates in the string and membrane equations  

E-Print Network [OSTI]

In this note, we first show that the solutions to Cauchy problems for two versions of relativistic string and membrane equations are diffeomorphic. Then we investigate the coordinates transformation presented in Ref. [9] (see (2.20) in Ref. [9]) which plays an important role in the study on the dynamics of the motion of string in Minkowski space. This kind of transformed coordinates are harmonic coordinates, and the nonlinear relativistic string equations can be straightforwardly simplified into linear wave equations under this transformation.

Chun-Lei He; Shou-Jun Huang

2010-04-16T23:59:59.000Z

222

Conformable apparatus in a drill string  

DOE Patents [OSTI]

An apparatus in a drill string comprises an internally upset drill pipe. The drill pipe comprises a first end, a second end, and an elongate tube intermediate the first and second ends. The elongate tube and the ends comprising a continuous an inside surface with a plurality of diameters. A conformable metal tube is disposed within the drill pipe intermediate the ends thereof and terminating adjacent to the ends of the drill pipe. The conformable metal tube substantially conforms to the continuous inside surface of the metal tube. The metal tube may comprise a non-uniform section which is expanded to conform to the inside surface of the drill pipe. The non-uniform section may comprise protrusions selected from the group consisting of convolutions, corrugations, flutes, and dimples. The non-uniform section extends generally longitudinally along the length of the tube. The metal tube may be adapted to stretch as the drill pipes stretch.

Hall, David R. (Provo, UT); Hall, Jr., H. Tracy (Provo, UT); Pixton, David S. (Lehi, UT); Fox, Joe (Spanish Fork, UT)

2007-08-28T23:59:59.000Z

223

Light superconducting strings in the Galaxy  

E-Print Network [OSTI]

Observations of the Milky Way by the SPI/INTEGRAL satellite have confirmed the presence of a strong 511 KeV gamma-ray line emission from the bulge, which require an intense source of positrons in the galactic center. These observations are hard to account for by conventional astrophysical scenarios, whereas other proposals, such as light DM, face stringent constraints from the diffuse gamma-ray background. Here we suggest that light superconducting strings could be the source of the observed 511 KeV emission. The associated particle physics, at the ~ 1 TeV scale, is within reach of planned accelerator experiments, while the distinguishing spatial distribution, proportional to the galactic magnetic field, could be mapped by SPI or by future, more sensitive, satellite missions.

Francesc Ferrer; Tanmay Vachaspati

2006-08-08T23:59:59.000Z

224

Apparatus for stringing well pipe of casing  

SciTech Connect (OSTI)

An apparatus for use in running a string of threaded well pipe or casing in a vertical configuration in a deep well bore which is adapted to convert a top head drive drilling rig for use in running each length of pipe into the well bore. A drive spindle adaptor is provided which may be securely attached in a removably mounted manner to the rotary drive spindle or sub of a top head drive drilling rig. The drive spindle includes a pair of opposing, outwardly extending lugs disposed at a right angle to the axial direction of the spindle and a true centering guide means. A collar is included which is provided with frictional gripping members for removably securing the collar to one end of a length of conventional pipe and a pair of axially extending, spaced ears which cooperate upon engagement with said lugs on said spindle adaptor to transfer rotary motion of said spindle to said length of pipe.

Sexton, J.L.

1984-04-17T23:59:59.000Z

225

Neighboring Valley in the String Landscape  

E-Print Network [OSTI]

The observation in the universe of a small but positive vacuum energy strongly suggests, in the string landscape picture, that there will ultimately be a phase transition to an exactly supersymmetric universe. This ground state or "true vacuum" of the universe could be similar to the minimal supersymmetric standard model with all the susy breaking parameters set to zero. Alternatively, it might be similar to the prominent superstring theories with nine flat space dimensions or to the supersymmetric anti-deSitter model that seems to be equivalent to a conformal field theory. We propose that the dominant phenomenological feature of these potential future universes is the weakening of the Pauli principle due to Fermi-Bose degeneracy. Providing the phase transition occurs in the cosmologically near future, an exact supersymmetry could extend the life expectancy of intelligent civilizations far beyond what would be possible in the broken susy universe.

L. Clavelli

2006-07-03T23:59:59.000Z

226

Gravitating non-Abelian cosmic strings  

E-Print Network [OSTI]

In this paper we study regular cosmic string solutions of the non-Abelian Higgs model coupled with the Einstein gravity. In order to do that, we constructed a set of coupled differential ordinary equation. Because there is no closed solution for this set of equations, we solve it numerically. The solutions that we are interested in asymptote to a flat space-time with a planar angle deficit. This model under consideration present two bosonic sectors, besides the non-Abelian gauge one, coupled minimally with the gravitational fields. The two bosonic sectors may present a direct coupling, which plays an important role on the behavior of the matter and gauge fields and also on the behavior on the geometry of the spacetime. We explicitly analyze the behaviors of the energy density and planar angle deficit as function of the energy scale where the gauge symmetry is spontaneously broken and the coupling interaction between the bosonic sectors.

Santo, Antônio de Padua

2015-01-01T23:59:59.000Z

227

Euclidean spinor Green's functions in the spacetime of a straight cosmic string  

E-Print Network [OSTI]

We determine generally the spinor Green's function and the twisted spinor Green's function in an Euclidean space with a conical-type line singularity. In particular, in the neighbourhood of the point source, we expree them as a sum of the usual Euclidean spinor Green's functin and a regular term. In four dimensions, we use these determinations to calculate the vacuum energy density and the twisted one for a massless spinor field in the spacetime of a straight cosmic string. In the Minkowski spacetime, we determine explicitly the vacuum energy density for a massive twisted spinor field.

B. Linet

1994-12-19T23:59:59.000Z

228

The Effect of Supercritical String Cosmology on the Relic Density of Dark Matter  

E-Print Network [OSTI]

. 3 As various type Ia supernovae projects [4,5] and the WMAP data [1,2] have continually confirmed the existence of dark energy, the cause of universe expansion, Supercritical String Cosmology (SSC) [6,7] arises as a model attempting to formulate... imply that exotic matter has negative pressure, acting like a dark energy term. Also, notice that the factor R increases as ?? decreases. When ?? = 0, ???? = 3.8 ? 1014. Such high enhancement factor is obviously ruled out by observational data, so...

Truong, Phuongmai N

2009-06-09T23:59:59.000Z

229

LHC Olympics Workshop and String Phenomenology 2006 Conference  

SciTech Connect (OSTI)

This is the final report of the organizers of the String Phenomenolgy program of which the LHC Olympics and the String Phenomenolgy conference were a part. In addition, it includes the list of talks from our website which comprise the online proceedings. The KITP no longer publishes conferences proceedings but rather makes recordings and visuals of all talks available on its website at www.kitp.ucsb.edu Program talks are available at http://online.kitp.ucsb.edu/online/strings06/ Conference talks are are at http://online.itp.ucsb.edu/online/strings_c06/ and LHC Olympics talks are at http://online.itp.ucsb.edu/online/lhco_c06/. These talks constitute the proceedings of these meetings.

David Gross

2006-10-01T23:59:59.000Z

230

On Relation between String Theory and Multidimensional Cosmology  

E-Print Network [OSTI]

It is shown that a transition from a multidimensional cosmological model with one internal space of the dimension d_1 to the effective tree-level bosonic string corresponds to an infinite number of the internal dimensions: d_1 -> infinity.

A. Zhuk

1996-11-05T23:59:59.000Z

231

Order preserving vibrating strings and applications to Electrodynamics and  

E-Print Network [OSTI]

time. It has been advertised as a possible model for dark energy [GKMP]. From a mathematical point specifically to its shallow water version. Then, each vibrating string can be interpreted as a magnetic line

Brenier, Yann

232

Lovelock black holes in a string cloud background  

E-Print Network [OSTI]

We present an exact static, spherically symmetric black hole solution to the third order Lovelock gravity with a string cloud background in seven dimensions for the special case when the second and third order Lovelock coefficients are related via $\\tilde{\\alpha}^2_2=3\\tilde{\\alpha}_3\\;(\\equiv\\alpha^2)$. Further, we examine thermodynamic properties of this black hole to obtain exact expressions for mass, temperature, entropy and also perform the thermodynamic stability analysis. We see that a string cloud background makes a profound influence on horizon structure, thermodynamic properties and the stability of black holes. Interestingly, the entropy of the black hole is unaffected due to a string cloud background. However, the critical solution for thermodynamic stability is being affected by a string cloud background.

Tae-Hun Lee; Dharmanand Baboolal; Sushant G. Ghosh

2014-09-12T23:59:59.000Z

233

Cloud of strings for radiating black holes in Lovelock gravity  

E-Print Network [OSTI]

We present exact spherically symmetric null dust solutions in the third order Lovelock gravity with a string cloud background in arbitrary $N$ dimensions,. This represents radiating black holes and generalizes the well known Vaidya solution to Lovelock gravity with a string cloud in the background. We also discuss the energy conditions and horizon structures, and explicitly bring out the effect of the string clouds on the horizon structure of black hole solutions for the higher dimensional general relativity and Einstein-Gauss-Bonnet theories. It turns out that the presence of the coupling constant of the Gauss-Bonnet terms and/or background string clouds completely changes the structure of the horizon and this may lead to a naked singularity. We recover known spherically symmetric radiating models as well as static black holes in the appropriate limits.

Sushant G. Ghosh; Sunil D. Maharaj

2014-09-28T23:59:59.000Z

234

String Gas Shells, their Dual Radiation and Hedgehog Signature Control  

E-Print Network [OSTI]

We search for spherically symmetric, stationary solutions with a string gas shell as a source. The requirement of a uniform newtonian potential, or constancy of the 00 component of the metric, implies the existence of a "dual" radiation, which we argue can be interpreted as representing the virtual quantum fluctuations that stabilize the shell. A string hedgehog can be introduced also into the solution. For zero or small hedgehog strength the string gas shell is of a regular nature, while the dual radiation is of a spacelike nature. For higher hedgehog strengths however the radiation "materializes" and becomes timelike while the string gas shell becomes space like. The significance of these solutions for the quantum theory is discussed.

E. I. Guendelman

2009-03-12T23:59:59.000Z

235

Kolmogorov Complexity, String Information, Panspermia and the Fermi Paradox  

E-Print Network [OSTI]

Bit strings rather than byte files can be a mode of transmission both for intelligent signals and for travels of extraterrestrial life. Kolmogorov complexity, i.e. the minimal length of a binary coded string completely defining a system, can then, due to its universality, become a key concept in the strategy of the search of extraterrestrials. Evaluating, for illustration, the Kolmogorov complexity of the human genome, one comes to an unexpected conclusion that a low complexity compressed string - analog of Noah's ark - will enable the recovery of the totality of terrestrial life. The recognition of bit strings of various complexity up to incompressible Martin-L\\"{o}f random sequences, will require a different strategy for the analysis of the cosmic signals. The Fermi paradox "Where is Everybody?" can be viewed under in the light of such information panspermia, i.e. a Universe full of traveling life streams.

V. G. Gurzadyan

2005-09-26T23:59:59.000Z

236

Peakons, Strings, and the Finite Toda Lattice RICHARD BEALS  

E-Print Network [OSTI]

Peakons, Strings, and the Finite Toda Lattice RICHARD BEALS Yale University DAVID H. SATTINGER Utah;92 R. BEALS, D. H. SATTINGER, AND J. SZMIGIELSKI viewpoints was explored in an unpublished paper by Mc

Zakharov, Vladimir

237

Quantum hair and the string-black hole correspondence  

E-Print Network [OSTI]

We consider a thought experiment in which an energetic massless string probes a "stringhole" (a heavy string lying on the correspondence curve between strings and black holes) at large enough impact parameter for the regime to be under theoretical control. The corresponding, explicitly unitary, $S$-matrix turns out to be perturbatively sensitive to the microstate of the stringhole: in particular, at leading order in $l_s/b$, it depends on a projection of the stringhole's Lorentz-contracted quadrupole moment. The string-black hole correspondence is therefore violated if one assumes quantum hair to be exponentially suppressed as a function of black-hole entropy. Implications for the information paradox are briefly discussed.

Gabriele Veneziano

2013-03-28T23:59:59.000Z

238

Nonstatic global string in Brans-Dicke theory  

E-Print Network [OSTI]

Gravitational field of a nonstatic global string has been studied in the context of Brans-Dicke theory of gravity. Both the metric components and the BD scalar field are assumed to be nonseparable functions of time and space.The spacetime may or may not have any singularity at a finite distance from the string core but the singularity at a particular time always remains. It has been shown that the spacetime exhibits both outgoing and incoming gravitational radiation.

A. A. Sen; N. Banerjee

2000-07-19T23:59:59.000Z

239

A New Method for Finding Vacua in String Phenomenology  

E-Print Network [OSTI]

One of the central problems of string-phenomenology is to find stable vacua in the four dimensional effective theories which result from compactification. We present an algorithmic method to find all of the vacua of any given string-phenomenological system in a huge class. In particular, this paper reviews and then extends hep-th/0606122 to include various non-perturbative effects. These include gaugino condensation and instantonic contributions to the superpotential.

James Gray; Yang-Hui He; Anton Ilderton; Andre Lukas

2007-05-24T23:59:59.000Z

240

Gravitational field of a stationary circular cosmic string loop  

E-Print Network [OSTI]

Gravitational field of a stationary circular cosmic string loop has been studied in the context of full nonlinear Einstein's theory of gravity. It has been assumed that the radial and tangential stresses of the loop are equal to the energy density of the string loop. An exact solution for the system has been presented which has a singularity at a finite distance from the axis,but is regular for any other distances from the axis of the loop.

A; A. Sen; N. Banerjee

1998-06-22T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Superconducting cosmic string in Brans-Dicke theory  

E-Print Network [OSTI]

In the present work, the gravitational field of superconducting cosmic string has been investigated in the context of Brans-Dicke theory of gravity. We have presented two kind of solutions for the spacetime in the far field zone of the string. When the B-D scalar field is switched off, one of the solutions reduces to the solution earlier obtained by Moss and Poletti in General Relativity.

A. A. Sen

1999-05-25T23:59:59.000Z

242

Backdraft: String Creation in an Old Schwarzschild Black Hole  

E-Print Network [OSTI]

We analyze string production in the background of a Schwarzschild black hole, after developing first quantized methods which capture string-theoretic nonadiabatic effects which can exceed naive extrapolations of effective field theory. Late-time infalling observers are strongly boosted in the near horizon region relative to early observers and formation matter. In the presence of large boosts in flat spacetime, known string and D-brane scattering processes exhibit enhanced string production, even for large impact parameter. This suggests the possibility that the nonadiabatic dynamics required to realize the firewall proposal of AMPS occurs for old black holes, with the late-time observer catalyzing the effect. After setting up this dynamical thought experiment, we focus on a specific case: the production of open strings stretched D-particles, at least one of which falls in late (playing the role of a late time observer). For relatively boosted D-branes, we precisely recover earlier results of Bachas, McAllister and Mitra which we generalize to brane trajectories in the black hole geometry. For two classes of late-time probes, we find a regime of significant non-adiabaticity by horizon crossing, assessing its dependence on the boost in each case. Closed string probes, as well as additional effects in D-brane scattering, may produce other significant non-adiabatic effects depending on the boost, something we leave for further work.

Eva Silverstein

2014-02-21T23:59:59.000Z

243

Hanford Site Shares Lessons Learned in Retrieving Highly Radioactive...  

Energy Savers [EERE]

January 29, 2014 - 12:00pm Addthis A team from the Oak Ridge Office of Environmental Management observes equipment that will be used to retrieve highly radioactive sludge at the...

244

Computational imaging for 3D phase and coherence retrieval |...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Computational imaging for 3D phase and coherence retrieval Wednesday, December 10, 2014 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Laura Waller (UC Berkeley) Program...

245

Automatically Building a Stopword List for an Information Retrieval System  

E-Print Network [OSTI]

Lo,T.W.R. He,B. Ounis,I. Journal of Digital Information Management: special issue on the 5th Dutch-Belgian Information Retrieval Workshop (DIR'05).

Lo, T.W.R.; He, B.; Ounis, I.

246

ARM: Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals

Cadeddu, Maria

247

SNF fuel retrieval sub project safety analysis document  

SciTech Connect (OSTI)

This safety analysis is for the SNF Fuel Retrieval (FRS) Sub Project. The FRS equipment will be added to K West and K East Basins to facilitate retrieval, cleaning and repackaging the spent nuclear fuel into Multi-Canister Overpack baskets. The document includes a hazard evaluation, identifies bounding accidents, documents analyses of the accidents and establishes safety class or safety significant equipment to mitigate accidents as needed.

BERGMANN, D.W.

1999-02-24T23:59:59.000Z

248

Final Report String Phenomenology 2011: The Tenth Annual Meeting on String Phenomenology  

SciTech Connect (OSTI)

The Tenth Annual International String Phenomenology Conference was held at the University of Wisconsin, Madison on August 22-26, 2011. The Conference was organized by Profs. Gary Shiu and Lisa Everett, with the help of two postdoctoral fellows Heng-Yu Chen and Jiajun Xu. The scientific subjects of the talks and discussions were chosen to be widely interdisciplinary, reflecting the scope and maturity of the field. The conference brought together researchers of diverse subfields in physics and mathematics to present and discuss recent developments in connecting observable particle physics and cosmology with the domain of fundamental theory. This report summarizes the outcome of this conference.

Shiu, Gary; Everett, Lisa

2011-08-26T23:59:59.000Z

249

From Strings to the LHC. Les Houches Lectures on String Phenomenology  

E-Print Network [OSTI]

These notes are based on lectures given at the Les Houches Summer School in 2011, which was centered on the general topic "Theoretical Physics to face the challenge of LHC". In these lectures I reviewed a number of topics in the field of String Phenomenology, focusing on orientifold/F-theory models yielding semi-realistic low-energy physics. The emphasis was on the extraction of the low-energy effective action and the possible test of specific models at LHC. These notes are a brief summary, appropriately updated, of some of the main topics covered in the lectures.

Luis E. Ibanez

2012-04-24T23:59:59.000Z

250

Cloud Property Retrieval Products for Graciosa Island, Azores  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The motivation for developing this product was to use the Dong et al. 1998 method to retrieve cloud microphysical properties, such as cloud droplet effective radius, cloud droplets number concentration, and optical thickness. These retrieved properties have been used to validate the satellite retrieval, and evaluate the climate simulations and reanalyses. We had been using this method to retrieve cloud microphysical properties over ARM SGP and NSA sites. We also modified the method for the AMF at Shouxian, China and some IOPs, e.g. ARM IOP at SGP in March, 2000. The ARSCL data from ARM data archive over the SGP and NSA have been used to determine the cloud boundary and cloud phase. For these ARM permanent sites, the ARSCL data was developed based on MMCR measurements, however, there were no data available at the Azores field campaign. We followed the steps to generate this derived product and also include the MPLCMASK cloud retrievals to determine the most accurate cloud boundaries, including the thin cirrus clouds that WACR may under-detect. We use these as input to retrieve the cloud microphysical properties. Due to the different temporal resolutions of the derived cloud boundary heights product and the cloud properties product, we submit them as two separate netcdf files.

Dong, Xiquan

251

Hanford contact-handled transuranic drum retrieval project planning document  

SciTech Connect (OSTI)

The Hanford Site is one of several US Department of Energy (DOE) sites throughout the US that has generated and stored transuranic (TRU) wastes. The wastes were primarily placed in 55-gallon drums, stacked in trenches, and covered with soil. In 1970, the Nuclear Regulatory Commission ordered that TRU wastes be segregated from other radioactive wastes and placed in retrievable storage until such time that the waste could be sent to a geologic repository and permanently disposed. Retrievable storage also defined container storage life by specifying that a container must be retrievable as a contamination-free container for 20 years. Hanford stored approximately 37,400 TRU containers in 20-year retrievable storage from 1970 to 1988. The Hanford TRU wastes placed in 20-year retrievable storage are considered disposed under existing Resource Conservation and Recovery Act (RCRA) regulations since they were placed in storage prior to September 1988. The majority of containers were 55-gallon drums, but 20-year retrievable storage includes several TRU wastes covered with soil in different storage methods.

DEMITER, J.A.

1998-11-17T23:59:59.000Z

252

Cloud Property Retrieval Products for Graciosa Island, Azores  

SciTech Connect (OSTI)

The motivation for developing this product was to use the Dong et al. 1998 method to retrieve cloud microphysical properties, such as cloud droplet effective radius, cloud droplets number concentration, and optical thickness. These retrieved properties have been used to validate the satellite retrieval, and evaluate the climate simulations and reanalyses. We had been using this method to retrieve cloud microphysical properties over ARM SGP and NSA sites. We also modified the method for the AMF at Shouxian, China and some IOPs, e.g. ARM IOP at SGP in March, 2000. The ARSCL data from ARM data archive over the SGP and NSA have been used to determine the cloud boundary and cloud phase. For these ARM permanent sites, the ARSCL data was developed based on MMCR measurements, however, there were no data available at the Azores field campaign. We followed the steps to generate this derived product and also include the MPLCMASK cloud retrievals to determine the most accurate cloud boundaries, including the thin cirrus clouds that WACR may under-detect. We use these as input to retrieve the cloud microphysical properties. Due to the different temporal resolutions of the derived cloud boundary heights product and the cloud properties product, we submit them as two separate netcdf files.

Dong, Xiquan

2014-05-05T23:59:59.000Z

253

What is the maximum rate at which entropy of a string can increase?  

SciTech Connect (OSTI)

According to Susskind, a string falling toward a black hole spreads exponentially over the stretched horizon due to repulsive interactions of the string bits. In this paper such a string is modeled as a self-avoiding walk and the string entropy is found. It is shown that the rate at which information/entropy contained in the string spreads is the maximum rate allowed by quantum theory. The maximum rate at which the black hole entropy can increase when a string falls into a black hole is also discussed.

Ropotenko, Kostyantyn [State Administration of Communications, Ministry of Transport and Communications of Ukraine 22, Khreschatyk, 01001, Kyiv (Ukraine)

2009-03-15T23:59:59.000Z

254

Mescalero Apache Tribe Monitored Retrievable Storage (MRS)  

SciTech Connect (OSTI)

The Nuclear Waste Policy Act of 1982, as amended, authorizes the siting, construction and operation of a Monitored Retrievable Storage (MRS) facility. The MRS is intended to be used for the temporary storage of spent nuclear fuel from the nation's nuclear power plants beginning as early as 1998. Pursuant to the Nuclear Waste Policy Act, the Office of the Nuclear Waste Negotiator was created. On October 7, 1991, the Nuclear Waste Negotiator invited the governors of states and the Presidents of Indian tribes to apply for government grants in order to conduct a study to assess under what conditions, if any, they might consider hosting an MRS facility. Pursuant to this invitation, on October 11, 1991 the Mescalero Apache Indian Tribe of Mescalero, NM applied for a grant to conduct a phased, preliminary study of the safety, technical, political, environmental, social and economic feasibility of hosting an MRS. The preliminary study included: (1) An investigative education process to facilitate the Tribe's comprehensive understanding of the safety, environmental, technical, social, political, and economic aspects of hosting an MRS, and; (2) The development of an extensive program that is enabling the Tribe, in collaboration with the Negotiator, to reach an informed and carefully researched decision regarding the conditions, (if any), under which further pursuit of the MRS would be considered. The Phase 1 grant application enabled the Tribe to begin the initial activities necessary to determine whether further consideration is warranted for hosting the MRS facility. The Tribe intends to pursue continued study of the MRS in order to meet the following objectives: (1) Continuing the education process towards a comprehensive understanding of the safety, environmental, technical, social and economic aspects of the MRS; (2) Conducting an effective public participation and information program; (3) Participating in MRS meetings.

Peso, F.

1992-03-13T23:59:59.000Z

255

{sup 103}Pd strings: Monte Carlo assessment of a new approach to brachytherapy source design  

SciTech Connect (OSTI)

Purpose: A new type of{sup 103}Pd source (CivaString and CivaThin by CivaTech Oncology, Inc.) is examined. The source contains {sup 103}Pd and Au radio-opaque marker(s), all contained within low-Z{sub eff} organic polymers that permit source flexibility. The CivaString source is available in lengths L of 10, 20, 30, 40, 50, and 60 mm, and referred to in the current study as CS10–CS60, respectively. A thinner design, CivaThin, has sources designated as CT10–CT60, respectively. The CivaString and CivaThin sources are 0.85 and 0.60 mm in diameter, respectively. The source design is novel and offers an opportunity to examine its interesting dosimetric properties in comparison to conventional {sup 103}Pd seeds. Methods: The MCNP5 radiation transport code was used to estimate air-kerma rate and dose rate distributions with polar and cylindrical coordinate systems. Doses in water and prostate tissue phantoms were compared to determine differences between the TG-43 formalism and realistic clinical circumstances. The influence of Ti encapsulation and 2.7 keV photons was examined. The accuracy of superposition of dose distributions from shorter sources to create longer source dose distributions was also assessed. Results: The normalized air-kerma rate was not highly dependent onL or the polar angle ?, with results being nearly identical between the CivaString and CivaThin sources for common L. The air-kerma strength was also weakly dependent on L. The uncertainty analysis established a standard uncertainty of 1.3% for the dose-rate constant ?, where the largest contributors were ?{sub en}/? and ?/?. The ? values decreased with increasing L, which was largely explained by differences in solid angle. The radial dose function did not substantially vary among the CivaString and CivaThin sources for r ? 1 cm. However, behavior for r < 1 cm indicated that the Au marker(s) shielded radiation for the sources having L = 10, 30, and 50 mm. The 2D anisotropy function exhibited peaks and valleys that corresponded to positions adjacent to {sup 103}Pd wells and Au markers, respectively. Dose distributions of both source types had minimal anisotropy in comparison to conventional {sup 103}Pd seeds. Contributions by 2.7 keV photons comprised ?0.1% of the dose from all photons at positions farther than 0.13 mm from the polymer source surface. Differences between absorbed dose to water and prostate became more substantial as distance from the sources increased, with prostate dose being about 13% lower for r = 5 cm. Using a cylindrical coordinate system, dose superposition of small length sources to replicate the dose distribution for a long length source proved to be a robust technique; a 2.0% tolerance compared with the reference dose distribution did not exceed 0.1 cm{sup 3} for any of the examined source combinations. Conclusions: By design, the CivaString and CivaThin sources have novel dosimetric characteristics in comparison to Ti-encapsulated{sup 103}Pd seeds. The dosimetric characterization has determined the reasons for these differences through analysis using Monte Carlo-based radiation transport simulations.

Rivard, Mark J., E-mail: mark.j.rivard@gmail.com [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States); Reed, Joshua L.; DeWerd, Larry A. [Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States)] [Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States)

2014-01-15T23:59:59.000Z

256

Fully Anisotropic String Cosmologies, Maxwell Fields and Primordial Shear  

E-Print Network [OSTI]

We present a class of exact cosmological solutions of the low energy string effective action in the presence of a homogeneous magnetic fields. We discuss the physical properties of the obtained (fully anisotropic) cosmologies paying particular attention to their vacuum limit and to the possible isotropization mechanisms. We argue that quadratic curvature corrections are able to isotropize fully anisotropic solutions whose scale factors describe accelerated expansion. Moreover, the degree of isotropization grows with the duration of the string phase. We follow the fate of the shear parameter in a decelerated phase where, dilaton, magnetic fields and radiation fluid are simultaneously present. In the absence of any magnetic field a long string phase immediately followed by radiation is able to erase large anisotropies. Conversely, if a short string phase is followed by a long dilaton dominated phase the anisotropies can be present, in principle, also at later times. The presence of magnetic seeds after the end of the string phase can induce further anisotropies which can be studied within the formalism reported in this paper.

Massimo Giovannini

1998-12-07T23:59:59.000Z

257

Hanford Tanks Initiative fiscal year 1997 retrieval technology demonstrations  

SciTech Connect (OSTI)

The Hanford Tanks Initiative was established in 1996 to address a range of retrieval and closure issues associated with radioactive and hazardous waste stored in Hanford`s single shell tanks (SSTs). One of HTI`s retrieval goals is to ``Successfully demonstrate technology(s) that provide expanded capabilities beyond past practice sluicing and are extensible to retrieve waste from other SSTS.`` Specifically, HTI is to address ``Alternative technologies to past practice sluicing`` ... that can ... ``successfully remove the hard heel from a sluiced tank or to remove waste from a leaking SST`` (HTI Mission Analysis). During fiscal year 1997, the project contracted with seven commercial vendor teams to demonstrate retrieval technologies using waste simulants. These tests were conducted in two series: three integrated tests (IT) were completed in January 1997, and four more comprehensive Alternative Technology Retrieval Demonstrations (ARTD) were completed in July 1997. The goal of this testing was to address issues to minimize the risk, uncertainties, and ultimately the overall cost of removing waste from the SSTS. Retrieval technologies can be separated into three tracks based on how the tools would be deployed in the tank: globally (e.g., sluicing) or using vehicles or robotic manipulators. Accordingly, the HTI tests included an advanced sluicer (Track 1: global systems), two different vehicles (Track 2: vehicle based systems), and three unique manipulators (Track 3: arm-based systems), each deploying a wide range of dislodging tools and conveyance systems. Each industry team produced a system description as envisioned for actual retrieval and a list of issues that could prevent using the described system; defined the tests to resolve the issues; performed the test; and reported the results, lessons learned, and state of issue resolution. These test reports are cited in this document, listed in the reference section, and summarized in the appendices. This report analyzes the retrieval testing issues and describes what has been learned and issues that need further resolution. As such, it can serve as a guide to additional testing that must be performed before the systems are used in-tank. The major issues discussed are tank access, deployment, mining strategy, waste retrieval, liquid scavenging (liquid usage), maneuverability, positioning, static and dynamic performance, remote operations, reliability, availability, maintenance, tank safety, and cost.

Berglin, E.J.

1998-02-05T23:59:59.000Z

258

V-075: EMC AlphaStor Command Injection and Format String Flaws...  

Broader source: Energy.gov (indexed) [DOE]

5: EMC AlphaStor Command Injection and Format String Flaws Let Remote Users Execute Arbitrary Code V-075: EMC AlphaStor Command Injection and Format String Flaws Let Remote Users...

259

SLUDGE RETRIEVAL FROM HANFORD K WEST BASIN SETTLER TANKS  

SciTech Connect (OSTI)

In 2010, an innovative, remotely operated retrieval system was deployed to successfully retrieve over 99.7% of the radioactive sludge from ten submerged tanks in Hanford's K-West Basin. As part of K-West Basin cleanup, the accumulated sludge needed to be removed from the 0.5 meter diameter by 5 meter long settler tanks and transferred approximately 45 meters to an underwater container for sampling and waste treatment. The abrasive, dense, non-homogeneous sludge was the product of the washing process of corroded nuclear fuel. It consists of small (less than 600 micron) particles of uranium metal, uranium oxide, and various other constituents, potentially agglomerated or cohesive after 10 years of storage. The Settler Tank Retrieval System (STRS) was developed to access, mobilize and pump out the sludge from each tank using a standardized process of retrieval head insertion, periodic high pressure water spray, retraction, and continuous pumping of the sludge. Blind operations were guided by monitoring flow rate, radiation levels in the sludge stream, and solids concentration. The technology developed and employed in the STRS can potentially be adapted to similar problematic waste tanks or pipes that must be remotely accessed to achieve mobilization and retrieval of the sludge within.

ERPENBECK EG; LESHIKAR GA

2011-01-13T23:59:59.000Z

260

Wilson lines for AdS_5 black strings  

E-Print Network [OSTI]

We describe a simple method of extending AdS_5 black string solutions of 5d gauged supergravity in a supersymmetric way by addition of Wilson lines along a circular direction in space. When this direction is chosen along the string, and due to the specific form of 5d supergravity that features Chern-Simons terms, the existence of magnetic charges automatically generates conserved electric charges in a 5d analogue of the Witten effect. Therefore we find a rather generic, model-independent way of adding electric charges to already existing solutions with no backreaction from the geometry or breaking of any symmetry. We use this method to explicitly write down more general versions of the Benini-Bobev black strings and comment on the implications for the dual field theory and the similarities with generalizations of the Cacciatori-Klemm black holes in AdS_4.

Kiril Hristov; Stefanos Katmadas

2014-12-03T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Possible influence of the two string events on the hadron formation in a nuclear environment  

E-Print Network [OSTI]

One of the basic assumptions of the string model is that as a result of a DIS in nucleus a single string arises, which then breaks into hadrons. However the pomeron exchange considered in this work, leads to the production of two strings in the one event. The hadrons produced in these events have smaller formation lengths, than those with the same energy produced in the single string events. As a consequence, they undergo more substantial absorption in the nuclear matter.

N. Akopov; L. Grigoryan; Z. Akopov

2007-05-07T23:59:59.000Z

262

Possible influence of the two string events on the hadron formation in a nuclear environment  

E-Print Network [OSTI]

One of the basic assumptions of the string model is that as a result of a DIS in nucleus a single string arises, which then breaks into hadrons. However the pomeron exchange considered in this work, leads to the production of two strings in the one event. The hadrons produced in these events have smaller formation lengths, than those with the same energy produced in the single string events. As a consequence, they undergo more substantial absorption in the nuclear matter.

Akopov, N; Akopov, Z

2007-01-01T23:59:59.000Z

263

Theoretical Research in Cosmology, High-Energy Physics and String Theory  

SciTech Connect (OSTI)

The research was in the area of Theoretical Physics: Cosmology, High-Energy Physics and String Theory

Ng, Y Jack; Dolan, Louise; Mersini-Houghton, Laura; Frampton, Paul

2013-07-29T23:59:59.000Z

264

THE RETRIEVAL KNOWLEDGE CENTER EVALUATION OF LOW TANK LEVEL MIXING TECHNOLOGIES FOR DOE HIGH LEVEL WASTE TANK RETRIEVAL 10516  

SciTech Connect (OSTI)

The Department of Energy (DOE) Complex has over two-hundred underground storage tanks containing over 80-million gallons of legacy waste from the production of nuclear weapons. The majority of the waste is located at four major sites across the nation and is planned for treatment over a period of almost forty years. The DOE Office of Technology Innovation & Development within the Office of Environmental Management (DOE-EM) sponsors technology research and development programs to support processing advancements and technology maturation designed to improve the costs and schedule for disposal of the waste and closure of the tanks. Within the waste processing focus area are numerous technical initiatives which included the development of a suite of waste removal technologies to address the need for proven equipment and techniques to remove high level radioactive wastes from the waste tanks that are now over fifty years old. In an effort to enhance the efficiency of waste retrieval operations, the DOE-EM Office of Technology Innovation & Development funded an effort to improve communications and information sharing between the DOE's major waste tank locations as it relates to retrieval. The task, dubbed the Retrieval Knowledge Center (RKC) was co-lead by the Savannah River National Laboratory (SRNL) and the Pacific Northwest National Laboratory (PNNL) with core team members representing the Oak Ridge and Idaho sites, as well as, site contractors responsible for waste tank operations. One of the greatest challenges to the processing and closure of many of the tanks is complete removal of all tank contents. Sizeable challenges exist for retrieving waste from High Level Waste (HLW) tanks; with complications that are not normally found with tank retrieval in commercial applications. Technologies currently in use for waste retrieval are generally adequate for bulk removal; however, removal of tank heels, the materials settled in the bottom of the tank, using the same technology have proven to be difficult. Through the RKC, DOE-EM funded an evaluation of adaptable commercial technologies that could assist with the removal of the tank heels. This paper will discuss the efforts and results of developing the RKC to improve communications and discussion of tank waste retrieval through a series of meetings designed to identify technical gaps in retrieval technologies at the DOE Hanford and Savannah River Sites. This paper will also describe the results of an evaluation of commercially available technologies for low level mixing as they might apply to HLW tank heel retrievals.

Fellinger, A.

2009-12-08T23:59:59.000Z

265

A classical instability for black strings and p-branes  

SciTech Connect (OSTI)

We investigate the evolution of small perturbations around black of strings and branes which are low energy solutions of string theory. For simplicity we focus attention on the zero charge case and show that there are unstable modes for a range of time frequency and wavelength in the extra 10 - D dimensions. These perturbations can be stabilized if the extra dimensions are compactified to a scale smaller than the minimum wavelength for which instability occurs and thus will not affect large astrophysical black holes in four dimensions. We comment on the implications of this result for the Cosmic Censorship Hypothesis

Gregory, R. (Chicago Univ., IL (United States). Enrico Fermi Inst.); Laflamme, R. (Los Alamos National Lab., NM (United States))

1993-01-01T23:59:59.000Z

266

A classical instability for black strings and p-branes  

SciTech Connect (OSTI)

We investigate the evolution of small perturbations around black of strings and branes which are low energy solutions of string theory. For simplicity we focus attention on the zero charge case and show that there are unstable modes for a range of time frequency and wavelength in the extra 10 - D dimensions. These perturbations can be stabilized if the extra dimensions are compactified to a scale smaller than the minimum wavelength for which instability occurs and thus will not affect large astrophysical black holes in four dimensions. We comment on the implications of this result for the Cosmic Censorship Hypothesis

Gregory, R. [Chicago Univ., IL (United States). Enrico Fermi Inst.; Laflamme, R. [Los Alamos National Lab., NM (United States)

1993-06-01T23:59:59.000Z

267

Anisotropic massive strings in scalar-tensor theory of gravitation  

E-Print Network [OSTI]

We present the model of anisotropic universe with string fluid as source of matter within the framework of scalar-tensor theory of gravitation. Exact solution of field equations are obtained by applying Berman's law of variation of Hubble's parameter which yields a constant value of DP. The nature of classical potential is examined for the model under consideration. It has been also found that the massive strings dominate in early universe and at long last disappear from universe. This is in agreement with current astronomical observations. The physical and dynamical properties of model are also discussed.

Anil Kumar Yadav

2012-11-15T23:59:59.000Z

268

A Simple Introduction to Grobner Basis Methods in String Phenomenology  

E-Print Network [OSTI]

In this talk I give an elementary introduction to the key algorithm used in recent applications of computational algebraic geometry to the subject of string phenomenology. I begin with a simple description of the algorithm itself and then give 3 examples of its use in physics. I describe how it can be used to obtain constraints on flux parameters, how it can simplify the equations describing vacua in 4d string models and lastly how it can be used to compute the vacuum space of the electroweak sector of the MSSM.

James Gray

2009-01-12T23:59:59.000Z

269

Hawking temperature of rotating charged black strings from tunneling  

SciTech Connect (OSTI)

Thermal radiations from spherically symmetric black holes have been studied from the point of view of quantum tunneling. In this paper we extend this approach to study radiation of fermions from charged and rotating black strings. Using WKB approximation and Hamilton-Jacobi method we work out the tunneling probabilities of incoming and outgoing fermions and find the correct Hawking temperature for these objects. We show that in appropriate limits the results reduce to those for the uncharged and non-rotating black strings.

Ahmed, Jamil; Saifullah, K., E-mail: jamil_051@yahoo.com, E-mail: saifullah@qau.edu.pk [Department of Mathematics, Quaid-i-Azam University, Islamabad (Pakistan)

2011-11-01T23:59:59.000Z

270

Black holes and black strings in plane waves  

E-Print Network [OSTI]

We investigate the construction of black holes and black strings in vacuum plane wave spacetimes using the method of matched asymptotic expansions. We find solutions of the linearised equations of motion in the asymptotic region for a general source on a plane wave background. We observe that these solutions do not satisfy our previously defined conditions for being asymptotically plane wave. Hence, the space of asymptotically plane wave solutions is restricted. We consider the solution in the near region, treating the plane wave as a perturbation of a black object, and find that there is a regular black string solution but no regular black hole solution.

Julian Le Witt; Simon F. Ross

2009-10-30T23:59:59.000Z

271

Investigation of single unit flashovers in HVDC insulator strings  

SciTech Connect (OSTI)

In HVDC transmission lines, a special phenomenon, so called single unit flashover, is observed under some special conditions. Only one or two insulator units repeat flashovers, not resulting in an overall flashover along the string. However, higher magnitudes of audible noise, radio and television interferences, may give a serious problem. Based on the investigation on {+-}500-kV full scale insulator strings, higher occurrence probability of single unit flashovers under cold-wet-switch-on conditions was clarified compared with normal continuous operating voltage conditions. Effectiveness of the newly proposed countermeasures to prevent single unit flashovers was demonstrated by experiments in laboratory and in field.

Ishikawa, Kouichi; Kageyama, Hiroshi; Yamada, Yasuhiro [Kansai Electric Power Co., Inc., Osaka (Japan)] [Kansai Electric Power Co., Inc., Osaka (Japan); Matsuoka, Ryosuke; Ito, Susumu; Sakanishi, Kenji [NGK Insulators, Ltd., Nagoya (Japan)] [NGK Insulators, Ltd., Nagoya (Japan)

1996-10-01T23:59:59.000Z

272

Physical Interpretation of the 26 Dimensions of Bosonic String Theory  

E-Print Network [OSTI]

The 26 dimensions of Closed Unoriented Bosonic String Theory are interpreted as the 26 dimensions of the traceless Jordan algebra J3(O)o of 3x3 Octonionic matrices, with each of the 3 Octonionic dimenisons of J3(O)o having the following physical interpretation: 4-dimensional physical spacetime plus 4-dimensional internal symmetry space; 8 first-generation fermion particles; 8 first-generation fermion anti-particles. This interpretation is consistent with interpreting the strings as World Lines of the Worlds of Many-Worlds Quantum Theory and the 26 dimensions as the degrees of freedom of the Worlds of the Many-Worlds.

Frank D. Smith Jr

2002-07-15T23:59:59.000Z

273

Quantum Private Information Retrieval has linear communication complexity  

E-Print Network [OSTI]

In Private Information Retrieval (PIR), a client queries an n-bit database in order to retrieve an entry of her choice, while maintaining privacy of her query value. Chor, Goldreich, Kushilevitz, and Sudan showed that, in the information-theoretical setting, a linear amount of communication is required for classical PIR protocols (and thus that the trivial protocol is optimal). This linear lower bound was shown by Nayak to hold also in the quantum setting. Here, we extend Nayak's result by considering approximate privacy, and requiring security only against "specious" adversaries, which are, in analogy to classical honest-but-curious adversaries, the weakest reasonable quantum adversaries. We show that, even in this weakened scenario, Quantum Private Information Retrieval (QPIR) requires n qubits of communication. From this follows that Le Gall's recent QPIR protocol with sublinear communication complexity is not information-theoretically private, against the weakest reasonable cryptographic adversary.

Ämin Baumeler; Anne Broadbent

2014-01-29T23:59:59.000Z

274

Hybrid MSW + VO Solution of the Solar Neutrino Problem in String-Motivated Unified Theories  

E-Print Network [OSTI]

It is shown that the hybrid MSW + VO solution of the solar neutrino problem, according to which the solar nu_e undergo matter-enhanced transitions into nu_mu, nu_tau in the Sun followed by long wave length (about 1.5 10^8 km) nu_e -> nu_mu, nu_tau oscillations in vacuum between the Sun and the Earth, can occur naturally in string-motivated grand unified theories. We consider the supersymmetric version of a string-type SU(4)xSU(2)_LxSU(2)_R theory with U(1)_X family symmetry, which was shown to successfully describe the charged fermion masses and the quark mixing, and extend the earlier fermion mass analysis to the neutrino sector. We show that the four oscillation parameters Delta m_31^2, Delta m_21^2 and sin^2 2 theta_12, sin^2 2 theta_13, characterising the combined matter-enhanced transitions and vacuum oscillations of the solar nu_e, naturally get values in the ranges of the hybrid MSW + VO solutions found recently.

B. C. Allanach; G. K. Leontaris; S. T. Petcov

1997-12-19T23:59:59.000Z

275

Cloud-Scale Vertical Velocity and Turbulent Dissipation Rate Retrievals  

SciTech Connect (OSTI)

Time-height fields of retrieved in-cloud vertical wind velocity and turbulent dissipation rate, both retrieved primarily from vertically-pointing, Ka-band cloud radar measurements. Files are available for manually-selected, stratiform, mixed-phase cloud cases observed at the North Slope of Alaska (NSA) site during periods covering the Mixed-Phase Arctic Cloud Experiment (MPACE, late September through early November 2004) and the Indirect and Semi-Direct Aerosol Campaign (ISDAC, April-early May 2008). These time periods will be expanded in a future submission.

Shupe, Matthew

2013-05-22T23:59:59.000Z

276

Cloud-Scale Vertical Velocity and Turbulent Dissipation Rate Retrievals  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Time-height fields of retrieved in-cloud vertical wind velocity and turbulent dissipation rate, both retrieved primarily from vertically-pointing, Ka-band cloud radar measurements. Files are available for manually-selected, stratiform, mixed-phase cloud cases observed at the North Slope of Alaska (NSA) site during periods covering the Mixed-Phase Arctic Cloud Experiment (MPACE, late September through early November 2004) and the Indirect and Semi-Direct Aerosol Campaign (ISDAC, April-early May 2008). These time periods will be expanded in a future submission.

Shupe, Matthew

277

Evaluating cloud retrieval algorithms with the ARM BBHRP framework  

SciTech Connect (OSTI)

Climate and weather prediction models require accurate calculations of vertical profiles of radiative heating. Although heating rate calculations cannot be directly validated due to the lack of corresponding observations, surface and top-of-atmosphere measurements can indirectly establish the quality of computed heating rates through validation of the calculated irradiances at the atmospheric boundaries. The ARM Broadband Heating Rate Profile (BBHRP) project, a collaboration of all the working groups in the program, was designed with these heating rate validations as a key objective. Given the large dependence of radiative heating rates on cloud properties, a critical component of BBHRP radiative closure analyses has been the evaluation of cloud microphysical retrieval algorithms. This evaluation is an important step in establishing the necessary confidence in the continuous profiles of computed radiative heating rates produced by BBHRP at the ARM Climate Research Facility (ACRF) sites that are needed for modeling studies. This poster details the continued effort to evaluate cloud property retrieval algorithms within the BBHRP framework, a key focus of the project this year. A requirement for the computation of accurate heating rate profiles is a robust cloud microphysical product that captures the occurrence, height, and phase of clouds above each ACRF site. Various approaches to retrieve the microphysical properties of liquid, ice, and mixed-phase clouds have been processed in BBHRP for the ACRF Southern Great Plains (SGP) and the North Slope of Alaska (NSA) sites. These retrieval methods span a range of assumptions concerning the parameterization of cloud location, particle density, size, shape, and involve different measurement sources. We will present the radiative closure results from several different retrieval approaches for the SGP site, including those from Microbase, the current 'reference' retrieval approach in BBHRP. At the NSA, mixed-phase clouds and cloud with a low optical depth are prevalent; the radiative closure studies using Microbase demonstrated significant residuals. As an alternative to Microbase at NSA, the Shupe-Turner cloud property retrieval algorithm, aimed at improving the partitioning of cloud phase and incorporating more constrained, conditional microphysics retrievals, also has been evaluated using the BBHRP data set.

Mlawer,E.; Dunn,M.; Mlawer, E.; Shippert, T.; Troyan, D.; Johnson, K. L.; Miller, M. A.; Delamere, J.; Turner, D. D.; Jensen, M. P.; Flynn, C.; Shupe, M.; Comstock, J.; Long, C. N.; Clough, S. T.; Sivaraman, C.; Khaiyer, M.; Xie, S.; Rutan, D.; Minnis, P.

2008-03-10T23:59:59.000Z

278

RandomString is a small web application, containing one java servlet. It allows users to enter a list of strings to be randomly chosen with two options: with replacement or without replacement (default).  

E-Print Network [OSTI]

a list of strings to be randomly chosen with two options: with replacement or without replacement of strings and choosing them randomly with two options: with replacement or without replacement (default strings are separated by carriage return. 2. User selects to randomly choose strings `without replacement

Offutt, Jeff

279

Finite Temperature Bosonic Closed Strings: Thermal Duality and the Kosterlitz Thouless Transition  

E-Print Network [OSTI]

We elucidate the properties of a gas of free closed bosonic strings in thermal equilibrium. Our starting point is the intensive generating functional of connected one-loop closed vacuum string graphs given by the Polyakov path integral. Invariance of the path integral under modular transformations gives a thermal duality invariant expression for the free energy of free closed strings at finite temperature. The free bosonic string gas exhibits a self-dual Kosterlitz-Thouless phase transition. The thermodynamic potentials of the gas of free bosonic closed strings are shown to exhibit an infinite hierarchy of thermal self-duality relations. Note Added (Sep 2005).

S. Chaudhuri

2005-09-12T23:59:59.000Z

280

Refined Chern-Simons Theory and Topological String  

E-Print Network [OSTI]

We show that refined Chern-Simons theory and large N duality can be used to study the refined topological string with and without branes. We derive the refined topological vertex of hep-th/0701156 and hep-th/0502061 from a link invariant of the refined SU(N) Chern-Simons theory on S^3, at infinite N. Quiver-like Chern-Simons theories, arising from Calabi-Yau manifolds with branes wrapped on several minimal S^3's, give a dual description of a large class of toric Calabi-Yau. We use this to derive the refined topological string amplitudes on a toric Calabi-Yau containing a shrinking P^2 surface. The result is suggestive of the refined topological vertex formalism for arbitrary toric Calabi-Yau manifolds in terms of a pair of vertices and a choice of a Morse flow on the toric graph, determining the vertex decomposition. The dependence on the flow is reminiscent of the approach to the refined topological string in upcoming work of Nekrasov and Okounkov. As a byproduct, we show that large N duality of the refined topological string explains the ``mirror symmetry`` of the refined colored HOMFLY invariants of knots.

Mina Aganagic; Shamil Shakirov

2012-10-09T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Renewal Strings for Cleaning Astronomical Databases Amos J. Storkey  

E-Print Network [OSTI]

Renewal Strings for Cleaning Astronomical Databases Amos J. Storkey School of Informatics 5 Forrest astronomical survey data. 1 INTRODUCTION Digital sky surveys in astronomy are a fundamental research resource- veys are carried out in all wavelength ranges, from high energy gamma rays to the longest wavelength ra

Storkey, Amos

282

Renewal Strings for Cleaning Astronomical Databases Amos J. Storkey #  

E-Print Network [OSTI]

Renewal Strings for Cleaning Astronomical Databases Amos J. Storkey # School of Informatics 5 astronomical survey data. 1 INTRODUCTION Digital sky surveys in astronomy are a fundamental research resource­ veys are carried out in all wavelength ranges, from high energy gamma rays to the longest wavelength ra

Storkey, Amos

283

Landau Quantization in the Spinning Cosmic String Spacetime  

E-Print Network [OSTI]

We analyze the quantum phenomenon arising from the interaction of a spinless charged particle with a rotating cosmic string, under the action of a static and uniform magnetic field parallel to the string. We calculate the energy levels of the particle in the non-relativistic approach, showing how these energies depend on the parameters involved in the problem. In order to do this, we solve the time independent Schroedinger equation in the geometry of the spinning cosmic string, taking into account that the coupling between the rotation of the spacetime and the angular momentum of the particle is very weak, such that makes sense to apply the Schr\\"odinger equation in a curved background whose metric has an off diagonal term which involves time and space. It is also assumed that the particle orbits sufficiently far from the boundary of the region of closed timelike curves which exist around this topological defect. Finally, we find the Landau levels of the particle in the presence of a spinning cosmic string endowed with internal structure, i.e., having finite width and uniformly filled with both material and vacuum energies.

Celio R. Muniz; Valdir B. Bezerra; Marcony S. Cunha

2014-03-26T23:59:59.000Z

284

Classification of Flipped SU(5) Heterotic-String Vacua  

E-Print Network [OSTI]

We extend the classification of the free fermionic heterotic-string vacua to models in which the SO(10) GUT symmetry at the string scale is broken to the flipped SU(5) subgroup. In our classification method, the set of basis vectors defined by the boundary conditions which are assigned to the free fermions is fixed and the enumeration of the string vacua is obtained in terms of the Generalised GSO (GGSO) projection coefficients entering the one-loop partition function. We derive algebraic expressions for the GGSO projections for all the physical states appearing in the sectors generated by the set of basis vectors. This enables the analysis of the entire string spectrum to be programmed in to a computer code therefore, we performed a statistical sampling in the space of 2^{44} (approximately 10^{13}) flipped $SU(5)$ vacua and scanned up to 10^{12} GGSO configurations. For that purpose, two independent codes were developed based on JAVA and FORTRAN95. All the results presented here are confirmed by the two independent routines. Contrary to the corresponding Pati-Salam classification, we do not find exophobic flipped SU(5) vacua with an odd number of generations. We study the structure of exotic states appearing in the three generation models that additionally contain a viable Higgs spectrum. Moreover, we demonstrate the existence of models in which all the exotic states are confined by a hidden sector non-Abelian gauge symmetry as well as models that may admit the racetrack mechanism.

Alon E. Faraggi; John Rizos; Hasan Sonmez

2014-03-31T23:59:59.000Z

285

Effective string theory description of the interface free energy  

E-Print Network [OSTI]

We compare the predictions of the Nambu-Goto effective string model with a set of high precision Monte Carlo results for interfaces with periodic boundary conditions in the 3D Ising model. We compute the free energy in the covariant gauge exactly, up to the inclusion of the Liouville mode. The perturbative expansion of this result agrees both with the result evaluated several years ago by Dietz and Filk in the physical gauge and with a recent calculation with the Polchinski-Strominger action. We also derive the effective string spectrum which, because of the different boundary conditions, is very different from the well known one of Arvis. Taking into proper account the effective string corrections and exploiting some technical improvements in the simulations we obtain precise estimate of the amplitude ratios T_c/\\sqrt{sigma}, m_{0++}/\\sqrt{\\sigma} and sigma xi_{2nd}^2. We also discuss the behaviour of the effective string free energy in the dimensional reduction limit (i.e., near the deconfinement transition of the dual 3d gauge Ising model) and its relationship with the 2d Ising model interfaces

M. Billo; M. Caselle; L. Ferro; M. Hasenbusch; M. Panero

2007-10-09T23:59:59.000Z

286

Combinatorial Problems on Strings with Applications to Protein Folding  

E-Print Network [OSTI]

Combinatorial Problems on Strings with Applications to Protein Folding Alantha Newman MIT San Jose, CA 95120, USA ruhl@almaden.ibm.com Abstract We consider the problem of protein folding in linear time. 1 Introduction We consider the problem of protein folding in the HP model on the three

Newman, Alantha

287

STRING LOOPS IN BACKGROUND FIELDS Scott Alan Yost  

E-Print Network [OSTI]

excellent collaborators. They have made my stay at Princeton very productive and enjoyable. I thank E. LiebSTRING LOOPS IN BACKGROUND FIELDS Scott Alan Yost A dissertation presented to the faculty formalism. ii #12;Acknowledgements I would like to thank my advisor, Chiara Nappi, for her support, advice

Yost, Scott

288

HBT puzzle at RHIC AMPT model with String Melting  

E-Print Network [OSTI]

/RsideSmall radii Small duration time dt by Stephen Johnson at RWW02 One way out: Hydro Softest point in EOS Measured extensively in heavy ion collisions reasonably described by models (hydro-ph/01120062 recent hydro studies: #12;HIJING energy in strings(soft) and minijet partons(hard) ZPC (Zhang

Lin, Zi-wei

289

Landscape statistics of the low autocorrelated binary string problem  

E-Print Network [OSTI]

Landscape statistics of the low autocorrelated binary string problem Fernando F. Ferreiraa , Jos, NM 87501, USA Abstract. The statistical properties of the energy landscape of the low autocorrelated disordered models. Using two global measures of landscape structure which have been introduced

Stadler, Peter F.

290

Landscape statistics of the low autocorrelated binary string problem  

E-Print Network [OSTI]

Landscape statistics of the low autocorrelated binary string problem Fernando F. Ferreira a , Jos, NM 87501, USA Abstract. The statistical properties of the energy landscape of the low autocorrelated disordered models. Using two global measures of landscape structure which have been introduced

Stadler, Peter F.

291

Coset-Space String Compactification Leading To 14 Subcritical Dimensions  

E-Print Network [OSTI]

Using sigma-model approach, we study a class of coset spaces with torsion which compactify the D=26 closed bose-string theory. Requiring also that massless chiral fermions arise from the geometry/topology of coset space, we are left with the unique possibility: it implies D=14 subcritical dimensions and the isometry group G_2 X G_2.

A. M. Gavrilik

2001-08-23T23:59:59.000Z

292

Tanks Focus Area retrieval process development and enhancements FY96 technology development summary report  

SciTech Connect (OSTI)

The Retrieval Process Development and Enhancements (RPD&E) activities are part of the Retrieval and Closure Program of the U.S. Department of Energy (DOE) EM-50 Tanks Focus Area. The purposes of RPD&E are to understand retrieval processes, including emerging and existing technologies, and to gather data on those processes, so that end users have the requisite technical basis to make retrieval decisions. Work has been initiated to support the need for multiple retrieval technologies across the DOE complex. Technologies addressed during FY96 focused on enhancements to sluicing, borehole mining, confined sluicing retrieval end effectors, the lightweight scarifier, and pulsed air mixing. Furthermore, a decision tool and database have been initiated to link retrieval processes with tank closure to assist end users in making retrieval decisions.

Rinker, M.W.; Bamberger, J.A.; Hatchell, B.K. [and others

1996-09-01T23:59:59.000Z

293

A Patent System Ontology for Facilitating Retrieval of Patent Related Information  

E-Print Network [OSTI]

A Patent System Ontology for Facilitating Retrieval of Patent Related Information Siddharth Taduri and consists of laws, regulations, patents, court litigations, scientific publications, and more. Although framework to facilitate retrieval of patents and related information across multiple diverse

Stanford University

294

IEEE TRANSACTIONS ON MULTIMEDIA 1 Scalable Face Image Retrieval using  

E-Print Network [OSTI]

the effectiveness of different attributes and vital factors essential for face retrieval. Experimenting on two University (e-mail: sirius42@cmlab.csie.ntu.edu.tw). Y.-Y. Chen is with the Department of Computer Science and Information Engineering, National Taiwan University (e-mail: yanying@cmlab.csie.ntu.edu.tw). Y.-H. Kuo

Hsu, Winston H.

295

TECHNOLOGY SUMMARY ADVANCING TANK WASTE RETRIEVAL AND PROCESSING  

SciTech Connect (OSTI)

This technology overview provides a high-level summary of technologies being investigated and developed by Washington River Protection Solutions (WRPS) to advance Hanford Site tank waste retrieval and processing. Technology solutions are outlined, along with processes and priorities for selecting and developing them.

SAMS TL; MENDOZA RE

2010-08-11T23:59:59.000Z

296

CRAD, Maintenance- Idaho Accelerated Retrieval Project Phase II  

Broader source: Energy.gov [DOE]

A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2006 Commencement of Operations assessment of the Maintenance program at the Idaho Accelerated Retrieval Project Phase II.

297

CRAD, Criticality Safety- Idaho Accelerated Retrieval Project Phase II  

Broader source: Energy.gov [DOE]

A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2006 Commencement of Operations assessment of the Criticality Safety program at the Idaho Accelerated Retrieval Project Phase II.

298

Intelligent Mobile Agents for Information Retrieval and Knowledge Discovery from  

E-Print Network [OSTI]

or software agents for intelligent, selective, and context­sensitive data gathering and data assimilation assimilation, and knowl­ edge discovery using heterogeneous, distributed data and knowledge sources. (See [1Intelligent Mobile Agents for Information Retrieval and Knowledge Discovery from Distributed Data

Honavar, Vasant

299

CRAD, Conduct of Operations- Idaho Accelerated Retrieval Project Phase II  

Broader source: Energy.gov [DOE]

A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February, 2006 Commencement of Operations assessment of the Conduct of Operations program at the Idaho Accelerated Retrieval Project Phase II.

300

Cloud Condensation Nuclei Retrievals at Cloud Base in North Dakota  

E-Print Network [OSTI]

Cloud Condensation Nuclei Retrievals at Cloud Base in North Dakota · Mariusz Starzec #12;Motivation Compare University of Wyoming (UWyo) and Droplet Measurement Technologies (DMT) cloud condensation nuclei condensation nuclei concentration (CCNC) at any supersaturation (SS) #12;Background Aerosols act as nuclei

Delene, David J.

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

CRAD, Training- Idaho Accelerated Retrieval Project Phase II  

Broader source: Energy.gov [DOE]

A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2006 Commencement of Operations assessment of the Training Program at the Idaho Accelerated Retrieval Project Phase II.

302

CRAD, Fire Protection- Idaho Accelerated Retrieval Project Phase II  

Broader source: Energy.gov [DOE]

A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2006 Commencement of Operations assessment of the Fire Protection program at the Idaho Accelerated Retrieval Project Phase II.

303

Retrieval of cloud properties using SCIAMACHY on ENVISAT  

E-Print Network [OSTI]

;2 AGENDA 1. Rationale 2. SCIAMACHY and its calibration 3. Algorithms 4. SCIMACHY cloud retrievals 5 Synthetic Aperture Radar (ASAR), operating at C-band, ASAR ensures continuity with the image mode (SAR;13 VICARIOUS CALIBRATION USING MERIS #12;14 MERIS on ENVISAT spacecraft /1.03.2002-present/ · Instrument bands

Kuligowski, Bob

304

Optimally Robust Private Information Retrieval Casey Devet Ian Goldberg  

E-Print Network [OSTI]

of the database. 1 Introduction and related work Private information retrieval (PIR) is a way for a client to look trivial download. The goal of PIR is to transmit less data while still protecting the privacy of the query. PIR is a fundamental building block for many proposed privacy-sensitive applications in the liter

305

Improving the Robustness of Private Information Retrieval Ian Goldberg  

E-Print Network [OSTI]

@cs.uwaterloo.ca Abstract Since 1995, much work has been done creating proto- cols for private information retrieval (PIR). Many variants of the basic PIR model have been proposed, including such modifications as computational. In this paper, we improve on the robustness of PIR in a number of ways. First, we present a Byzantine-robust PIR

Goldberg, Ian

306

Efficient Private File Retrieval by Combining ORAM and PIR  

E-Print Network [OSTI]

Efficient Private File Retrieval by Combining ORAM and PIR Travis Mayberry Erik-Oliver Blass Agnes ORAMs which have worst-case communication complexity linear in their capacity and block size. PIR on the server. This paper presents Path-PIR, a hybrid ORAM construction, using techniques from PIR

307

Single Database Private Information Retrieval with Logarithmic Communication  

E-Print Network [OSTI]

]. Historically, the first 1dPIR scheme was proposed in [KO97], with its security based on the hardness database private information retrieval (1dPIR) is a cryptographic protocol between a database server, who (as otherwise the problem becomes trivial). In addition to its numerous applications [A01], 1dPIR

308

Optimally Robust Private Information Retrieval Casey Devet Ian Goldberg  

E-Print Network [OSTI]

- sponding to the security guarantees they provide. One class is computational PIR [8], in which the database of the database. 1 Introduction and related work Private information retrieval (PIR) is a way for a client to look trivial download. The goal of PIR is to transmit less data while still protecting the privacy of the query

Goldberg, Ian

309

Single Database Private Information Retrieval Implies Oblivious Transfer \\Lambda  

E-Print Network [OSTI]

non­trivial PIR is complete for all two­party and multi­party secure compu­ tations. ffl There exists Crescenzo y Tal Malkin z Rafail Ostrovsky x Abstract A Single­Database Private Information Retrieval (PIR­ munication complexity. We call a PIR protocol non­trivial if its total communication is strictly less than

Ostrovsky, Rafail

310

Single Database Private Information Retrieval Implies Oblivious Transfer  

E-Print Network [OSTI]

Tal Malkinz Rafail Ostrovskyx Abstract A Single-Database Private Information Retrieval PIR- munication complexity. We call a PIR protocol non-trivial if its total communication is strictly less than the size of the database. Non-trivial PIR is an important cryp- tographic primitive with many applications

Ostrovsky, Rafail

311

PIR-Tor: Scalable Anonymous Communication Using Private Information Retrieval  

E-Print Network [OSTI]

architec- ture depends on the security of PIR schemes which are well understood and relatively easy security to that of the Tor net- work. Moreover, our experimental results show that the overhead of PIRPIR-Tor: Scalable Anonymous Communication Using Private Information Retrieval Prateek Mittal1 Femi

Goldberg, Ian

312

Single Database Private Information Retrieval with Logarithmic Communication  

E-Print Network [OSTI]

]. Historically, the first 1dPIR scheme was proposed in [KO97], with its security based on the hardness Single database private information retrieval (1dPIR) is a cryptographic protocol between a database to the user (as otherwise the problem becomes trivial). In addition to its numerous applications [A01], 1dPIR

313

CRAD, Radiological Controls- Idaho Accelerated Retrieval Project Phase II  

Broader source: Energy.gov [DOE]

A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2006 Commencement of Operations assessment of the Radiation Protection Program at the Idaho Accelerated Retrieval Project Phase II.

314

Using Information Extraction to Improve Cross-lingual Document Retrieval  

E-Print Network [OSTI]

, Document Retrieval 1. Introduction A shrinking fraction of the world's Web pages are written in English of this optimization. Specifically, we conducted this study in the context of the "distillation evaluation" of the GALE.S. Government's DARPA GALE program. One of the GALE evaluations (the distillation task) involves responding

315

Resources Annotation, Retrieval and Presentation: a Semantic Annotation Management System  

E-Print Network [OSTI]

Resources Annotation, Retrieval and Presentation: a Semantic Annotation Management System M. Albert@univ-brest.fr ABSTRACT This paper addresses the problem of the management of resources metadata. A variety of responses resources that enable more intelligent information discovery systems [1]. According to [1], a metadata

Paris-Sud XI, Université de

316

CLUSTERED MULTIDIMENSIONAL SCALING FOR EXPLORATION IN INFORMATION RETRIEVAL  

E-Print Network [OSTI]

and even hardly improve the exploration process of datasets assumed to be composed of multiple distinctCLUSTERED MULTIDIMENSIONAL SCALING FOR EXPLORATION IN INFORMATION RETRIEVAL Eniko Sz´ekely, ´Eric: clustering, nearest neighbour, multidimensional scaling, exploration. Abstract: The data that needs

Genève, Université de

317

Automatic Detection of Treatment Relationships for Patent Retrieval  

E-Print Network [OSTI]

Automatic Detection of Treatment Relationships for Patent Retrieval Aaron Chu UCLA Computer Science Department Los Angeles, California 90024 aaronc@ucla.edu Shigeyuki Sakurai1 4 th Patent Examination Department Japan Patent Office Tokyo, Japan sakurai-shigeyuki@jpo.go.jp Alfonso F. Cardenas UCLA Computer

Cárdenas, Alfonso F.

318

CRAD, Emergency Management- Idaho Accelerated Retrieval Project Phase II  

Broader source: Energy.gov [DOE]

A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2006 Commencement of Operations assessment of the Emergency Management program at the Idaho Accelerated Retrieval Project Phase II.

319

CRAD, Occupational Safety & Health- Idaho Accelerated Retrieval Project Phase II  

Broader source: Energy.gov [DOE]

A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2006 Commencement of Operations assessment of the Occupational Safety and Industrial Hygiene Program at the Idaho Accelerated Retrieval Project Phase II.

320

Audio-Visual Multimedia Retrieval on Mobile Iftikhar Ahmad1  

E-Print Network [OSTI]

of devices (hand held phones to personal computers). Mobile devices are not only limited in size, shape devices is a challenge. 8.1 Introduction The amount of personal digital information is increasing8 Audio-Visual Multimedia Retrieval on Mobile Devices Iftikhar Ahmad1 and Moncef Gabbouj2 1 Nokia

Gabbouj, Moncef

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

CRAD, Quality Assurance- Idaho Accelerated Retrieval Project Phase II  

Broader source: Energy.gov [DOE]

A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2006 Commencement of Operations assessment of the Quality Assurance Program at the Idaho Accelerated Retrieval Project Phase II.

322

Project W-211, initial tank retrieval systems, retrieval control system software configuration management plan  

SciTech Connect (OSTI)

This Software Configuration Management Plan (SCMP) provides the instructions for change control of the W-211 Project, Retrieval Control System (RCS) software after initial approval/release but prior to the transfer of custody to the waste tank operations contractor. This plan applies to the W-211 system software developed by the project, consisting of the computer human-machine interface (HMI) and programmable logic controller (PLC) software source and executable code, for production use by the waste tank operations contractor. The plan encompasses that portion of the W-211 RCS software represented on project-specific AUTOCAD drawings that are released as part of the C1 definitive design package (these drawings are identified on the drawing list associated with each C-1 package), and the associated software code. Implementation of the plan is required for formal acceptance testing and production release. The software configuration management plan does not apply to reports and data generated by the software except where specifically identified. Control of information produced by the software once it has been transferred for operation is the responsibility of the receiving organization.

RIECK, C.A.

1999-02-23T23:59:59.000Z

323

From Quantum Mechanics to String Theory  

E-Print Network [OSTI]

types of interactions produces distinctive scattering patterns new particles are produced when the scattering event has enough energy to produce them to get particles up to high energies, experimentalists use generally measure the momenta and energies of particles coming out of a scattering event. From

324

The Battle of the Bulge: Decay of the Thin, False Cosmic String  

E-Print Network [OSTI]

We consider the decay of cosmic strings that are trapped in the false vacuum in a theory of scalar electrodynamics in 3+1 dimensions. We restrict our analysis to the case of thin-walled cosmic strings which occur when large magnetic flux trapped inside the string. Thus the string looks like a tube of fixed radius, at which it is classically stable. The core of the string contains magnetic flux in the true vacuum, while outside the string, separated by a thin wall, is the false vacuum. The string decays by tunnelling to a configuration which is represented by a bulge, where the region of true vacuum within, is ostensibly enlarged. The bulge can be described as the meeting, of a kink soliton anti-soliton pair, along the length of the string. It can be described as a bulge appearing in the initial string, starting from the string of small, classically stable radius, expanding to a fat string of large, classically unstable (to expansion) radius and then returning back to the string of small radius along its length. This configuration is the bounce point of a corresponding O(2) symmetric instanton, which we can determine numerically. Once the bulge appears it explodes in real time. The kink soliton anti-soliton pair recede from each other along the length of the string with a velocity that quickly approaches the speed of light, leaving behind a fat tube. At the same time the radius of the fat tube that is being formed, expands (transversely) as it is no longer classically stable, converting false vacuum to the true vacuum with ever diluting magnetic field within. The rate of this expansion is determined by the energy difference between the true vacuum and the false vacuum. Our analysis could be applied to a network, of cosmic strings formed in the very early universe or vortex lines in a superheated superconductor.

Bum-Hoon Lee; Wonwoo Lee; Richard MacKenzie; M. B. Paranjape; U. A. Yajnik; Dong-han Yeom

2013-10-11T23:59:59.000Z

325

Structured Video: A Data Type with ContentBased Access  

E-Print Network [OSTI]

Structured Video: A Data Type with Content­Based Access Andrzej Duda y Ron Weiss September 1993 MIT: video indexing and searching, video databases, content­ based retrieval, video algebra #12; Abstract We describe structured video, a general video data model allowing free form annotation, composition

Gifford, David K.

326

Structured Video: A Data Type with Content-Based Access  

E-Print Network [OSTI]

Structured Video: A Data Type with Content-Based Access Andrzej Duday Ron Weiss September 1993 MIT or implied, of the Defense Advanced Research Projects Agency or the U.S. Government. #12;Keywords: video indexing and searching, video databases, content- based retrieval, video algebra #12;Abstract We describe

Gifford, David K.

327

Multimodal medical case retrieval using the Dezert-Smarandache theory Quellec Gw nol 1 2  

E-Print Network [OSTI]

history). Indeed, medical experts generally need varied sources of information, which might be incomplete on a classified diabetic retinopathy database. On this database, results are promising: the retrieval precision the retrieval of relevant cases in a case database. The retrieved cases are then used to help interpreting

Paris-Sud XI, Université de

328

An Evaluation of Text Retrieval Methods for Similarity Search of multi-dimensional  

E-Print Network [OSTI]

,1,11,6,2], to the best of our knowledge, no effective similarity search method is known for 2D-NMR-spectra. SimplifiedAn Evaluation of Text Retrieval Methods for Similarity Search of multi-dimensional NMR retrieval method can be applied. We evaluate the performance of two retrieval methods, namely the standard

Hinneburg, Alexander

329

THE THIRD CLOUD RETRIEVAL EVALUATION WORKSHOP What: A joint European/United States workshop  

E-Print Network [OSTI]

THE THIRD CLOUD RETRIEVAL EVALUATION WORKSHOP What: A joint European/United States workshop louds strongly modulate the energy balance of Earth and its atmosphere through their interaction- based cloud retrieval teams to share their experience with state-of-the-art cloud parameter retrievals

Baum, Bryan A.

330

Process Description for the Retrieval of Earth Covered Transuranic (TRU) Waste Containers at the Hanford Site  

SciTech Connect (OSTI)

This document describes process and operational options for retrieval of the contact-handled suspect transuranic waste drums currently stored below grade in earth-covered trenches at the Hanford Site. Retrieval processes and options discussed include excavation, container retrieval, venting, non-destructive assay, criticality avoidance, incidental waste handling, site preparation, equipment, and shipping.

DEROSA, D.C.

2000-01-13T23:59:59.000Z

331

An Investigation of the Latent Semantic Analysis Technique for Document Retrieval  

E-Print Network [OSTI]

An Investigation of the Latent Semantic Analysis Technique for Document Retrieval STUDENT PROJECT;_________________________________________________________________________ An Investigation of the Latent Semantic Analysis Technique for Document Retrieval. Report by: David Mugo Page 2. These term-matching techniques have always relied on matching query terms with document terms to retrieve

332

Extended Combinatorial Constructions for Peer-to-peer User-Private Information Retrieval  

E-Print Network [OSTI]

retrieval (PIR) introduced by Domingo-Ferrer et al. In UPIR, the database knows which records have been information retrieval (PIR). In PIR, the content of a given query is hidden from the database alternative to PIR dubbed user-private information retrieval (UPIR), introduced by Domingo-Ferrer et al. [3

333

fMRI Brain Image Retrieval Based on ICA Components bbai@cs.rutgers.edu  

E-Print Network [OSTI]

fMRI Brain Image Retrieval Based on ICA Components Bing Bai bbai@cs.rutgers.edu Department This manuscript proposes a retrieval system for fMRI brain images. Our goal is to find a similarity- metric to enable us to support queries for "similar tasks" for retrieval on a large collection of brain ex

334

Evaluation of the TORE(R)Lance for Radioactive Waste Mobilization and Retrieval from Underground Storage Tanks  

SciTech Connect (OSTI)

The TORE? Lance is a hand-held hydro transportation device with the ability to convey solids at pre-determined slurry concentrations over great distances. The TORE? Lance head generates a precessing vortex core to mobilize solids. Solids retrieval is accomplished using an eductor. The device contains no parts and requires pressurized fluid to operate the eductor and produce mobilization. Three configurations of TORE? Lance operation were evaluated for mobilization and eduction during these tests: compressed air, water, and an air and water mixture. These tests have shown that the TORE? Lance is a tool that can be used at Hanford for mobilization and retrieval of wastes. The system is versatile and can be configured for many types of applications. These studies showed that the diverse applications require unique solutions so care is recommended for TORE? Lance equipment selection for each application. The two components of the TORE? Lance are the precessing vortex for mobilizing and the eductor for retrieval. The precessing vortex is sensitive to fluid flow rate and pressure. In the hand-held unit these parameters are controlled both internally, by changing shim spacing, and externally by controlling the flow split between the eductor and the head. For in-tank applications out-of-tank control of both these parameters are recommended.

Bamberger, Judith A.; Bates, Cameron J.; Bates, James M.; White, M.

2002-09-25T23:59:59.000Z

335

Investigating the Radiative Impact Clouds Using Retrieved Properties to Classify Cloud Type  

E-Print Network [OSTI]

of Reading, RG6 6AL, UK Abstract. Active remote sensing allows cloud properties such as ice and liquid water remote sensing, Cloud categorization, Cloud properties, Radiative impact. PACS: 92.60. Vb. INTRODUCTION in a radiation scheme which can simulate the radiation budget and heating rates throughout the atmospheric

Hogan, Robin

336

An ARSCL-based cloud type climatology from retrievals and it's use in  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmes Laboratory Site Sustainabilityupgraded

337

EM-50 Tanks Focus Area retrieval process development and enhancements. FY97 technology development summary report  

SciTech Connect (OSTI)

The Retrieval Process Development and Enhancements (RPD and E) activities are part of the US Department of Energy (DOE) EM-50 Tanks Focus Area, Retrieval and Closure program. The purpose of RPD and E is to understand retrieval processes, including emerging and existing technologies, and to gather data on these processes, so that end users have requisite technical bases to make retrieval decisions. Technologies addressed during FY97 include enhancements to sluicing, the use of pulsed air to assist mixing, mixer pumps, innovative mixing techniques, confined sluicing retrieval end effectors, borehole mining, light weight scarification, and testing of Russian-developed retrieval equipment. Furthermore, the Retrieval Analysis Tool was initiated to link retrieval processes with tank waste farms and tank geometric to assist end users by providing a consolidation of data and technical information that can be easily assessed. The main technical accomplishments are summarized under the following headings: Oak Ridge site-gunite and associated tanks treatability study; pulsed air mixing; Oak Ridge site-Old Hydrofracture Facility; hydraulic testbed relocation; cooling coil cleaning end effector; light weight scarifier; innovative tank mixing; advanced design mixer pump; enhanced sluicing; Russian retrieval equipment testing; retrieval data analysis and correlation; simulant development; and retrieval analysis tool (RAT).

Rinker, M.W.; Bamberger, J.A. [Pacific Northwest National Lab., Richland, WA (United States); Alberts, D.G. [Waterjet Technology, Inc., Kent, WA (United States)] [and others

1997-09-01T23:59:59.000Z

338

Radioactive waste shipments to Hanford Retrievable Storage from the General Electric Vallecitos Nuclear Center, Pleasanton, California  

SciTech Connect (OSTI)

During the next two decades the transuranic (TRU) wastes now stored in the burial trenches and storage facilities at the Hanford Site are to be retrieved, processed at the Waste Receiving and Processing Facility, and shipped to the Waste Isolation Pilot Plant near Carlsbad, New Mexico for final disposal. Approximately 3.8% of the TRU waste to be retrieved for shipment to WIPP was generated at the General Electric (GE) Vallecitos Nuclear Center (VNC) in Pleasanton, California and shipped to the Hanford Site for storage. The purpose of this report is to characterize these radioactive solid wastes using process knowledge, existing records, and oral history interviews. The waste was generated almost exclusively from the activities, of the Plutonium Fuels Development Laboratory and the Plutonium Analytical Laboratory. Section 2.0 provides further details of the VNC physical plant, facility operations, facility history, and current status. The solid radioactive wastes were associated with two US Atomic Energy Commission/US Department of Energy reactor programs -- the Fast Ceramic Reactor (FCR) program, and the Fast Flux Test Reactor (FFTR) program. These programs involved the fabrication and testing of fuel assemblies that utilized plutonium in an oxide form. The types and estimated quantities of waste resulting from these programs are discussed in detail in Section 3.0. A detailed discussion of the packaging and handling procedures used for the VNC radioactive wastes shipped to the Hanford Site is provided in Section 4.0. Section 5.0 provides an in-depth look at this waste including the following: weight and volume of the waste, container types and numbers, physical description of the waste, radiological components, hazardous constituents, and current storage/disposal locations.

Vejvoda, E.J.; Pottmeyer, J.A.; DeLorenzo, D.S.; Weyns-Rollosson, M.I. [Los Alamos Technical Associates, Inc., NM (United States); Duncan, D.R. [Westinghouse Hanford Co., Richland, WA (United States)

1993-10-01T23:59:59.000Z

339

Gamma-ray bursts, axion emission and string theory dilaton  

E-Print Network [OSTI]

The emission of axions from supernovae is an interesting possibility to account for the Gamma-Ray Bursts provided their energy can be effectively converted into electromagnetic energy elsewhere. The connection between supernova and gamma-ray bursts has been recently confirmed by the observed correlation between the burst of April 25, 1998 and the supernova SN1998bw. We argue that the axion convertion into photons can be more efficient if one considers the coupling between an intermediate scale axion and the string theory dilaton along with the inclusion of string loops. We also discuss the way dilaton dynamics may allow for a more effective energy exchange with electromagnetic radiation in the expansion process of fireballs.

O. Bertolami

1999-01-14T23:59:59.000Z

340

On the stability of the primordial closed string gas  

E-Print Network [OSTI]

We recast the study of a closed string gas in a toroidal container in the physical situation in which the single string density of states is independent of the volume because energy density is very high. This includes the gas for the well known Brandenberger-Vafa cosmological scenario. We describe the gas in the grandcanonical and microcanonical ensembles. In the microcanonical description, we find a result that clearly confronts the Brandenberger-Vafa calculation to get the specific heat of the system. The important point is that we use the same approach to the problem but a different regularization. By the way, we show that, in the complex temperature formalism, at the Hagedorn singularity, the analytic structure obtained from the so-called F-representation of the free energy coincides with the one computed using the S-representation.

Manuel A. Cobas; M. A. R. Osorio; María Suárez

2006-01-13T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Low-l CMB Power Loss in String Inflation  

E-Print Network [OSTI]

The lack of power on large scales (l < 40) might have been observed by the PLANCK satellite. We argue that this putative feature can be explained by a phase of fast roll at the onset of inflation. We show that in the context of single field models what is required is an asymmetric inflection point model of which fibre inflation is a string motivated example. We study the ability of fibre inflation to generate a suppression of the CMB 2-point function power at low l, finding that the potential derived from string loops is not steep enough for this purpose. We introduce a steeper contribution to the potential, that dominates away from the inflationary region, and show that if properly tuned it can indeed lead to a spectrum with lack of power at large scales.

Francisco G. Pedro; Alexander Westphal

2013-09-13T23:59:59.000Z

342

Integrated Solar Upper Stage (ISUS) thermionic converter string evaluation  

SciTech Connect (OSTI)

A serial string of eighth (8) thermionic converters were performance tested at New Mexico Engineering Research Institute (NMERI) by Frank Wyant et al1. The tests results from the second String Thermionic Assembly Research Testbed (START II) produced less than one half the expected power based on individual converter performance tests. Seven of the eight converters were returned to Lockheed Martin Information Systems-EOS for performance evaluation. Six of the seven produced nominal performance while the seventh converter showed a drastic reduction in performance due to a cesium leak to atmosphere. Several models were proposed to explain why the individual converter performance differed so markedly from the START II serial array. This paper discusses the models, evaluates model validity and compares the models with results from a tow converter serial test using of the returned START II converters.

Talbot, G.J.; Ramsey, W.D.; Chao, C.J.

1998-07-01T23:59:59.000Z

343

A Review of Distributions on the String Landscape  

E-Print Network [OSTI]

We review some basic flux vacua counting techniques and results, focusing on the distributions of properties over different regions of the landscape of string vacua and assessing the phenomenological implications. The topics we discuss include: an overview of how moduli are stabilized and how vacua are counted; the applicability of effective field theory; the uses of and differences between probabilistic and statistical analysis (and the relation to the anthropic principle); the distribution of various parameters on the landscape, including cosmological constant, gauge group rank, and SUSY-breaking scale; "friendly landscapes"; open string moduli; the (in)finiteness of the number of phenomenologically viable vacua; etc. At all points, we attempt to connect this study to the phenomenology of vacua which are experimentally viable.

Jason Kumar

2006-05-24T23:59:59.000Z

344

Secure quantum private information retrieval using phase-encoded queries  

E-Print Network [OSTI]

We propose a quantum solution to the classical private information retrieval (PIR) problem, which allows one to query a database in a private manner. The protocol offers privacy thresholds and allows the user to obtain information from a database in a way that offers the potential adversary, in this model the database owner, no possibility of deterministically establishing the query contents. This protocol may also be viewed as a solution to the symmetrically private information retrieval problem in that it can offer database security (inability for a querying user to steal its contents). Compared to classical solutions, the protocol offers substantial improvement in terms of communication complexity. In comparison with the recent quantum private queries {[}Phys. Rev. Lett. 100, 230502 (2008)] protocol, it is more efficient in terms of communication complexity and the number of rounds, while offering a clear privacy parameter. We discuss the security of the protocol and analyze its strengths and conclude that...

Olejnik, L

2011-01-01T23:59:59.000Z

345

Recommendations on the proposed Monitored Retrievable Storage Facility  

SciTech Connect (OSTI)

Following the Department of Energy's announcement in April 1985 that three Tennessee sites were to be considered for the Monitored Retrievable Storage facility, Governor Lamar Alexander initiated a review of the proposal to be coordinated by his Safe Growth Team. Roane County and the City of Oak Ridge, the local governments sharing jurisdiction over DOE's primary and secondary sites, were invited to participate in the state's review of the MRS proposal. Many issues related to the proposed MRS are being considered by the Governor's Safe Growth Team. The primary objective of the Clinch River MRS Task Force has been to determine whether the proposed Monitored Retrievable Storage facility should be accepted by the local governments, and if so, under what conditions. The Clinch River MRS Task Force is organized into an Executive Committee cochaired by the Roane County Executive and Mayor of Oak Ridge and three Study Groups focusing on environmental (including health and safety), socioeconomic, and transportation issues.

Not Available

1985-10-01T23:59:59.000Z

346

Effective Supergravity from the Weakly Coupled HeteroticString  

SciTech Connect (OSTI)

The motivation for Calabi-Yau-like compactifications of the weakly coupled E{sub 8} {circle_times} E{sub 8} heterotic string theory, its particle spectrum and the issue of dilaton stabilization are briefly reviewed. Modular invariant models for hidden sector condensation and supersymmetry breaking are described at the quantum level of the effective field theory. Their phenomenological and cosmological implications, including a possible origin for R-parity, are discussed.

Gaillard, Mary K.

2005-05-01T23:59:59.000Z

347

Hamilton-Jacobi formalism for string gas thermodynamics  

SciTech Connect (OSTI)

We show that the thermodynamics of a system of strings at high energy densities under the ideal gas approximation has a formulation in terms of the Hamilton-Jacobi theory. The two parameters of the system, which have dimensions of energy density and number density, respectively, define a family of hypersurfaces of a codimension one, which can be described by the vanishing of a function F that plays the role of a Hamiltonian.

Joseph, Anosh [Department of Physics, Syracuse University, Syracuse, New York 13244-1130 (United States); Rajeev, Sarada G. [Department of Physics and Astronomy and Department of Mathematics, University of Rochester, Rochester, New York 14627-0171 (United States)

2009-03-15T23:59:59.000Z

348

Hamilton-Jacobi formalism for string gas thermodynamics  

E-Print Network [OSTI]

We show that the thermodynamics of a system of strings at high energy densities under the ideal gas approximation has a formulation in terms of Hamilton-Jacobi theory. The two parameters of the system, which have dimensions of energy density and number density, respectively, define a family of hypersurfaces of co-dimension one, which can be described by the vanishing of a function F that plays the role of a Hamiltonian.

Anosh Joseph; S. G. Rajeev

2008-07-25T23:59:59.000Z

349

Retrieval process development and enhancements waste simulant compositions and defensibility  

SciTech Connect (OSTI)

The purpose of this report is to document the physical waste simulant development efforts of the EM-50 Tanks Focus Area at the Hanford Site. Waste simulants are used in the testing and development of waste treatment and handling processes because performing such tests using actual tank waste is hazardous and prohibitively expensive. This document addresses the simulant development work that supports the testing of waste retrieval processes using simulants that mimic certain key physical properties of the tank waste. Development and testing of chemical simulants are described elsewhere. This work was funded through the EM-50 Tanks Focus Area as part of the Retrieval Process Development and Enhancements (RPD&E) Project at the Pacific Northwest National Laboratory (PNNL). The mission of RPD&E is to understand retrieval processes, including emerging and existing processes, gather performance data on those processes, and relate the data to specific tank problems to provide end users with the requisite technical bases to make retrieval and closure decisions. Physical simulants are prepared using relatively nonhazardous and inexpensive materials rather than the chemicals known to be in tank waste. Consequently, only some of the waste properties are matched by the simulant. Deciding which properties need to be matched and which do not requires a detailed knowledge of the physics of the process to be tested using the simulant. Developing this knowledge requires reviews of available literature, consultation with experts, and parametric tests. Once the relevant properties are identified, waste characterization data are reviewed to establish the target ranges for each property. Simulants are then developed that possess the desired ranges of properties.

Powell, M.R.; Golcar, G.R.; Geeting, J.G.H.

1997-09-01T23:59:59.000Z

350

System to control contamination during retrieval of buried TRU waste  

DOE Patents [OSTI]

A system to control contamination during the retrieval of hazardous waste comprising an outer containment building, an inner containment building, within the outer containment building, an electrostatic radioactive particle recovery unit connected to and in communication with the inner and outer containment buildings, and a contaminate suppression system including a moisture control subsystem, and a rapid monitoring system having the ability to monitor conditions in the inner and outer containment buildings.

Menkhaus, Daniel E. (Idaho Falls, ID); Loomis, Guy G. (Idaho Falls, ID); Mullen, Carlan K. (Idaho Falls, ID); Scott, Donald W. (Idaho Falls, ID); Feldman, Edgar M. (Idaho Falls, ID); Meyer, Leroy C. (Idaho Falls, ID)

1993-01-01T23:59:59.000Z

351

System to control contamination during retrieval of buried TRU waste  

DOE Patents [OSTI]

A system is described to control contamination during the retrieval of hazardous waste comprising an outer containment building, an inner containment building, within the outer containment building, an electrostatic radioactive particle recovery unit connected to and in communication with the inner and outer containment buildings, and a contaminate suppression system including a moisture control subsystem, and a rapid monitoring system having the ability to monitor conditions in the inner and outer containment buildings.

Menkhaus, D.E.; Loomis, G.G.; Mullen, C.K.; Scott, D.W.; Feldman, E.M.; Meyer, L.C.

1993-04-20T23:59:59.000Z

352

Experiences with string matching on the Fermi Architecture  

SciTech Connect (OSTI)

String matching is at the core of many real-world applications, such as security, bioinformatic, data mining. All these applications requires the ability to match always growing data sets against large dictionaries effectively, fastly and possibly in real time. Unfortunately, string matching is a computationally intensive procedure which poses significant challenges on current software and hardware implementations. Graphic Processing Units (GPU) have become an interesting target for such high-throughput applications, but the algorithms and the data structures need to be redesigned to be parallelized and adapted to the underlining hardware, coping with the limitations imposed by these architectures. In this paper we present an efficient implementation of the Aho-Corasick string matching algorithm on GPU, showing how we progressively redesigned the algorithm and the data structures to fit on the architecture. We then evaluate the implementation on single and multiple Tesla C2050 (T20 ``Fermi'' based) boards, comparing them to the previous Tesla C1060 (T10 based) solutions and equivalent multicore implementations on x86 CPUs. We discuss the various tradeoffs of the different architectures.

Tumeo, Antonino; Secchi, Simone; Villa, Oreste

2011-02-25T23:59:59.000Z

353

Gauge field, strings, solitons, anomalies and the speed of life  

E-Print Network [OSTI]

It's been said that "mathematics is biology's next microscope, only better; biology is mathematics' next physics, only better". Here we aim for something even better. We try to combine mathematical physics and biology into a picoscope of life. For this we merge techniques which have been introduced and developed in modern mathematical physics, largely by Ludvig Faddeev to describe objects such as solitons and Higgs and to explain phenomena such as anomalies in gauge fields. We propose a synthesis that can help to resolve the protein folding problem, one of the most important conundrums in all of science. We apply the concept of gauge invariance to scrutinize the extrinsic geometry of strings in three dimensional space. We evoke general principles of symmetry in combination with Wilsonian universality and derive an essentially unique Landau-Ginzburg energy that describes the dynamics of a generic string-like configuration in the far infrared. We observe that the energy supports topological solitons, that pertain to an anomaly in the manner how a string is framed around its inflection points. We explain how the solitons operate as modular building blocks from which folded proteins are composed. We describe crystallographic protein structures by multi-solitons with experimental precision, and investigate the non-equilibrium dynamics of proteins under varying temperature. We simulate the folding process of a protein at in vivo speed and with close to pico-scale accuracy using a standard laptop computer: With pico-biology as mathematical physics' next pursuit, things can only get better.

Antti J. Niemi

2014-07-05T23:59:59.000Z

354

CERN Winter School on Supergravity, Strings, and Gauge Theory 2010  

ScienceCinema (OSTI)

The CERN Winter School on Supergravity, Strings, and Gauge Theory is the analytic continuation of the yearly training school of the former EC-RTN string network "Constituents, Fundamental Forces and Symmetries of the Universe". The 2010 edition of the school is supported and organized by the CERN Theory Divison, and will take place from Monday January 25 to Friday January 29, at CERN. As its predecessors, this school is meant primarily for training of doctoral students and young postdoctoral researchers in recent developments in theoretical high-energy physics and string theory. The programme of the school will consist of five series of pedagogical lectures, complemented by tutorial discussion sessions in the afternoons. Previous schools in this series were organized in 2005 at SISSA in Trieste, and in 2006, 2007, 2008, and 2009 at CERN, Geneva. Other similar schools have been organized in the past by the former related RTN network "The Quantum Structure of Spacetime and the Geometric Nature of Fundamental Interactions". This edition of the school is not funded by the European Union. The school is funded by the CERN Theory Division, and the Arnold Sommerfeld Center at Ludwig-Maximilians University of Munich. Scientific committee: M. Gaberdiel, D. Luest, A. Sevrin, J. Simon, K. Stelle, S. Theisen, A. Uranga, A. Van Proeyen, E. Verlinde Local organizers: A. Uranga, J. Walcher

None

2011-10-06T23:59:59.000Z

355

Constraints on cosmic strings from the LIGO-Virgo gravitational-wave detectors  

E-Print Network [OSTI]

Cosmic strings can give rise to a large variety of interesting astrophysical phenomena. Among them, powerful bursts of gravitational waves (GWs) produced by cusps are a promising observational signature. In this Letter we present a search for GWs from cosmic string cusps in data collected by the LIGO and Virgo gravitational wave detectors between 2005 and 2010, with over 625 days of live time. We find no evidence of GW signals from cosmic strings. From this result, we derive new constraints on cosmic string parameters, which complement and improve existing limits from previous searches for a stochastic background of GWs from cosmic microwave background measurements and pulsar timing data. In particular, if the size of loops is given by the gravitational backreaction scale, we place upper limits on the string tension $G\\mu$ below $10^{-8}$ in some regions of the cosmic string parameter space.

J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; P. Ajith; B. Allen; A. Allocca; E. Amador Ceron; D. Amariutei; R. A. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. Ast; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; D. Barker; S. H. Barnum; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; I. Belopolski; G. Bergmann; J. M. Berliner; D. Bersanetti; A. Bertolini; D. Bessis; J. Betzwieser; P. T. Beyersdorf; T. Bhadbhade; I. A. Bilenko; G. Billingsley; J. Birch; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; M. Blom; O. Bock; T. P. Bodiya; M. Boer; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; J. Bowers; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; C. A. Brannen; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; T. Bulik; H. J. Bulten; A. Buonanno; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; J. Calderón Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavagliá; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; M. Colombini; M. Constancio Jr.; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. W. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; K. Craig; J. D. E. Creighton; T. D. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; G. Debreczeni; J. Degallaix; W. Del Pozzo; E. Deleeuw; S. Deléglise; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; M. Díaz; A. Dietz; K. Dmitry; F. Donovan; K. L. Dooley; S. Doravari; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edwards; A. Effler; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endröczi; R. Essick; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; S. Farinon; B. Farr; W. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. Fisher; R. Flaminio; E. Foley; S. Foley; E. Forsi; N. Fotopoulos; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; J. Garcia; F. Garufi; N. Gehrels; G. Gemme; E. Genin; A. Gennai; L. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; P. Groot; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. E. Gushwa; E. K. Gustafson; R. Gustafson; B. Hall; E. Hall; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. Heefner; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; T. Horrom; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; Z. Hua; V. Huang; E. A. Huerta; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; J. Iafrate; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; Y. J. Jang; P. Jaranowski; F. Jiménez-Forteza; W. W. Johnson; D. Jones; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; Haris K; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kaufman; K. Kawabe; S. Kawamura; F. Kawazoe

2014-04-07T23:59:59.000Z

356

Conformal Transformations and Strings for an Accelerating Quark-Antiquark Pair in AdS3  

E-Print Network [OSTI]

From a simple moving open string solution dual to a moving heavy quark with constant velocity in the Poincare AdS_3 spacetime, we construct an accerlerating open string solution dual to a heavy quark-antiquark pair accelerated in opposite directions by performing the three mappings such as the SL(2,R)_L x SL(2,R)_R isometry transformation, the special conformal transformation and the conformal SO(2,2) transformation. Using the string sigma model action we construct two open string solutions staying in two different regions whose dividing line is associated with the event horizon appeared on the string worldsheet and obtain the accelerating open string solution by gluing two such solutions.

Shijong Ryang

2014-12-08T23:59:59.000Z

357

Resonant acoustic transducer and driver system for a well drilling string communication system  

DOE Patents [OSTI]

The acoustic data communication system includes an acoustic transmitter and receiver wherein low frequency acoustic waves, propagating in relatively loss free manner in well drilling string piping, are efficiently coupled to the drill string and propagate at levels competitive with the levels of noise generated by drilling machinery also present in the drill string. The transmitting transducer incorporates a mass-spring piezoelectric transmitter and amplifier combination that permits self-oscillating resonant operation in the desired low frequency range.

Chanson, Gary J. (Weston, MA); Nicolson, Alexander M. (Concord, MA)

1981-01-01T23:59:59.000Z

358

Alternate retrieval technology demonstrations program - test report (ARD Environmental, Inc.)  

SciTech Connect (OSTI)

A prototype vehicle, control system, and waste and water scavenging system were designed and fabricated with essentially the full capabilities of the vehicle system proposed by ARD Environmental. A test tank mockup, including riser and decontamination chamber were designed and fabricated, and approximately 830 cubic feet of six varieties of waste simulants poured. The tests were performed by ARD Environmental personnel at its site in Laurel, Maryland, from 4/22/97 through 5/2/97. The capabilities tested were deployment and retrieval, extended mobility and productivity, the ability to operate the system using video viewing only, retrieval after simulated failure, and retrieval and decontamination. Testing commenced with deployment of the vehicle into the tank. Deployment was accomplished using a crane and auxiliary winch to position the vehicle and lower it through the decontamination chamber, into the 36`` diameter x 6` high riser, and touch down on the waste field in the tank. The initial mobility tests were conducted immediately after deployment, prior to sluicing, as the waste field exhibited the greatest amount of variation at this time. This test demonstrated the ability of the vehicle to maneuver over the simulated waste field, and the ability of the operator to work with only video viewing available. In addition, the ability of the vehicle to right itself after being turned on its side was demonstrated. The production rate was evaluated daily through the testing period by measuring the surface and estimating the amount of material removed. The test demonstrated the ability of the vehicle to reduce the waste surface using 400 psi (nominal) water jets, scavenge water and material from the work area, and move to any location, even in the relatively confined space of the 20` diameter test tank. In addition, the ability to sluice to a remote scavenging module was demonstrated. The failure mode test demonstrated the ability to retrieve a stuck vehicle by pulling on the tether, even if the vehicle wheels were locked or the vehicle was on its side. Line pull required to retrieve the vehicle was measured, and side load on the riser calculated from the line pull and line angles. Finally, the decontamination test demonstrated the ability to effectively clean the umbilical and vehicle. The issues addressed and resolved during the testing were: Feasibility of deploying a vehicle- based system, mobility, production rate and limitation of water in the tank during sluicing, mining strategy, operator efficiency, vehicle recovery, and decontamination. Water usage and waste removal rates were used to estimate the time and water usage requirements for cleaning a Hanford SST.

Berglin, E.J.

1997-07-31T23:59:59.000Z

359

Robustness of phase retrieval methods in x-ray phase contrast imaging: A comparison  

SciTech Connect (OSTI)

Purpose: The robustness of the phase retrieval methods is of critical importance for limiting and reducing radiation doses involved in x-ray phase contrast imaging. This work is to compare the robustness of two phase retrieval methods by analyzing the phase maps retrieved from the experimental images of a phantom. Methods: Two phase retrieval methods were compared. One method is based on the transport of intensity equation (TIE) for phase contrast projections, and the TIE-based method is the most commonly used method for phase retrieval in the literature. The other is the recently developed attenuation-partition based (AP-based) phase retrieval method. The authors applied these two methods to experimental projection images of an air-bubble wrap phantom for retrieving the phase map of the bubble wrap. The retrieved phase maps obtained by using the two methods are compared. Results: In the wrap's phase map retrieved by using the TIE-based method, no bubble is recognizable, hence, this method failed completely for phase retrieval from these bubble wrap images. Even with the help of the Tikhonov regularization, the bubbles are still hardly visible and buried in the cluttered background in the retrieved phase map. The retrieved phase values with this method are grossly erroneous. In contrast, in the wrap's phase map retrieved by using the AP-based method, the bubbles are clearly recovered. The retrieved phase values with the AP-based method are reasonably close to the estimate based on the thickness-based measurement. The authors traced these stark performance differences of the two methods to their different techniques employed to deal with the singularity problem involved in the phase retrievals. Conclusions: This comparison shows that the conventional TIE-based phase retrieval method, regardless if Tikhonov regularization is used or not, is unstable against the noise in the wrap's projection images, while the AP-based phase retrieval method is shown in these experiments to be superior to the TIE-based method for the robustness in performing the phase retrieval.

Yan, Aimin; Wu, Xizeng; Liu, Hong [Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama 35233 (United States); Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States)

2011-09-15T23:59:59.000Z

360

Report on ignitability testing of flammable gasses in a core sampling drill string  

SciTech Connect (OSTI)

This document describes the results from testing performed at the Pittsburgh Research Center to determine the effects of an ignition of flammable gasses contained in a core sampling drill string. Testing showed that 1) An ignition of stoichiometric hydrogen and air in a vented 30 or 55 ft length of drill string will not force 28`` or more of water out the bottom of the drill string, and 2) An ignition of this same gas mixture will not rupture a vented or completely sealed drill string.

Witwer, K.S., Westinghouse Hanford

1996-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

U-092: Sudo Format String Bug Lets Local Users Gain Elevated Privileges  

Broader source: Energy.gov [DOE]

A local user can supply a specially crafted command line argument to trigger a format string flaw and execute arbitrary commands on the target system with root privileges.

362

Aspects of Born-Infeld Theory and String/M-Theory  

E-Print Network [OSTI]

These notes provide a hopefully pedagogic introduction to Born-Infeld theory and some of its uses in String/M-Theory from the perspective of some-one interested in spacetime geometry. Causality and the consequences of having both the open string and closed string metric are stressed. This leads to some new insighst into old problems, such as strings at finite temperature. Various strong coupling limits of both Born-Infeld and the M5-brane theories are described and their relevance for tachyon condensations are mentioned.

Gibbons, G W

2001-01-01T23:59:59.000Z

363

E-Print Network 3.0 - accelerator system string Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

of a desired acoustic system Efficient... for nearly lossless distributed wave media (strings, tubes, rods, membranes, plates, vocal tract, ) Losses Source: Smith...

364

How do A-train Sensors Intercompare in the Retrieval of Above-Cloud Aerosol Optical Depth? A Case Study-based Assessment  

SciTech Connect (OSTI)

We inter-compare the above-cloud aerosol optical depth (ACAOD) of biomass burning plumes retrieved from different A-train sensors, i.e., MODIS, CALIOP, POLDER, and OMI. These sensors have shown independent capabilities to detect and retrieve aerosol loading above marine boundary layer clouds--a kind of situation often found over the Southeast Atlantic Ocean during dry burning season. A systematic one-to-one comparison reveals that, in general, all passive sensors and CALIOP-based research methods derive comparable ACAOD with differences mostly within 0.2 over homogeneous cloud fields. The 532-nm ACAOD retrieved by CALIOP operational algorithm is largely underestimated; however, it’s 1064-nm AOD when converted to 500 nm shows closer agreement to the passive sensors. Given the different types of sensor measurements processed with different algorithms, the close agreement between them is encouraging. Due to lack of adequate direct measurements above cloud, the validation of satellite-based ACAOD retrievals remains an open challenge. The inter-satellite comparison, however, can be useful for the relative evaluation and consistency check.

Jethva, H. T.; Torres, O.; Waquet, F.; Chand, Duli; Hu, Yong X.

2014-01-16T23:59:59.000Z

365

A Novel Retrieval Algorithm for Cloud Optical Properties from the Atmopsheric Radiation Measurement Program's Two-Channel Narrow-Field-of-View Radiometer  

SciTech Connect (OSTI)

Cloud optical depth is the most important of all cloud optical properties, and vital for any cloud-radiation parameterization. To estimate cloud optical depth, the atmospheric science community has widely used ground-based flux measurements from either broadband or narrowband radiometers in the past decade. However, this type of technique is limited to overcast conditions and, at best, gives us an "effective" cloud optical depth instead of its "local" value. Unlike flux observations, monochromatic narrow-field-of-view (NFOV) radiance measurements contain information of local cloud properties, but unfortunately, the use of radiance to interpret optical depth suffers from retrieval ambiguity. We have pioneered an algorithm to retrieve cloud optical depth in a fully three-dimensional cloud situation using new Atmospheric Radiation Measurement (ARM) ground-based passive two-channel (673 and 870 nm) NFOV measurements. The underlying principle of the algorithm is that these two channels have similar cloud properties but strong spectral contrast in surface reflectance. This algorthm offers the first opportunity to illustrate cloud evolution with high temporal resolution retrievals. A combination of two-channel NFOV radiances with multi-filter rotating shadowband radiometer (MFRSR) fluxes for the retrieval of cloud optical properties is also discussed.

Wiscombe, Warren J.; Marshak, A.; Chiu, J.-Y. C.; Knyazikhin, Y.; Barnard, James C.; Luo, Yi

2005-03-14T23:59:59.000Z

366

MANAGEMENT OF TRANSURANIC (TRU) WASTE RETRIEVAL PROJECT RISKS SUCCESSES IN THE STARTUP OF THE HANFORD 200 AREA TRU WASTE RETRIEVAL PROJECT  

SciTech Connect (OSTI)

A risk identification and mitigation method applied to the Transuranic (TRU) Waste Retrieval Project performed at the Hanford 200 Area burial grounds is described. Retrieval operations are analyzed using process flow diagramming. and the anticipated project contingencies are included in the Authorization Basis and operational plans. Examples of uncertainties assessed include degraded container integrity, bulged drums, unknown containers, and releases to the environment. Identification and mitigation of project risks contributed to the safe retrieval of over 1700 cubic meters of waste without significant work stoppage and below the targeted cost per cubic meter retrieved. This paper will be of interest to managers, project engineers, regulators, and others who are responsible for successful performance of waste retrieval and other projects with high safety and performance risks.

GREENWLL, R.D.

2005-01-20T23:59:59.000Z

367

Title I design summary report, initial tank retrieval systems, project W-211  

SciTech Connect (OSTI)

This document provides the Title I (preliminary) design for the Tank 241-SY-101 (101-SY) retrieval system. The design reflects an integrated retrieval approach for 101-SY, whereby the existing mitigation pump will be used to mix the waste and Project W-211 will provide for waste removal. The Title I Design Summary Report includes narrative and sketches that describe the technical aspect of the project, as well as updated cost and schedule baselines for the 101-SY retrieval system.

Rieck, C.A.

1995-03-01T23:59:59.000Z

368

Remote Handled Transuranic Sludge Retrieval Transfer And Storage System At Hanford  

SciTech Connect (OSTI)

This paper describes the systems developed for processing and interim storage of the sludge managed as remote-handled transuranic (RH-TRU). An experienced, integrated CH2M HILL/AFS team was formed to design and build systems to retrieve, interim store, and treat for disposal the K West Basin sludge, namely the Sludge Treatment Project (STP). A system has been designed and is being constructed for retrieval and interim storage, namely the Engineered Container Retrieval, Transfer and Storage System (ECRTS).

Raymond, Rick E. [CH2M HILL Plateau Remediation Company, Richland, WA (United States); Frederickson, James R. [AREVA, Avignon (France); Criddle, James [AREVA, Avignon (France); Hamilton, Dennis [CH2M HILL Plateau Remediation Company, Richland, WA (United States); Johnson, Mike W. [CH2M HILL Plateau Remediation Company, Richland, WA (United States)

2012-10-18T23:59:59.000Z

369

Ground-Based Remote Retrievals of Cumulus Entrainment Rates  

SciTech Connect (OSTI)

While fractional entrainment rates for cumulus clouds have typically been derived from airborne observations, this limits the size and scope of available data sets. To increase the number of continental cumulus entrainment rate observations available for study, an algorithm for retrieving them from ground-based remote sensing observations has been developed. This algorithm, called the Entrainment Rate In Cumulus Algorithm (ERICA), uses the suite of instruments at the Southern Great Plains (SGP) site of the United States Department of Energy's Atmospheric Radiation Measurement (ARM) Climate Research Facility as inputs into a Gauss-Newton optimal estimation scheme, in which an assumed guess of the entrainment rate is iteratively adjusted through intercomparison of modeled liquid water path and cloud droplet effective radius to their observed counterparts. The forward model in this algorithm is the Explicit Mixing Parcel Model (EMPM), a cloud parcel model that treats entrainment as a series of discrete entrainment events. A quantified value for measurement uncertainty is also returned as part of the retrieval. Sensitivity testing and information content analysis demonstrate the robust nature of this method for retrieving accurate observations of the entrainment rate without the drawbacks of airborne sampling. Results from a test of ERICA on three months of shallow cumulus cloud events show significant variability of the entrainment rate of clouds in a single day and from one day to the next. The mean value of 1.06 km-ą for the entrainment rate in this dataset corresponds well with prior observations and simulations of the entrainment rate in cumulus clouds.

Wagner, Timothy J.; Turner, David D.; Berg, Larry K.; Krueger, Steven K.

2013-07-26T23:59:59.000Z

370

Rapid automatic keyword extraction for information retrieval and analysis  

DOE Patents [OSTI]

Methods and systems for rapid automatic keyword extraction for information retrieval and analysis. Embodiments can include parsing words in an individual document by delimiters, stop words, or both in order to identify candidate keywords. Word scores for each word within the candidate keywords are then calculated based on a function of co-occurrence degree, co-occurrence frequency, or both. Based on a function of the word scores for words within the candidate keyword, a keyword score is calculated for each of the candidate keywords. A portion of the candidate keywords are then extracted as keywords based, at least in part, on the candidate keywords having the highest keyword scores.

Rose, Stuart J (Richland, WA); Cowley,; Wendy E (Richland, WA); Crow, Vernon L (Richland, WA); Cramer, Nicholas O (Richland, WA)

2012-03-06T23:59:59.000Z

371

Integral Monitored Retrievable Storage (MRS) Facility conceptual design report  

SciTech Connect (OSTI)

In April 1985, the Department of Energy (DOE) selected the Clinch River site as its preferred site for the construction and operation of the monitored retrievable storage (MRS) facility (USDOE, 1985). In support of the DOE MRS conceptual design activity, available data describing the site have been gathered and analyzed. A composite geotechnical description of the Clinch River site has been developed and is presented herein. This report presents Clinch River site description data in the following sections: general site description, surface hydrologic characteristics, groundwater characteristics, geologic characteristics, vibratory ground motion, surface faulting, stability of subsurface materials, slope stability, and references. 48 refs., 35 figs., 6 tabs.

None

1985-09-01T23:59:59.000Z

372

Stratus Cloud Drizzle Retrieval During SHEBA from MMCR Doppler Moments  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administrationcontroller systemsBiSiteNeutronStrategic Plan The strategicIDrizzle Retrieval During

373

E-Print Network 3.0 - adaptive information retrieval Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Engine Support for Software Applications Summary: search is very different than the ad-hoc, interactive search that information retrieval research... & Subject Descriptors:...

374

Can a Workspace Help to Overcome the Query Formulation Problem in Image Retrieval?  

E-Print Network [OSTI]

Urban,J. Jose,J.M. Proceedings of the 28th European Conference on Information Retrieval (ECIR'06) pp 385â??396 Springer Verlag

Urban, J.

375

Year Report (FY 2000) Evaluation of uncertainties in satellite retrievals of aerosol  

E-Print Network [OSTI]

. Third Year Statement of Work 1. Construct clean aerosol data sets for the Mauna Loa (Hawaii), and Cheeka retrievals to the observed variability of ae

376

E-Print Network 3.0 - aerosol retrieval algorithms Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the scavenging... site provide retrievals of aerosol, cloud, precipitation and radiative heating in the Arctic? 12;Key... profiles derived from ground-based and satellite remote...

377

Turing's Landscape: decidability, computability and complexity in string theory  

E-Print Network [OSTI]

I argue that questions of algorithmic decidability, computability and complexity should play a larger role in deciding the "ultimate" theoretical description of the Landscape of string vacua. More specifically, I examine the notion of the average rank of the (unification) gauge group in the Landscape, the explicit construction of Ricci-flat metrics on Calabi-Yau manifolds as well as the computability of fundamental periods to show that undecidability questions are far more pervasive than that described in the work of Denef and Douglas.

Abhijnan Rej

2009-09-10T23:59:59.000Z

378

Nonlocal String Tachyon as a Model for Cosmological Dark Energy  

SciTech Connect (OSTI)

There are many different phenomenological models describing the cosmological dark energy and accelerating Universe by choosing adjustable functions. In this paper we consider a specific model of scalar tachyon field which is derived from the NSR string field theory and study its cosmological applications. We find that in the effective field theory approximation the equation of state parameter w < -1, i.e. one has a phantom Universe. It is shown that due to nonlocal effects there is no quantum instability that the usual phantom models suffer from. Moreover due to a flip effect of the potential the Universe does not enter to a future singularity.

Aref'eva, Irina Ya. [Steklov Mathematical Institute, Russian Academy of Sciences, Gubkin st. 8, Moscow, 119991 (Russian Federation)

2006-03-29T23:59:59.000Z

379

Refined Topological Strings and Toric Calabi-Yau Threefolds  

E-Print Network [OSTI]

The refined topological vertex formulation computes the refined topological string partition function for non-compact toric Calabi-Yau threefolds which engineer N=2 supersymmetric gauge theories. For geometries such as the local P^2, which do not give rise to gauge theories, the refined topological vertex alone is not sufficient for directly calculating the refined amplitudes. In this paper, we extend the refined topological vertex formalism and propose a complementary new vertex which, together with the refined topological vertex, determines the refined amplitudes for all toric Calabi-Yau threefolds.

Amer Iqbal; Can Kozcaz

2012-10-10T23:59:59.000Z

380

Exact results on ABJ theory and the refined topological string  

E-Print Network [OSTI]

We study the partition function of the ABJ theory, which is the N=6 superconformal Chern-Simons matter theory with gauge group U(N)xU(N+M) and Chern-Simons levels (k,-k). We exactly compute the ABJ partition function on a three sphere for various k, M and N via the Fermi gas approach. By using these exact data, we show that the ABJ partition function is completely determined by the refined topological string on local P^1 x P^1, including membrane instanton effects in the M-theory dual.

Masazumi Honda; Kazumi Okuyama

2014-07-22T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

System and method for damping vibration in a drill string  

DOE Patents [OSTI]

A system for damping vibration in a drill string can include a valve assembly having a supply of a fluid, a first member, and a second member capable of moving in relation to first member in response to vibration of the drill bit. The first and second members define a first and a second chamber for holding the fluid. Fluid can flow between the first and second chambers in response to the movement of the second member in relation to the first member. The valve assembly can also include a coil or a valve for varying a resistance of the fluid to flow between the first and second chambers.

Wassell, Mark Ellsworth; Turner, William Evans; Burgess, Daniel E; Perry, Carl Allison

2014-03-04T23:59:59.000Z

382

String black hole: Can it be a particle accelerator ?  

E-Print Network [OSTI]

In this paper we have studied the possibility of the center-of-mass energy of two particles colliding near the horizon of a static charged black hole in string theory. Various cases corresponding to the electric charge and the angular momentum of the particles were considered. The studies were done for the general black hole as well as for the extreme black hole. There were two scenarios where the center-of-mass energy reach very large values if the appropriate properties of the particles are chosen.

Sharmanthie Fernando

2014-08-21T23:59:59.000Z

383

Absorption of scalars by extremal black holes in string theory  

E-Print Network [OSTI]

We show that the low frequency absorption cross section of minimally coupled massless scalar fields by extremal spherically symmetric black holes in d dimensions in the presence of string-theoretical alpha' corrections is equal to the horizon area. Classically one has the relation sigma=4GS between the absorption cross section and the black hole entropy. We discuss the validity of such relation in the presence of alpha' corrections for extremal black holes, both nonsupersymmetric and supersymmetric. The examples we consider seem to indicate that this relation is verified in the presence of alpha' corrections for supersymmetric black holes, but not for nonsupersymmetric ones.

Filipe Moura

2014-06-13T23:59:59.000Z

384

Production and detection of relic dilatons in string cosmology  

E-Print Network [OSTI]

This paper summarizes the contribution presented at the {\\sl IX Marcel Grossmann Meeting} (Rome, July 2000). It is stressed, in particular, that a non-relativistic background of ultra-light dilatons, produced in the context of string cosmology, could represent today a significant fraction of cold dark matter. If the dilaton mass lies within the resonant band of present gravitational antennas, a stochastic dilaton background with a nearly critical density could be visible, in principle, already at the level of sensitivity of the detectors in operation and presently under construction.

M. Gasperini

2000-09-28T23:59:59.000Z

385

Self-Gravitating Non-Abelian Cosmic String Solution  

E-Print Network [OSTI]

The coupled Einstein-Yang-Mills equations on a time dependent axially symmetric spacetime are investigated, without a priori any conditions on the gauge field. There is numerical evidence for the existence of a regular solution with the desired asymptotic features. Just as in the supermassive abelian counterpart model, the formation of a singularity at finite distance of the core of the string depends critically on a parameter of the model, i.e., the constant value of one of the magnetic components of the YM potentials. The multiple-scale method could supply decisive answers concerning the stability of the solution.

Reinoud J. Slagter

1998-09-15T23:59:59.000Z

386

Property:Incentive/ExpireDtString | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy ResourcesLoadingPenobscot County,ContAddr2 Jump to: navigation, searchExpireDtString Jump to: navigation,

387

Physics 5B Winter 2009 Rate of Energy Transfer by Sinusoidal Waves on a String  

E-Print Network [OSTI]

, Vibrations and Waves (W.W. Norton and Company, New York, 1971). First, we compute the kinetic energyPhysics 5B Winter 2009 Rate of Energy Transfer by Sinusoidal Waves on a String Consider the kinetic energy and the potential energy of this string segment due to the passage of a traveling wave

California at Santa Cruz, University of

388

DRILL-STRING NONLINEAR DYNAMICS ACCOUNTING FOR DRILLING FLUID T. G. Ritto  

E-Print Network [OSTI]

DRILL-STRING NONLINEAR DYNAMICS ACCOUNTING FOR DRILLING FLUID T. G. Ritto R. Sampaio thiagoritto Descartes, 77454 Marne-la-Vallée, France Abstract. The influence of the drilling fluid (or mud) on the drill in the analysis of the nonlinear dynamics of a drill-string. The aim of this paper is to investigate how the fluid

Boyer, Edmond

389

Geodesic motion in the space-time of cosmic strings interacting via magnetic fields  

E-Print Network [OSTI]

We study the geodesic motion of test particles in the space-time of two Abelian-Higgs strings interacting via their magnetic fields. These bound states of cosmic strings constitute a field theoretical realization of p-q-strings which are predicted by inflationary models rooted in String Theory, e.g. brane inflation. In contrast to previously studied models describing p-q-strings our model possesses a Bogomolnyi-Prasad-Sommerfield (BPS) limit. If cosmic strings exist it would be exciting to detect them by direct observation. We propose that this can be done by the observation of test particle motion in the space-time of these objects. In order to be able to make predictions we have to solve the field equations describing the configuration as well as the geodesic equation numerically. The geodesics can then be classified according to the test particle's energy, angular momentum and momentum along the string axis. We find that the interaction of two Abelian-Higgs strings can lead to the existence of bound orbits that would be absent without the interaction. We also discuss the minimal and maximal radius of orbits and comment on possible applications in the context of gravitational wave emission.

Betti Hartmann; Valeria Kagramanova

2012-07-25T23:59:59.000Z

390

ELECTRON STRING SOURCE OF HIGHLY CHARGED IONS: STUDIES AND THE FIRST TEST ON A SYNCHROTRON  

E-Print Network [OSTI]

ELECTRON STRING SOURCE OF HIGHLY CHARGED IONS: STUDIES AND THE FIRST TEST ON A SYNCHROTRON E. D, MSL, 104 05 Stockholm, Sweden Abstract Operation of an electron beam ion source (EBIS) in the reflex mode at certain conditions leads to formation of the so called electron string state of one component

391

Fractal Properties and Small-scale Structure of Cosmic String Networks  

E-Print Network [OSTI]

We present results from a detailed numerical study of the small-scale and loop production properties of cosmic string networks, based on the largest and highest resolution string simulations to date. We investigate the non-trivial fractal properties of cosmic strings, in particular, the fractal dimension and renormalised string mass per unit length, and we also study velocity correlations. We demonstrate important differences between string networks in flat (Minkowski) spacetime and the two very similar expanding cases. For high resolution matter era network simulations, we provide strong evidence that small-scale structure has converged to `scaling' on all dynamical lengthscales, without the need for other radiative damping mechanisms. We also discuss preliminary evidence that the dominant loop production size is also approaching scaling.

C. J. A. P. Martins; E. P. S. Shellard

2005-11-29T23:59:59.000Z

392

Monitored Retrievable Storage System Requirements Document. Revision 1  

SciTech Connect (OSTI)

This Monitored Retrievable Storage System Requirements Document (MRS-SRD) describes the functions to be performed and technical requirements for a Monitored Retrievable Storage (MRS) facility subelement and the On-Site Transfer and Storage (OSTS) subelement. The MRS facility subelement provides for temporary storage, at a Civilian Radioactive Waste Management System (CRWMS) operated site, of spent nuclear fuel (SNF) contained in an NRC-approved Multi-Purpose Canister (MPC) storage mode, or other NRC-approved storage modes. The OSTS subelement provides for transfer and storage, at Purchaser sites, of spent nuclear fuel (SNF) contained in MPCs. Both the MRS facility subelement and the OSTS subelement are in support of the CRWMS. The purpose of the MRS-SRD is to define the top-level requirements for the development of the MRS facility and the OSTS. These requirements include design, operation, and decommissioning requirements to the extent they impact on the physical development of the MRS facility and the OSTS. The document also presents an overall description of the MRS facility and the OSTS, their functions (derived by extending the functional analysis documented by the Physical System Requirements (PSR) Store Waste Document), their segments, and the requirements allocated to the segments. In addition, the top-level interface requirements of the MRS facility and the OSTS are included. As such, the MRS-SRD provides the technical baseline for the MRS Safety Analysis Report (SAR) design and the OSTS Safety Analysis Report design.

Not Available

1994-03-01T23:59:59.000Z

393

Secure quantum private information retrieval using phase-encoded queries  

SciTech Connect (OSTI)

We propose a quantum solution to the classical private information retrieval (PIR) problem, which allows one to query a database in a private manner. The protocol offers privacy thresholds and allows the user to obtain information from a database in a way that offers the potential adversary, in this model the database owner, no possibility of deterministically establishing the query contents. This protocol may also be viewed as a solution to the symmetrically private information retrieval problem in that it can offer database security (inability for a querying user to steal its contents). Compared to classical solutions, the protocol offers substantial improvement in terms of communication complexity. In comparison with the recent quantum private queries [Phys. Rev. Lett. 100, 230502 (2008)] protocol, it is more efficient in terms of communication complexity and the number of rounds, while offering a clear privacy parameter. We discuss the security of the protocol and analyze its strengths and conclude that using this technique makes it challenging to obtain the unconditional (in the information-theoretic sense) privacy degree; nevertheless, in addition to being simple, the protocol still offers a privacy level. The oracle used in the protocol is inspired both by the classical computational PIR solutions as well as the Deutsch-Jozsa oracle.

Olejnik, Lukasz [CERN, 1211 Geneva 23, Switzerland and Poznan Supercomputing and Networking Center, Noskowskiego 12/14, PL-61-704 Poznan (Poland)

2011-08-15T23:59:59.000Z

394

Recommendations on the proposed Monitored Retrievable Storage Facility  

SciTech Connect (OSTI)

Following the Department of Energy`s announcement in April 1985 that three Tennessee sites were to be considered for the Monitored Retrievable Storage facility, Governor Lamar Alexander initiated a review of the proposal to be coordinated by his Safe Growth Team. Roane County and the City of Oak Ridge, the local governments sharing jurisdiction over DOE`s primary and secondary sites, were invited to participate in the state`s review of the MRS proposal. Many issues related to the proposed MRS are being considered by the Governor`s Safe Growth Team. The primary objective of the Clinch River MRS Task Force has been to determine whether the proposed Monitored Retrievable Storage facility should be accepted by the local governments, and if so, under what conditions. The Clinch River MRS Task Force is organized into an Executive Committee cochaired by the Roane County Executive and Mayor of Oak Ridge and three Study Groups focusing on environmental (including health and safety), socioeconomic, and transportation issues.

Not Available

1985-10-01T23:59:59.000Z

395

Minimal Liouville Gravity correlation numbers from Douglas string equation  

E-Print Network [OSTI]

We continue the study of $(q,p)$ Minimal Liouville Gravity with the help of Douglas string equation. We generalize the results of \\cite{Moore:1991ir}, \\cite{Belavin:2008kv}, where Lee-Yang series $(2,2s+1)$ was studied, to $(3,3s+p_0)$ Minimal Liouville Gravity, where $p_0=1,2$. We demonstrate that there exist such coordinates $\\tau_{m,n}$ on the space of the perturbed Minimal Liouville Gravity theories, in which the partition function of the theory is determined by the Douglas string equation. The coordinates $\\tau_{m,n}$ are related in a non-linear fashion to the natural coupling constants $\\lambda_{m,n}$ of the perturbations of Minimal Lioville Gravity by the physical operators $O_{m,n}$. We find this relation from the requirement that the correlation numbers in Minimal Liouville Gravity must satisfy the conformal and fusion selection rules. After fixing this relation we compute three- and four-point correlation numbers when they are not zero. The results are in agreement with the direct calculations in Minimal Liouville Gravity available in the literature \\cite{Goulian:1990qr}, \\cite{Zamolodchikov:2005sj}, \\cite{Belavin:2006ex}.

Alexander Belavin; Boris Dubrovin; Baur Mukhametzhanov

2014-09-11T23:59:59.000Z

396

Gravitating superconducting strings with timelike or spacelike currents  

E-Print Network [OSTI]

We construct gravitating superconducting string solutions of the U(1)_{local} x U(1)_{global} model solving the coupled system of Einstein and matter field equations numerically. We study the properties of these solutions in dependence on the ratio between the symmetry breaking scale and the Planck mass. Using the macroscopic stability conditions formulated by Carter, we observe that the coupling to gravity allows for a new stable region that is not present in the flat space-time limit. We match the asymptotic metric to the Kasner metric and show that the relations between the Kasner coefficients and the energy per unit length and tension suggested previously are well fulfilled for symmetry breaking scale much smaller than the Planck mass. We also study the solutions to the geodesic equation in this space-time. While geodesics in the exterior space-time of standard cosmic strings are just straight lines, test particles experience a force in a general Kasner space-time and as such bound orbits are possible.

Betti Hartmann; Florent Michel

2012-08-20T23:59:59.000Z

397

Stringent phenomenological investigation into heterotic string optical unification  

SciTech Connect (OSTI)

For the weakly coupled heterotic string (WCHS) there is a well-known factor of 20 conflict between the minimum string coupling unification scale, {lambda}{sub H}{approx}5x10{sup 17} GeV, and the projected minimal supersymmetric standard model (MSSM) gauge coupling unification scale, {lambda}{sub U}{approx}2.5x10{sup 16} GeV, assuming an intermediate scale desert (ISD). From a bottom-up approach, renormalization effects of intermediate scale MSSM-charged exotics (ISME), which are endemic to quasirealistic string models, can resolve this issue by pushing the MSSM scale up to the string scale. However, for a generic string model, this implies that the projected {lambda}{sub U} unification under the ISD assumption is accidental. If the true unification scale is {lambda}{sub H} > or approx. 5.0x10{sup 17} GeV, is it possible that an illusionary unification at {lambda}{sub U}=2.5x10{sup 17} GeV in the ISD scenario is not accidental? (This is an issue recently raised again by Binetruy et al..) Optical unification suggests that {lambda}{sub U} might not be accidental. Through its ISME constraints, optical unification offers a mechanism whereby a generic MSSM scale {lambda}{sub U}<{lambda}{sub H} is guaranteed. A WCHS model was recently constructed that could yield optical unification, depending on the availability of anomaly-cancelling D- and F-flat directions that meet optical unification ISME requirements. We report the results of a systematic investigation of the optical unification properties of a subset of flat directions of this model that are stringently flat. Stringent flat directions do not require significant fine-tuning and can be easily guaranteed to be F-flat to all finite order (or to at least a given finite order consistent with electroweak scale supersymmetry breaking). They are the likely roots of more complicated (and arguably, more finely tuned) flat directions. To realize optical unification, a flat direction must keep all exotic triplets and doublets massless down to an intermediate mass scale, except for three extra pairs of Higgs which must acquire MSSM (or higher) scale mass. Additionally, six out of seven pairs of exotic hypercharged non-Abelian singlets must acquire MSSM (or higher) scale mass, while the remaining pair remains massless down to the intermediate scale. Our investigation revealed that the best stringent directions could induce MSSM scale or higher mass to at most three of the six pairs of exotic singlets, and to only two out of three pairs of exotic Higgs. Each of these stringent flat directions keeps all of the exotic triplets and remaining exotic doublets massless down to an intermediate scale. Thus, some fine-tuning away from stringent flat directions is necessary, if it is possible for an additional three pairs of exotic hypercharged singlets and one more pair of extra Higgs to become MSSM scale massive. Future research may indicate if such flat directions exist. This paper is a product of the 2003-2004 NSF REU program at Baylor University.

Perkins, J.; Dundee, B.; Obousy, R.; Cleaver, G. [Center for Astrophysics, Space Physics and Engineering Research Department of Physics, Baylor University, Waco, Texas 76798-7316 (United States); Hatten, S. [Center for Astrophysics, Space Physics and Engineering Research Department of Physics, Baylor University, Waco, Texas 76798-7316 (United States); Walla Walla College, 204 South College Avenue, College Place, Washington 99324 (United States); Kasper, E. [Center for Astrophysics, Space Physics and Engineering Research Department of Physics, Baylor University, Waco, Texas 76798-7316 (United States); Department of Physics, Texas A and M University, College Station, Texas 77843-4242 (United States); Robinson, M. [Center for Astrophysics, Space Physics and Engineering Research Department of Physics, Baylor University, Waco, Texas 76798-7316 (United States); Department of Physics, Auburn University, Auburn, Alabama 36849 (United States); Sloan, C. [Center for Astrophysics, Space Physics and Engineering Research Department of Physics, Baylor University, Waco, Texas 76798-7316 (United States); Department of Physics, College of Charleston, Charleston, South Carolina 29424 (United States); Stone, K. [Center for Astrophysics, Space Physics and Engineering Research Department of Physics, Baylor University, Waco, Texas 76798-7316 (United States); Department of Physics, East Tennessee State University, Johnson City, Tennessee 37614 (United States)

2007-01-15T23:59:59.000Z

398

Green's function retrieval from reflection data, in absence of a receiver at the virtual source position  

E-Print Network [OSTI]

Green's function retrieval from reflection data, in absence of a receiver at the virtual source; accepted 6 March 2014) The methodology of Green's function retrieval by cross-correlation has led to many, a virtual source is created at the position of a receiver. Here a method is discussed for Green's function

Snieder, Roel

399

Incremental Cluster-Based Retrieval using Compressed Cluster-Skipping Inverted Files  

E-Print Network [OSTI]

Incremental Cluster-Based Retrieval using Compressed Cluster-Skipping Inverted Files ISMAIL SENGOR ________________________________________________________________________ We propose a unique cluster-based retrieval (CBR) strategy using a new cluster-skipping inverted file for improving query processing efficiency. The new inverted file incorporates cluster membership and centroid

Can, Fazli

400

Introduction Inverted index Processing Boolean queries Query optimization Course overview Introduction to Information Retrieval  

E-Print Network [OSTI]

Introduction Inverted index Processing Boolean queries Query optimization Course overview Retrieval 1 / 60 #12;Introduction Inverted index Processing Boolean queries Query optimization Course overview Take-away Sch¨utze: Boolean Retrieval 2 / 60 #12;Introduction Inverted index Processing Boolean

Nejdl, Wolfgang

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Incremental Cluster-Based Retrieval Using Compressed Cluster-Skipping Inverted Files  

E-Print Network [OSTI]

15 Incremental Cluster-Based Retrieval Using Compressed Cluster-Skipping Inverted Files ISMAIL cluster-based retrieval (CBR) strategy using a new cluster-skipping inverted file for improving query processing efficiency. The new inverted file incorporates cluster member- ship and centroid information along

Ulusoy, Ă?zgĂĽr

402

Cut Graph Based Information Storage and Retrieval in 3D Sensor Networks with General Topology  

E-Print Network [OSTI]

curve with the guaranteed success to retrieve aggregated data through time and space with one and a balanced traffic load. I. INTRODUCTION This research focuses on in-network data-centric informa- tion along a curve called replication curve, and a query travels along another curve called retrieval curve

Wu, Hongyi

403

Satellite observations of ozone and nitrogen dioxide: from retrievals to emission estimates  

E-Print Network [OSTI]

Summary Satellite observations of ozone and nitrogen dioxide: from retrievals to emission estimates be inferred for important trace gases such as ozone (O3) and nitrogen dioxide (NO2). Chemical transport models.11 to 3.79. Total nitrogen dioxide columns can be retrieved from space in the 405­465 nm window

Haak, Hein

404

Indirect validation of tropospheric nitrogen dioxide retrieved from the OMI satellite instrument: Insight into the seasonal  

E-Print Network [OSTI]

Click Here for Full Article Indirect validation of tropospheric nitrogen dioxide retrieved from nitrogen dioxide retrieved from the OMI satellite instrument: Insight into the seasonal variation of the hydroxyl radical (OH). Nitrogen dioxide (NO2) is an indicator of surface air quality that is associated

Dirksen, Ruud

405

MULTIMODAL MEDICAL CASE RETRIEVAL USING BAYESIAN NETWORKS AND THE DEZERT-SMARANDACHE THEORY  

E-Print Network [OSTI]

and medical history). Indeed, medical experts gene- rally need varied sources of information, which might is evaluated on a classified diabetic retinopathy database. On this database, results are promising the retrieval of relevant cases in a case database. The retrieved cases are then used to help interpreting

Paris-Sud XI, Université de

406

Seismic source mechanisms of tremor recorded on Arenal volcano, Costa Rica, retrieved by waveform inversion.  

E-Print Network [OSTI]

1 Seismic source mechanisms of tremor recorded on Arenal volcano, Costa Rica, retrieved by waveform.M. Mora4 , G.J Soto.5 1 Seismology and Computational Rock Physics Laboratory, School of Geological performed for a common source location, the position of which was retrieved through the evaluation

Boyer, Edmond

407

Effects of Usage based Feedback on Video Retrieval: a Simulation based Study1  

E-Print Network [OSTI]

Effects of Usage based Feedback on Video Retrieval: a Simulation based Study1 DAVID VALLET ________________________________________________________________________ We present a model for exploiting community based usage information for video retrieval, where implicit usage information from past users is exploited in order to provide enhanced assistance in video

408

Retrieval of optical and microphysical properties of ice clouds using Atmospheric Radiation Measurement (ARM) data  

E-Print Network [OSTI]

is based on a method proposed by Yang et al. (2005). The research examines single-layer ice clouds in the midlatitude and polar regions. The retrieved information in the midlatitudes is then verified using retrievals from the Moderate-resolution Imaging...

Kinney, Jacqueline Anne

2005-11-01T23:59:59.000Z

409

Integrating an automatic classification method into the medical image retrieval process  

E-Print Network [OSTI]

the performance of the University at Buffalo Medical Text and Images Retrieval System (UBMedTIRS). This paper classification process was performed using the Image Retrieval for Medical Application (IRMA) codes3 employed to acquire the image such as x-ray, ultrasound, magnetic resonance measurement, nuclear medicine

Ruiz, Miguel E.

410

SCALAR WIND SPEED AND DIRECTION TROPICAL CYCLONE RETRIEVALS FOR CONICAL SCANNING SCATTEROMETERS  

E-Print Network [OSTI]

SCALAR WIND SPEED AND DIRECTION TROPICAL CYCLONE RETRIEVALS FOR CONICAL SCANNING SCATTEROMETERS--Scatterometer measurements of ocean vector winds (OVW) are significantly degraded in the presence of the precipitation, especially in tropical cyclones. This paper presents a new ocean hurricane/typhoon wind vector retrieval

Hennon, Christopher C.

411

PageFetch: A Retrieval Game for Children (and Adults) Jim Purvis, Leif Azzopardi  

E-Print Network [OSTI]

.e. the higher the rank the more points), and unlike 1 Pages were selected using trending search terms for under and Subject Descriptors: H.3.3 [Information Storage and Retrieval]: Information Search and Retrieval General Terms: Design, Human Factors Keywords: Human Computational Games EXTENDED ABSTRACT Children often

Jose, Joemon M.

412

A Database Architecture For Real-Time Motion Retrieval Charly Awad, Nicolas Courty and Sylvie Gibet  

E-Print Network [OSTI]

A Database Architecture For Real-Time Motion Retrieval Charly Awad, Nicolas Courty and Sylvie Gibet, leading to an ex- ponential growth of the size of motion databases. Conse- quently indexing, querying, and retrieving motion capture data have become important considerations in the usability of such databases. Our

Paris-Sud XI, Université de

413

Single-Database Private Information Retrieval Protocols : Overview, Usability and Trends.  

E-Print Network [OSTI]

1 Single-Database Private Information Retrieval Protocols : Overview, Usability and Trends. Carlos in which a user retrieves a record out of N from a replicated database, while hiding from the database interesting sub-field of research, called single- database PIR, deals with the schemes that allow a user

Paris-Sud XI, Université de

414

Private Information Retrieval by Keywords Benny Chor \\Lambda Niv Gilboa y Moni Naor z  

E-Print Network [OSTI]

Private information retrieval (PIR) schemes enable a user to access one or more servers that hold copies or computational sense) on the identity of the item retrieved by the user. All known PIR schemes assume underlying PIR scheme (including single server schemes). The transformation requires no modification

415

Reducing the Servers' Computation in Private Information Retrieval: PIR with Preprocessing  

E-Print Network [OSTI]

Reducing the Servers' Computation in Private Information Retrieval: PIR with Preprocessing Amos Beimel Yuval Ishai Tal Malkin§ June 12, 2003 Abstract Private information retrieval (PIR) enables a user if the user requires only a single bit. In this paper, we study the computational complexity of PIR. We show

Beimel, Amos

416

Outsourced Private Information Retrieval with Pricing and Access Control Yizhou Huang  

E-Print Network [OSTI]

- tion Retrieval (PIR) to untrusted servers while protect- ing the privacy of the database owner as well as that of the database clients. We observe that by layering PIR on top of an Oblivious RAM (ORAM) data layout, we provide.65 seconds and answers a PIR query within 3.5 seconds. 1 Introduction Private Information Retrieval, or PIR

Goldberg, Ian

417

Reducing the Servers' Computation in Private Information Retrieval: PIR with Preprocessing  

E-Print Network [OSTI]

Reducing the Servers' Computation in Private Information Retrieval: PIR with Preprocessing #3; Amos Beimel y Yuval Ishai z Tal Malkin x June 9, 2003 Abstract Private information retrieval (PIR) enables of PIR. We show that in the standard PIR model, where the servers hold only the database, linear

Beimel, Amos

418

The Design of PIRS, a Peer-to-Peer Information Retrieval System  

E-Print Network [OSTI]

The Design of PIRS, a Peer-to-Peer Information Retrieval System Wai Gen Yee and Ophir Frieder of Technology Chicago, IL 60616 yee@iit.edu, ophir@ir.iit.edu Abstract. We describe the design of PIRS, a peer-to-peer information retrieval system. Unlike some other proposed approaches, PIRS does not require the centralization

419

Reducing the Servers' Computation in Private Information Retrieval: PIR with Preprocessing  

E-Print Network [OSTI]

Reducing the Servers' Computation in Private Information Retrieval: PIR with Preprocessing #3; Amos Beimel y Yuval Ishai z Tal Malkin x January 26, 2006 Abstract Private information retrieval (PIR) enables of PIR. We show that in the standard PIR model, where the servers hold only the database, linear

Ishai, Yuval

420

Efficient Private Information Retrieval Using Secure Xiangyao Yu, Christopher W. Fletcher  

E-Print Network [OSTI]

attention from the cryptography and security communities. Two main approaches to solve PIR have appearedEfficient Private Information Retrieval Using Secure Hardware Xiangyao Yu, Christopher W. Fletcher, marten, devadas}@mit.edu ABSTRACT Existing crypto-based Private Information Retrieval (PIR) schemes

Gummadi, Ramakrishna

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

rPIR: Ramp Secret Sharing based Communication Efficient Private Information Retrieval  

E-Print Network [OSTI]

Information Retrieval) is a promising security primitive to protect the privacy of users' interests. PIRrPIR: Ramp Secret Sharing based Communication Efficient Private Information Retrieval Lichun Li/diseases from a stock/medical database leaks sensitive information to the database server. PIR (Private

422

On the Computational Practicality of Private Information Retrieval Network Security and Applied Cryptography Lab  

E-Print Network [OSTI]

On the Computational Practicality of Private Information Retrieval Radu Sion Network Security of single-server computational pri- vate information retrieval (PIR) for the purpose of preserv- ing client access patterns leakage. We show that deployment of non-trivial single server PIR protocols on real

Carbunar, Bogdan

423

Almost Optimal Private Information Retrieval Dmitri Asonov ? and JohannChristoph Freytag  

E-Print Network [OSTI]

information retrieval (PIR) protocol allows a user to retrieve one of N records from a database while hiding the identity of the record from the database server. With the initially proposed PIR protocols to process of these solutions is off­line communication, com­ parable to the size of the entire database. Using a secure

Freytag, Johann-Christoph

424

Unified Green's function retrieval by cross-correlation; connection with energy principles Roel Snieder,1,  

E-Print Network [OSTI]

Unified Green's function retrieval by cross-correlation; connection with energy principles Roel and observationally that the Green's function for acoustic and elastic waves can be retrieved by cross-correlating fluctuations recorded at two locations. We extend the concept of the extraction of the Green's function

Snieder, Roel

425

IR Principles for Content-based Indexing and Retrieval of Functional Brain Images  

E-Print Network [OSTI]

IR Principles for Content-based Indexing and Retrieval of Functional Brain Images Bing Bai, Paul cornea, silver@ece.rutgers.edu ABSTRACT In this paper, we explore the concept of a "library of brain images", which implies not only a repository of brain images, but also efficient search and retrieval

426

Uncertainties in using the hodograph method to retrieve gravity wave characteristics from individual soundings  

E-Print Network [OSTI]

Uncertainties in using the hodograph method to retrieve gravity wave characteristics from individual soundings Fuqing Zhang and Shuguang Wang Department of Atmospheric Sciences, Texas A&M University] The hodograph method is commonly used to retrieve inertio-gravity wave characteristics from individual vertical

Plougonven, Riwal

427

3D MODEL RETRIEVAL BASED ON DEPTH LINE DESCRIPTOR Mohamed Chaouch and Anne Verroust-Blondet  

E-Print Network [OSTI]

3D MODEL RETRIEVAL BASED ON DEPTH LINE DESCRIPTOR Mohamed Chaouch and Anne Verroust-Blondet INRIA.verroust}@inria.fr. ABSTRACT In this paper, we propose a novel 2D/3D approach for 3D model matching and retrieving. Each model information provides a more accurate description of 3D shape boundaries than using other 2D shape descriptors

Paris-Sud XI, Université de

428

Efficient 3D shape matching and retrieval using a concrete radialized spherical projection representation  

E-Print Network [OSTI]

Efficient 3D shape matching and retrieval using a concrete radialized spherical projection We present a 3D shape retrieval methodology based on the theory of spherical harmonics. Using PCA on the face normals of the model. The 3D model is decomposed into a set of spherical functions

Paris-Sud XI, Université de

429

3D Human Video Retrieval: from Pose to Motion Matching R. Slama1,2  

E-Print Network [OSTI]

3D Human Video Retrieval: from Pose to Motion Matching R. Slama1,2 , H. Wannous1,2 and M. Daoudi2, France Abstract 3D video retrieval is a challenging problem lying at the heart of many primary research areas in computer graph- ics and computer vision applications. In this paper, we present a new 3D human

Paris-Sud XI, Université de

430

On 3D retrieval from photos Tarik Filali Ansary, Jean-Phillipe Vandeborre, Mohamed Daoudi  

E-Print Network [OSTI]

On 3D retrieval from photos Tarik Filali Ansary, Jean-Phillipe Vandeborre, Mohamed Daoudi FOX}@enic.fr http://www-rech.enic.fr/fox-miire Abstract In this paper, we propose a method for 3D-model retrieval from one or more photos. This method provides an "opti- mal" selection of 2D views to represent a 3D

Vandeborre, Jean-Philippe

431

Retrievals of mixed-phase cloud properties during the National Polar-Orbiting Operational Environmental  

E-Print Network [OSTI]

Retrievals of mixed-phase cloud properties during the National Polar-Orbiting Operational/Visible Infrared Imaging Radiometer Suite (VIIRS) to retrieve pixel-level mixed-phase cloud optical thicknesses Satellite Observations Validation Project (C3VP), were analyzed. The performance of the mixed-phase

Liou, K. N.

432

EnviroMic: Towards Cooperative Storage and Retrieval in Audio Sensor Networks  

E-Print Network [OSTI]

1 EnviroMic: Towards Cooperative Storage and Retrieval in Audio Sensor Networks Liqian Luo, Qing at Urbana-Champaign, mpward@uiuc.edu Abstract This paper presents the design, implementation, and evaluation of EnviroMic, a novel distributed acoustic monitoring, storage, and trace retrieval system. Audio represents

Stankovic, John A.

433

Unsupervised and semi-supervised morphological analysis for Information Retrieval in the biomedical  

E-Print Network [OSTI]

Unsupervised and semi-supervised morphological analysis for Information Retrieval in the biomedical.Claveau@irisa.fr Abstract In the biomedical field, the key to access information is the use of specialized terms. However to improve biomedical Information Retrieval. We present an approach combining an automatic alignment using

Boyer, Edmond

434

Q-Winds satellite hurricane wind retrievals and H*Wind comparisons  

E-Print Network [OSTI]

tailored to extreme wind events. Because of this and precipitation effects, scatterometers have failed/passive scatterometer retrieval algorithm designed specifically for extreme wind events, hereafter identified1 Q-Winds satellite hurricane wind retrievals and H*Wind comparisons Pet Laupattarakasem and W

Hennon, Christopher C.

435

Cross-language information retrieval using PARAFAC2.  

SciTech Connect (OSTI)

A standard approach to cross-language information retrieval (CLIR) uses Latent Semantic Analysis (LSA) in conjunction with a multilingual parallel aligned corpus. This approach has been shown to be successful in identifying similar documents across languages - or more precisely, retrieving the most similar document in one language to a query in another language. However, the approach has severe drawbacks when applied to a related task, that of clustering documents 'language-independently', so that documents about similar topics end up closest to one another in the semantic space regardless of their language. The problem is that documents are generally more similar to other documents in the same language than they are to documents in a different language, but on the same topic. As a result, when using multilingual LSA, documents will in practice cluster by language, not by topic. We propose a novel application of PARAFAC2 (which is a variant of PARAFAC, a multi-way generalization of the singular value decomposition [SVD]) to overcome this problem. Instead of forming a single multilingual term-by-document matrix which, under LSA, is subjected to SVD, we form an irregular three-way array, each slice of which is a separate term-by-document matrix for a single language in the parallel corpus. The goal is to compute an SVD for each language such that V (the matrix of right singular vectors) is the same across all languages. Effectively, PARAFAC2 imposes the constraint, not present in standard LSA, that the 'concepts' in all documents in the parallel corpus are the same regardless of language. Intuitively, this constraint makes sense, since the whole purpose of using a parallel corpus is that exactly the same concepts are expressed in the translations. We tested this approach by comparing the performance of PARAFAC2 with standard LSA in solving a particular CLIR problem. From our results, we conclude that PARAFAC2 offers a very promising alternative to LSA not only for multilingual document clustering, but also for solving other problems in cross-language information retrieval.

Bader, Brett William; Chew, Peter; Abdelali, Ahmed (New Mexico State University, Las Cruces, NM); Kolda, Tamara Gibson

2007-05-01T23:59:59.000Z

436

Next-Generation Search Engines for Information Retrieval  

SciTech Connect (OSTI)

In the recent years, there have been significant advancements in the areas of scientific data management and retrieval techniques, particularly in terms of standards and protocols for archiving data and metadata. Scientific data is rich, and spread across different places. In order to integrate these pieces together, a data archive and associated metadata should be generated. Data should be stored in a format that can be retrievable and more importantly it should be in a format that will continue to be accessible as technology changes, such as XML. While general-purpose search engines (such as Google or Bing) are useful for finding many things on the Internet, they are often of limited usefulness for locating Earth Science data relevant (for example) to a specific spatiotemporal extent. By contrast, tools that search repositories of structured metadata can locate relevant datasets with fairly high precision, but the search is limited to that particular repository. Federated searches (such as Z39.50) have been used, but can be slow and the comprehensiveness can be limited by downtime in any search partner. An alternative approach to improve comprehensiveness is for a repository to harvest metadata from other repositories, possibly with limits based on subject matter or access permissions. Searches through harvested metadata can be extremely responsive, and the search tool can be customized with semantic augmentation appropriate to the community of practice being served. One such system, Mercury, a metadata harvesting, data discovery, and access system, built for researchers to search to, share and obtain spatiotemporal data used across a range of climate and ecological sciences. Mercury is open-source toolset, backend built on Java and search capability is supported by the some popular open source search libraries such as SOLR and LUCENE. Mercury harvests the structured metadata and key data from several data providing servers around the world and builds a centralized index. The harvested files are indexed against SOLR search API consistently, so that it can render search capabilities such as simple, fielded, spatial and temporal searches across a span of projects ranging from land, atmosphere, and ocean ecology. Mercury also provides data sharing capabilities using Open Archive Initiatives Protocol for Metadata Handling (OAI-PMH). In this paper we will discuss about the best practices for archiving data and metadata, new searching techniques, efficient ways of data retrieval and information display.

Devarakonda, Ranjeet [ORNL; Hook, Leslie A [ORNL; Palanisamy, Giri [ORNL; Green, James M [ORNL

2011-01-01T23:59:59.000Z

437

IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 24, NO. 10, OCTOBER 2006 1793 A Memory-Efficient Parallel String Matching  

E-Print Network [OSTI]

--Computer network security, finite automata, parallel processing, site security monitoring, string matching. I

Liu, Yunhao

438

Changes in Tropical Rainfall Measuring Mission (TRMM) retrievals due to the orbit boost estimated from rain gauge data  

E-Print Network [OSTI]

in precipitation retrievals from the satellite data alone. We estimate changes in TRMM Microwave Imager (TMI) and the Precipitation Radar (PR) precipitation retrievals due to the orbit boost by comparing them with surface rain gauges on ocean buoys operated...

DeMoss, Jeremy

2009-06-02T23:59:59.000Z

439

Collective String Interactions in AdS/QCD and High-Multiplicity pA Collisions  

E-Print Network [OSTI]

QCD strings originate from high-energy scattering in the form of Reggions and Pomerons, and have been studied in some detail in lattice numerical simulations. Production of multiple strings, with their subsequent breaking, is now a mainstream model of high energy $pp$ and $pA$ collisions. Recent LHC experiments revealed that high multiplicity end of such collisions show interesting collective effects. This ignited an interest in the interaction of QCD strings and multi-string dynamics. Holographic models, collectively known as AdS/QCD, developed in the last decade, describe both hadronic spectroscopy and basic thermodynamics, but so far no studies of the QCD strings have been done in this context. The subject of this paper is to do this. First, we study in more detail the scalar sector of hadronic spectroscopy, identifying "glueballs" and "scalar mesons," and calculate the degree of their mixing. The QCD strings, holographic images of the fundamental strings, thus have a "gluonic core" and a "sigma cloud." Th...

Iatrakis, Ioannis; Shuryak, Edward

2015-01-01T23:59:59.000Z

440

Using Context to Improve the Evaluation of Information Retrieval Systems  

E-Print Network [OSTI]

The crucial role of the evaluation in the development of the information retrieval tools is useful evidence to improve the performance of these tools and the quality of results that they return. However, the classic evaluation approaches have limitations and shortcomings especially regarding to the user consideration, the measure of the adequacy between the query and the returned documents and the consideration of characteristics, specifications and behaviors of the search tool. Therefore, we believe that the exploitation of contextual elements could be a very good way to evaluate the search tools. So, this paper presents a new approach that takes into account the context during the evaluation process at three complementary levels. The experiments gives at the end of this article has shown the applicability of the proposed approach to real research tools. The tests were performed with the most popular searching engine (i.e. Google, Bing and Yahoo) selected in particular for their high selectivity. The obtaine...

Bouramoul, Abdelkrim; Doan, Bich-Lien; 10.5121/ijdms.2011.3202

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

CONSTRAINING THE STRING GAUGE FIELD BY GALAXY ROTATION CURVES AND PERIHELION PRECESSION OF PLANETS  

SciTech Connect (OSTI)

We discuss a cosmological model in which the string gauge field coupled universally to matter gives rise to an extra centripetal force and will have observable signatures on cosmological and astronomical observations. Several tests are performed using data including galaxy rotation curves of 22 spiral galaxies of varied luminosities and sizes and perihelion precessions of planets in the solar system. The rotation curves of the same group of galaxies are independently fit using a dark matter model with the generalized Navarro-Frenk-White (NFW) profile and the string model. A remarkable fit of galaxy rotation curves is achieved using the one-parameter string model as compared to the three-parameter dark matter model with the NFW profile. The average {chi}{sup 2} value of the NFW fit is 9% better than that of the string model at a price of two more free parameters. Furthermore, from the string model, we can give a dynamical explanation for the phenomenological Tully-Fisher relation. We are able to derive a relation between field strength, galaxy size, and luminosity, which can be verified with data from the 22 galaxies. To further test the hypothesis of the universal existence of the string gauge field, we apply our string model to the solar system. Constraint on the magnitude of the string field in the solar system is deduced from the current ranges for any anomalous perihelion precession of planets allowed by the latest observations. The field distribution resembles a dipole field originating from the Sun. The string field strength deduced from the solar system observations is of a similar magnitude as the field strength needed to sustain the rotational speed of the Sun inside the Milky Way. This hypothesis can be tested further by future observations with higher precision.

Cheung, Yeuk-Kwan E.; Xu Feng, E-mail: cheung@nju.edu.cn [Department of Physics, Nanjing University, 22 Hankou Road, Nanjing 210093 (China)

2013-09-01T23:59:59.000Z

442

The Gunite and Associated Tanks Remediation Project Tank Waste Retrieval Performance and Lessons Learned, vol. 1 [of 2  

SciTech Connect (OSTI)

The Gunite and Associated Tanks (GAAT) Remediation Project was the first of its kind performed in the United States. Robotics and remotely operated equipment were used to successfully transfer almost 94,000 gal of remote-handled transuranic sludge containing over 81,000 Ci of radioactive contamination from nine large underground storage tanks at the Oak Ridge National Laboratory (ORNL). The sludge was transferred with over 439,000 gal of radioactive waste supernatant and {approx}420,500 gal of fresh water that was used in sluicing operations. The GAATs are located in a high-traffic area of ORNL near a main thoroughfare. A phased and integrated approach to waste retrieval operations was used for the GAAT Remediation Project. The project promoted safety by obtaining experience from low-risk operations in the North Tank Farm before moving to higher-risk operations in the South Tank Farm. This approach allowed project personnel to become familiar with the tanks and waste, as well as the equipment, processes, procedures, and operations required to perform successful waste retrieval. By using an integrated approach to tank waste retrieval and tank waste management, the project was completed years ahead of the original baseline schedule, which resulted in avoiding millions of dollars in associated costs. This report is organized in two volumes. Volume 1 provides information on the various phases of the GAAT Remediation Project. It also describes the different types of equipment and how they were used. The emphasis of Volume 1 is on the description of the tank waste retrieval performance and the lessons learned during the GAAT Remediation Project. Volume 2 provides the appendixes for the report, which include the following information: (A) Background Information for the Gunite and Associated Tanks Operable Unit; (B) Annotated Bibliography; (C) Comprehensive Listing of the Sample Analysis Data from the GAAT Remediation Project; (D) GAAT Equipment Matrix; and (E) Vendor List for the GAAT Remediation Project. The remediation of the GAATs was completed {approx}5.5 years ahead of schedule and {approx}$120,435,000 below the cost estimated in the Remedial Investigation/Feasibility Study for the project. These schedule and cost savings were a direct result of the selection and use of state-of-the-art technologies and the dedication and drive of the engineers, technicians, managers, craft workers, and support personnel that made up the GAAT Remediation Project Team.

Lewis, BE

2003-10-07T23:59:59.000Z

443

Occupational dose estimates for a monitored retrievable storage facility  

SciTech Connect (OSTI)

Occupational doses were estimated for radiation workers at the monitored retrievable storage (MRS) facility. This study provides an estimate of the occupational dose based on the current MRS facility design, examines the extent that various design parameters and assumptions affect the dose estimates, and identifies the areas and activities where exposures can be reduced most effectively. Occupational doses were estimated for both the primary storage concept and the alternate storage concept. The dose estimates indicate the annual dose to all radiation workers will be below the 5 rem/yr federal dose equivalent limit. However, the estimated dose to most of the receiving and storage crew (the workers responsible for the receipt, storage, and surveillance of the spent fuel and its subsequent retrieval), to the crane maintenance technicians, and to the cold and remote maintenance technicians is above the design objective of 1 rem/yr. The highest annual dose is received by the riggers (4.7 rem) in the receiving and storage crew. An indication of the extent to which various design parameters and assumptions affect the dose estimates was obtained by changing various design-based assumptions such as work procedures, background dose rates in radiation zones, and the amount of fuel received and stored annually. The study indicated that a combination of remote operations, increased shielding, and additional personnel (for specific jobs) or changes in operating procedures will be necessary to reduce worker doses below 1.0 rem/yr. Operations that could be made at least partially remote include the removal and replacement of the tiedowns, impact limiters, and personnel barriers from the shipping casks and the removal or installation of the inner closure bolts. Reductions of the background dose rates in the receiving/shipping and the transfer/discharge areas may be accomplished with additional shielding.

Harty, R.; Stoetzel, G.A.

1986-06-01T23:59:59.000Z

444

Hawking radiation as tunneling from charged black holes in 0A string theory  

E-Print Network [OSTI]

There has been much work on explaining Hawking radiation as a quantum tunneling process through horizons. Basically, this intuitive picture requires the calculation of the imaginary part of the action for outgoing particle. And two ways are known for achieving this goal: the null-geodesic method and the Hamilton-Jacobi method. We apply these methods to the charged black holes in 2D dilaton gravity which is originated from the low energy effective theory of type 0A string theory. We derive the correct Hawking temperature of the black holes including the effect of the back reaction of the radiation, and obtain the entropy by using the 1st law of black hole thermodynamics. For fixed-charge ensemble, the 0A black holes are free of phase transition and thermodynamically stable regardless of mass-charge ratio. We show this by interpreting the back reaction term as the inverse of the heat capacity of the black holes. Finally, the possibility of the phase transition in the fixed-potential ensemble is discussed.

Hongbin Kim

2011-07-22T23:59:59.000Z

445

Wave and quantum properties of peptide strings: defining a helix in spacetime  

E-Print Network [OSTI]

Previous studies have described the concept of peptide strings in qualitative terms and illustrated it by applying its corrolaries in order to elucidate basic questions in oncology and rheumatology. The present investigation is the first to quantify these potential sub- and transcellular phenomena. Accordingly, the propagation of peptide strings is proposed here to occur by way of waves that in turn are subject to the energy equation established by Planck. As a result of these insights, widespread future applications can now be envisaged for peptide strings both in molecular medicine and quantum optics.

Razvan Tudor Radulescu

2009-04-25T23:59:59.000Z

446

Mapping Kitaev's quantum double lattice models to Levin and Wen's string-net models  

E-Print Network [OSTI]

We exhibit a mapping identifying Kitaev's quantum double lattice models explicitly as a subclass of Levin and Wen's string net models via a completion of the local Hilbert spaces with auxiliary degrees of freedom. This identification allows to carry over to these string net models the representation-theoretic classification of the excitations in quantum double models, as well as define them in arbitrary lattices, and provides an illustration of the abstract notion of Morita equivalence. The possibility of generalising the map to broader classes of string nets is considered.

Oliver Buerschaper; Miguel Aguado

2009-10-29T23:59:59.000Z

447

Z2 electric strings and center vortices in SU(2) lattice gauge theory  

E-Print Network [OSTI]

We study the representations of SU(2) lattice gauge theory in terms of sums over the worldsheets of center vortices and Z2 electric strings, i.e. surfaces which open on the Wilson loop. It is shown that in contrast to center vortices the density of electric Z2 strings diverges in the continuum limit of the theory independently of the gauge fixing, however, their contribution to the Wilson loop yields physical string tension due to non-positivity of their statistical weight in the path integral, which is in turn related to the presence of Z2 topological monopoles in the theory.

M. I. Polikarpov; P. V. Buividovich

2008-01-01T23:59:59.000Z

448

On the Causal Structure of Spinning Einstein-Yang-Mills-Higgs Strings  

E-Print Network [OSTI]

It is claimed that it will be exceedingly unlikely to obtain CTC's in the spacetime of a spinning EYMH-string. It is conjectured that the pathological problems concerning the induced angular momentum and helical structure of time that afflict the U(1)-gauge string, will be solved in the non-abelian YM string model. In the pure YM case we find regular solutions, which resembles the abelian counterpart solutions but without causality violating regions. Just as in the spherical symmetric case, there will be probably critical behavior of the field equations at the threshold of blackhole masses.

Reinoud J. Slagter

1997-10-10T23:59:59.000Z

449

Entropy uncertainty relations and stability of phase-temporal quantum cryptography with finite-length transmitted strings  

SciTech Connect (OSTI)

Any key-generation session contains a finite number of quantum-state messages, and it is there-fore important to understand the fundamental restrictions imposed on the minimal length of a string required to obtain a secret key with a specified length. The entropy uncertainty relations for smooth min and max entropies considerably simplify and shorten the proof of security. A proof of security of quantum key distribution with phase-temporal encryption is presented. This protocol provides the maximum critical error compared to other protocols up to which secure key distribution is guaranteed. In addition, unlike other basic protocols (of the BB84 type), which are vulnerable with respect to an attack by 'blinding' of avalanche photodetectors, this protocol is stable with respect to such an attack and guarantees key security.

Molotkov, S. N., E-mail: sergei.molotkov@gmail.com [Russian Federation, Academy of Cryptography (Russian Federation)

2012-12-15T23:59:59.000Z

450

"Kerrr" black hole: the Lord of the String  

E-Print Network [OSTI]

Kerrr in the title is not a typo. The third "r" stands for "regular", in the sense of pathology-free, rotating black hole. We exhibit a long search-for, exact, Kerr-like, solution of the Einstein equations with novel features: i) no curvature ring singularity; ii) no "anti-gravity" universe with causality violating timelike closed world-lines; iii) no "super-luminal" matter disk. The ring singularity is replaced by a classical, circular, rotating string with Planck tension representing the inner engine driving the rotation of all the surrounding matter. The resulting geometry is regular and smoothly interpolates among inner Minkowski space, borderline deSitter and outer Kerr universe. The key ingredient to cure all unphysical features of the ordinary Kerr black hole is the choice of a "noncommutative geometry inspired" matter source as the input for the Einstein equations, in analogy with spherically symmetric black holes described in earlier works.

Smailagic, Anais

2010-01-01T23:59:59.000Z

451

Superconducting Cosmic Strings and One Dimensional Extended Supersymmetric Algebras  

E-Print Network [OSTI]

In this article we study in detail the supersymmetric structures that underlie the system of fermionic zero modes around a superconducting cosmic string. Particularly, we extend the analysis existing in the literature on the one dimensional $N=2$ supersymmetry and we find multiple $N=2$, $d=1$ supersymmetries. In addition, compact perturbations of the Witten index of the system are performed and we find to which physical situations these perturbations correspond. More importantly, we demonstrate that there exists a much more rich supersymmetric structure underlying the system of fermions with $N_f$ flavors and these are $N$-extended supersymmetric structures with non-trivial topological charges, with "$N$" depending on the fermion flavors.

V. K. Oikonomou

2014-04-30T23:59:59.000Z

452

Closed String Thermodynamics and a Blue Tensor Spectrum  

E-Print Network [OSTI]

The BICEP-2 team has reported the detection of primordial cosmic microwave background B-mode polarization, with hints of a suppression of power at large angular scales relative to smaller scales. Provided that the B-mode polarization is due to primordial gravitational waves, this might imply a blue tilt of the primordial gravitational wave spectrum. Such a tilt would be incompatible with standard inflationary models, although it was predicted some years ago in the context of a mechanism that thermally generates the primordial perturbations through a Hagedorn phase of string cosmology. The purpose of this note is to encourage greater scrutiny of the data with priors informed by a model that is immediately falsifiable, but which \\textit{predicts} features that might be favoured by the data-- namely a blue tensor tilt with an induced and complimentary red tilt to the scalar spectrum, with a naturally large tensor to scalar ratio that relates to both.

Robert H. Brandenberger; Ali Nayeri; Subodh P. Patil

2014-03-26T23:59:59.000Z

453

Cosmological and astrophysical constraints on superconducting cosmic strings  

SciTech Connect (OSTI)

We investigate the cosmological and astrophysical constraints on superconducting cosmic strings (SCSs). SCS loops emit strong bursts of electromagnetic waves, which might affect various cosmological and astrophysical observations. We take into account the effect on the CMB anisotropy, CMB blackbody spectrum, BBN, observational implications on radio wave burst and X-ray or ?-ray events, and stochastic gravitational wave background measured by pulsar timing experiments. We then derive constraints on the parameters of SCS from current observations and estimate prospects for detecting SCS signatures in on-going observations. As a result, we find that these constraints exclude broad parameter regions, and also that on-going radio wave observations can probe large parameter space.

Miyamoto, Koichi [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa 277-8582 (Japan); Nakayama, Kazunori, E-mail: miyamone@icrr.u-tokyo.ac.jp, E-mail: kazunori@hep-th.phys.s.u-tokyo.ac.jp [Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)

2013-07-01T23:59:59.000Z

454

Breaking the O(n 1/(2k-1) ) Barrier for InformationTheoretic Private Information Retrieval #  

E-Print Network [OSTI]

Information Retrieval (PIR) protocols allow a user to retrieve a data item from a database while hiding the identity of the item being retrieved. Specifically, in information­theoretic k­server PIR protocols of information­theoretic k­server PIR is improved to n O( log log k k log k ) . The new PIR protocols can also

Beimel, Amos

455

Monitored retrievable storage submission to Congress: Volume 2, Environmental assessment for a monitored retrievable storage facility. [Contains glossary  

SciTech Connect (OSTI)

This Environmental Assessment (EA) supports the DOE proposal to Congress to construct and operate a facility for monitored retrievable storage (MRS) of spent fuel at a site on the Clinch River in the Roane County portion of Oak Ridge, Tennessee. The first part of this document is an assessment of the value of, need for, and feasibility of an MRS facility as an integral component of the waste management system. The second part is an assessment and comparison of the potential environmental impacts projected for each of six site-design combinations. The MRS facility would be centrally located with respect to existing reactors, and would receive and canister spent fuel in preparation for shipment to and disposal in a geologic repository. 207 refs., 57 figs., 132 tabs.

none,

1986-02-01T23:59:59.000Z

456

Influence of sky radiance measurement errors on inversion-retrieved aerosol properties  

SciTech Connect (OSTI)

Remote sensing of the atmospheric aerosol is a well-established technique that is currently used for routine monitoring of this atmospheric component, both from ground-based and satellite. The AERONET program, initiated in the 90's, is the most extended network and the data provided are currently used by a wide community of users for aerosol characterization, satellite and model validation and synergetic use with other instrumentation (lidar, in-situ, etc.). Aerosol properties are derived within the network from measurements made by ground-based Sun-sky scanning radiometers. Sky radiances are acquired in two geometries: almucantar and principal plane. Discrepancies in the products obtained following both geometries have been observed and the main aim of this work is to determine if they could be justified by measurement errors. Three systematic errors have been analyzed in order to quantify the effects on the inversion-derived aerosol properties: calibration, pointing accuracy and finite field of view. Simulations have shown that typical uncertainty in the analyzed quantities (5% in calibration, 0.2 Degree-Sign in pointing and 1.2 Degree-Sign field of view) yields to errors in the retrieved parameters that vary depending on the aerosol type and geometry. While calibration and pointing errors have relevant impact on the products, the finite field of view does not produce notable differences.

Torres, B.; Toledano, C.; Cachorro, V. E.; Bennouna, Y. S.; Fuertes, D.; Gonzalez, R.; Frutos, A. M. de [Atmospheric Optics Group (GOA), University of Valladolid, Valladolid (Spain); Berjon, A. J. [Izana Atmospheric Research Center, Meteorological State Agency of Spain (AEMET), Sta. Cruz de Tenerife (Spain); Dubovik, O.; Goloub, P.; Podvin, T.; Blarel, L. [Laboratory of Atmospheric Optics, Universite Lille 1, Villeneuve d'Ascq (France)

2013-05-10T23:59:59.000Z

457

TIME-DEPENDENT SEARCHES FOR POINT SOURCES OF NEUTRINOS WITH THE 40-STRING AND 22-STRING CONFIGURATIONS OF ICECUBE  

SciTech Connect (OSTI)

This paper presents four searches for flaring sources of neutrinos using the IceCube neutrino telescope. For the first time, a search is performed over the entire parameter space of energy, direction, and time with sensitivity to neutrino flares lasting between 20 {mu}s and a year duration from astrophysical sources. Searches that integrate over time are less sensitive to flares because they are affected by a larger background of atmospheric neutrinos and muons that can be reduced by the use of additional timing information. Flaring sources considered here, such as active galactic nuclei, soft gamma-ray repeaters, and gamma-ray bursts, are promising candidate neutrino emitters. Two searches are 'untriggered' in the sense that they look for any possible flare in the entire sky and from a predefined catalog of sources from which photon flares have been recorded. The other two searches are triggered by multi-wavelength information on flares from blazars and from a soft gamma-ray repeater. One triggered search uses lightcurves from Fermi-LAT which provides continuous monitoring. A second triggered search uses information where the flux states have been measured only for short periods of time near the flares. The untriggered searches use data taken by 40 strings of IceCube between 2008 April 5 and 2009 May 20. The triggered searches also use data taken by the 22-string configuration of IceCube operating between 2007 May 31 and 2008 April 5. The results from all four searches are compatible with a fluctuation of the background.

Abbasi, R.; Aguilar, J. A.; Andeen, K.; Baker, M.; BenZvi, S. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Abdou, Y. [Department of Physics and Astronomy, University of Gent, B-9000 Gent (Belgium); Abu-Zayyad, T. [Department of Physics, University of Wisconsin, River Falls, WI 54022 (United States); Adams, J. [Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Ahlers, M. [Department of Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Auffenberg, J.; Becker, K.-H. [Department of Physics, University of Wuppertal, D-42119 Wuppertal (Germany); Bai, X. [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Barwick, S. W. [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Bay, R. [Department of Physics, University of California, Berkeley, CA 94720 (United States); Bazo Alba, J. L.; Benabderrahmane, M. L. [DESY, D-15735 Zeuthen (Germany); Beattie, K. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Beatty, J. J. [Department of Physics and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Bechet, S. [Universite Libre de Bruxelles, Science Faculty CP230, B-1050 Brussels (Belgium); Becker, J. K. [Fakultaet fuer Physik and Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Collaboration: IceCube Collaboration; and others

2012-01-01T23:59:59.000Z

458

Tools Developed to Prepare and Stabilize Reactor Spent Fuel for Retrieval from Tile Holes - 12251  

SciTech Connect (OSTI)

Spent fuel from the Chalk River Laboratories (CRL) nuclear reactors is stored in the waste management areas on site. This fuel is contained within carbon steel spent fuel cans that are stored inside vertical carbon steel lined concrete pipes in the ground known as tile holes. The fuel cans have been stored in the tile holes for greater than 30 years. Some of the fuel cans have experienced corrosion which may have affected their structural integrity as well as the potential to form hydrogen gas. In addition to these potential hazards, there was a need to clean contaminated surfaces inside of and around the exposed upper surface of the tile holes. As part of the site waste management remediation plan spent fuel will be retrieved from degraded tile holes, dried, and relocated to a new purpose built above ground storage facility. There have been a number of tools that are required to be developed to ensure spent fuel cans are in a safe condition prior to retrieval and re-location. A series of special purpose tools have been designed and constructed to stabilize the contents of the tile holes, to determine the integrity of the fuel containers and to decontaminate inside and around the tile holes. Described herein are the methods and types of tools used. Tools that have been presented here have been used, or will be used in the near future, in the waste management areas of the CRL Site in preparation for storage of spent fuel in a new above ground facility. The stabilization tools have been demonstrated on mock-up facilities prior to successful use in the field to remove hydrogen gas and uranium hydrides from the fuel cans. A lifting tool has been developed and used successfully in the field to confirm the integrity of the fuel cans for future relocation. A tool using a commercial dry ice blaster has been developed and is ready to start mock-up trials and is scheduled to be used in the field during the summer of 2012. (authors)

Horne, Michael; Clough, Malcolm [Atomic Energy of Canada Limited (Canada)

2012-07-01T23:59:59.000Z

459

First LIGO search for gravitational wave bursts from cosmic (super)strings  

E-Print Network [OSTI]

We report on a matched-filter search for gravitational wave bursts from cosmic string cusps using LIGO data from the fourth science run (S4) which took place in February and March 2005. No gravitational waves were detected ...

Zucker, Michael E.

460

Constraints on Cosmic Strings from the LIGO-Virgo Gravitational-Wave Detectors  

E-Print Network [OSTI]

Cosmic strings can give rise to a large variety of interesting astrophysical phenomena. Among them, powerful bursts of gravitational waves (GWs) produced by cusps are a promising observational signature. In this Letter we ...

Aggarwal, Nancy

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

EM-31 RETRIEVAL KNOWLEDGE CENTER MEETING REPORT: MOBILIZE AND DISLODGE TANK WASTE HEELS  

SciTech Connect (OSTI)

The Retrieval Knowledge Center sponsored a meeting in June 2009 to review challenges and gaps to retrieval of tank waste heels. The facilitated meeting was held at the Savannah River Research Campus with personnel broadly representing tank waste retrieval knowledge at Hanford, Savannah River, Idaho, and Oak Ridge. This document captures the results of this meeting. In summary, it was agreed that the challenges to retrieval of tank waste heels fell into two broad categories: (1) mechanical heel waste retrieval methodologies and equipment and (2) understanding and manipulating the heel waste (physical, radiological, and chemical characteristics) to support retrieval options and subsequent processing. Recent successes and lessons from deployments of the Sand and Salt Mantis vehicles as well as retrieval of C-Area tanks at Hanford were reviewed. Suggestions to address existing retrieval approaches that utilize a limited set of tools and techniques are included in this report. The meeting found that there had been very little effort to improve or integrate the multiple proven or new techniques and tools available into a menu of available methods for rapid insertion into baselines. It is recommended that focused developmental efforts continue in the two areas underway (low-level mixing evaluation and pumping slurries with large solid materials) and that projects to demonstrate new/improved tools be launched to outfit tank farm operators with the needed tools to complete tank heel retrievals effectively and efficiently. This document describes the results of a meeting held on June 3, 2009 at the Savannah River Site in South Carolina to identify technology gaps and potential technology solutions to retrieving high-level waste (HLW) heels from waste tanks within the complex of sites run by the U. S. Department of Energy (DOE). The meeting brought together personnel with extensive tank waste retrieval knowledge from DOE's four major waste sites - Hanford, Savannah River, Idaho, and Oak Ridge. The meeting was arranged by the Retrieval Knowledge Center (RKC), which is a technology development project sponsored by the Office of Technology Innovation & Development - formerly the Office of Engineering and Technology - within the DOE Office of Environmental Management (EM).

Fellinger, A.

2010-02-16T23:59:59.000Z

462

Functional design criteria, Project W-211, Initial Tank Retrieval Systems. Revision 1  

SciTech Connect (OSTI)

This document provides the technical baseline for retrieval of waste from ten double-shell tanks in the SY, AN, AP, AW, AY, and AZ tank farms. In order to retrieve waste from these tanks, systems are needed to mix the sludge with the supernate and pump the waste mixture from the tank. For 101-SY, the existing mitigation pump will be used to mix the waste and Project W-211 will provide for waste removal. The retrieval scope for the other nine tanks includes both the waste mixing and removal functions.

Rieck, C.A.

1995-02-07T23:59:59.000Z

463

Virtual edge illumination and one dimensional beam tracking for absorption, refraction, and scattering retrieval  

SciTech Connect (OSTI)

We propose two different approaches to retrieve x-ray absorption, refraction, and scattering signals using a one dimensional scan and a high resolution detector. The first method can be easily implemented in existing procedures developed for edge illumination to retrieve absorption and refraction signals, giving comparable image quality while reducing exposure time and delivered dose. The second method tracks the variations of the beam intensity profile on the detector through a multi-Gaussian interpolation, allowing the additional retrieval of the scattering signal.

Vittoria, Fabio A., E-mail: fabio.vittoria.12@ucl.ac.uk; Diemoz, Paul C. [Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower Street, London WC1E 6BT (United Kingdom); Research Complex at Harwell, Harwell Oxford Campus, OX11 0FA Didcot (United Kingdom); Endrizzi, Marco; Olivo, Alessandro [Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower Street, London WC1E 6BT (United Kingdom); Wagner, Ulrich H.; Rau, Christoph [Diamond Light Source, Harwell Oxford Campus, OX11 0DE Didcot (United Kingdom); Robinson, Ian K. [Research Complex at Harwell, Harwell Oxford Campus, OX11 0FA Didcot (United Kingdom); London Centre for Nanotechnology, WC1H 0AH London (United Kingdom)

2014-03-31T23:59:59.000Z

464

Global vs local cosmic strings from pseudo-anomalous U(1)  

E-Print Network [OSTI]

We study the structure of cosmic strings produced at the breaking of an anomalous U(1) gauge symmetry present in many superstring compactification models. We show that their coupling with the axion necessary in order to cancel the anomalies does not prevent them from being local, even though their energy per unit length is found to diverge logarithmically. We discuss the formation of such strings and the phenomenological constraints that apply to their parameters.

Binétruy, Pierre; Peter, P

1998-01-01T23:59:59.000Z

465

Methods and systems for determining angular orientation of a drill string  

DOE Patents [OSTI]

Preferred methods and systems generate a control input based on a periodically-varying characteristic associated with the rotation of a drill string. The periodically varying characteristic can be correlated with the magnetic tool face and gravity tool face of a rotating component of the drill string, so that the control input can be used to initiate a response in the rotating component as a function of gravity tool face.

Cobern, Martin E. (Cheshire, CT)

2010-03-23T23:59:59.000Z

466

Can a self-gravitating thin cosmic string obey the Nambu-Goto dynamics ?  

E-Print Network [OSTI]

We assume that a self-gravitating string is locally described by a thin tube of matter represented by a ``smoothed conical metric''. If we impose a specific constraint on the model of string then its central line obeys the Nambu-Goto dynamics in the limit where the radius of the tube tends to zero. If no constraint is added then the world sheet of the central line is totally geodesic.

B. Boisseau; C. Charmousis; B. Linet

1997-10-14T23:59:59.000Z

467

Re-evaluation of monitored retrievable storage concepts  

SciTech Connect (OSTI)

In 1983, as a prelude to the monitored retrievable storage (MRS) facility conceptual design, the Pacific Northwest Laboratory (PNL) conducted an evaluation for the US Department of Energy (DOE) that examined alternative concepts for storing spent LWR fuel and high- level wastes from fuel reprocessing. The evaluation was made considering nine concepts for dry away-from-reactor storage. The nine concepts evaluated were: concrete storage cask, tunnel drywell, concrete cask-in-trench, open-cycle vault, metal casks (transportable and stationary), closed-cycle vault, field drywell, and tunnel-rack vault. The purpose and scope of the re-evaluation did not require a repetition of the expert-based examinations used earlier. Instead, it was based on more detailed technical review by a small group, focusing on changes that had occurred since the initial evaluation was made. Two additional storage concepts--the water pool and the horizontal modular storage vault (NUHOMS system)--were ranked along with the original nine. The original nine concepts and the added two conceptual designs were modified as appropriate for a scenario with storage capacity for 15,000 MTU of spent fuel. Costs, area requirements, and technical and historical data pertaining to MRS storage were updated for each concept.

Fletcher, J.F.; Smith, R.I.

1989-04-01T23:59:59.000Z

468

Mapping the development in Information Retrieval specialty: A bibliometric analysis via journals  

E-Print Network [OSTI]

and their changes over time by using journal cocitation analysis during the period of 1987-1997. Data are retrieved and referring to the same scientific literature (Price 1965). Researchers within a specialty communicate more

Menczer, Filippo

469

Potential for criticality in Hanford tanks resulting from retrieval of tank waste  

SciTech Connect (OSTI)

This report assesses the potential during retrieval operations for segregation and concentration of fissile material to result in a criticality. The sluicing retrieval of C-106 sludge to AY-102 and the operation of mixer pumps in SY-102 are examined in some detail. These two tanks (C-106, SY-102) were selected because of the near term plans for retrieval of these tanks and their high plutonium inventories relative to other tanks. Although all underground storage tanks are subcritical by a wide margin if assumed to be uniform in composition, the possibility retrieval operations could preferentially segregate the plutonium and locally concentrate it sufficiently to result in criticality was a concern. This report examines the potential for this segregation to occur.

Whyatt, G.A.; Sterne, R.J.; Mattigod, S.V. [and others

1996-09-01T23:59:59.000Z

470

E-Print Network 3.0 - abundance retrieval method Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Page: << < 1 2 3 4 5 > >> Page: << < 1 2 3 4 5 > >> 81 Retrieval of ozone and nitrogen dioxide concentrations from Stratospheric Aerosol and Gas Experiment III (SAGE III)...

471

Retrieval of cloud-cleared atmospheric temperature profiles from hyperspectral infrared and microwave observations  

E-Print Network [OSTI]

This thesis addresses the problem of retrieving the temperature profile of the Earth's atmosphere from overhead infrared and microwave observations of spectral radiance in cloudy conditions. The contributions of the thesis ...

Blackwell, William Joseph, 1971-

2002-01-01T23:59:59.000Z

472

Use of airs and modis thermal infrared channels to retrieve ice cloud properties  

E-Print Network [OSTI]

In this study, we use thermal infrared channels to retrieve the optical thickness and effective particle radius of ice clouds. A physical model is used in conjunction with Atmospheric Infrared Sounder (AIRS) temperature and water vapor profiles...

Yost, Christopher Rogers

2007-04-25T23:59:59.000Z

473

Removal Action Plan for the Accelerated Retrieval Project for a Described Area within Pit 4  

SciTech Connect (OSTI)

This Removal Action Plan documents the plan for implementation of the Comprehensive Environmental Response, Compenstion, and Liability Act non-time-critical removal action to be performed by the Accelerated Retrieval Project. The focus of the action is the limited excavation and retrieval of selected waste streams from a designated portion of the Radioactive Waste Management Complex Subsurface Disposal Area that are contaminated with volatile organic compounds, isotopes of uranium, or transuranic radionuclides. The selected retrieval area is approximately 0.2 ha (1/2 acre) and is located in the eastern portion of Pit 4. The proposed project is referred to as the Accelerated Retrieval Project. This Removal Action Plan details the major work elements, operations approach, and schedule, and summarizes the environmental, safety and health, and waste management considerations associated with the project.

A. M. Tyson

2006-08-01T23:59:59.000Z

474

Global precipitation retrieval algorithm trained for SSMIS using a numerical weather prediction model: Design and evaluation  

E-Print Network [OSTI]

This paper presents and evaluates a global precipitation retrieval algorithm for the Special Sensor Microwave Imager/Sounder (SSMIS). It is based on those developed earlier for the Advanced Microwave Sounding Unit (AMSU) ...

Surussavadee, Chinnawat

475

Study of cloud properties from single-scattering, radiative forcing, and retrieval perspectives  

E-Print Network [OSTI]

This dissertation reports on three different yet related topics in light scattering computation, radiative transfer simulation, and remote sensing implementation, regarding the cloud properties and the retrieval of cloud properties from satellite...

Lee, Yong-Keun

2009-06-02T23:59:59.000Z

476

Advancements in scientific data searching, sharing and retrieval Ranjeet Devarakonda1  

E-Print Network [OSTI]

Advancements in scientific data searching, sharing and retrieval Ranjeet Devarakonda1 , Giri including metadata management,indexing, searching, data sharing, and alsosoftware reusability. Mercurysystem are indexed against Solr iii search API consistently, so thatit can rendervarious search capabilities

477

Cognitive and neural correlates of memory retrieval in young and older adults  

E-Print Network [OSTI]

(cont.) increased activity whenever recollection was attempted, independent of the level of recollection success. The results are consistent with the hypothesis that increased left-lateralized retrieval activity in older ...

O'Kane, Gail, 1965-

2004-01-01T23:59:59.000Z

478

Functions and requirements for 105-KE Basin sludge retrieval and packaging  

SciTech Connect (OSTI)

Sludge, and the clouding due to sludge, interferes with basin operation and maintenance activities. This document defines the overall functions and requirements for sludge retrieval and packaging activities to be performed in the 105-KE Basin.

Feigenbutz, L.V.

1994-12-16T23:59:59.000Z

479

Project Execution Plan for Project W-211 Initial Tank Retrieval Systems (ITRS)  

SciTech Connect (OSTI)

This Project Execution Plan documents the methodology for managing Project W-211. Project W-211, Initial Tank Retrieval Systems (ITRS), is a fiscal year 1994 Major Systems Acquisition that will provide systems for retrieval of radioactive wastes from selected double-shell tanks (DST). The contents of these tanks are a combination of supernatant liquids and settled solids. To retrieve waste from the tanks, it is first necessary to mix the liquid and solids prior to transferring the slurry to alternative storage or treatment facilities. The ITRS will provide systems to mobilize the settled solids and transfer the wastes out of the tanks. In so doing, ITRS provides feed for the future waste treatment plant, allows for consolidation of tank solids to manage space within existing DST storage capacity, and supports continued safe storage of tank waste. The ITRS scope has been revised to include waste retrieval systems for tanks AP-102, AP-104, AN-102, AN-103, AN-104, AN-105, AY-102, AZ-102, and SY-102. This current tank selection and sequence provides retrieval systems supporting the River Protection Project (RF'P) Waste Treatment Facility and sustains the ability to provide final remediation of several watch list DSTs via treatment. The ITRS is configured to support changing program needs, as constrained by available budget, by maintaining the flexibility for exchanging tanks requiring mixer pump-based retrieval systems and shifting the retrieval sequence. Preliminary design was configured such that an adequate basis exists for initiating Title II design of a mixer pump-based retrieval system for any DST. This Project Execution Plan (PEP), derived from the predecessor Project Management Plan, documents the methodology for managing the ITRS, formalizes organizational responsibilities and interfaces, and identifies project requirements such as change control, design verification, systems engineering, and human factors engineering.

VAN BEEK, J.E.

2000-04-19T23:59:59.000Z

480

Project Execution Plan for Project W-211 Initial Tank Retrieval Systems (ITRS)  

SciTech Connect (OSTI)

Project W-211, Initial Tank Retrieval Systems (ITRS), is a fiscal year 1994 Major Systems Acquisition that will provide systems for retrieval of radioactive wastes from selected double-shell tanks (DST). The contents of these tanks are a combination of supernatant liquids and settled solids. To retrieve waste from the tanks, it is first necessary to mix the liquid and solids prior to transferring the slurry to alternative storage or treatment facilities. The ITRS will provide systems to mobilize the settled solids and transfer the wastes out of the tanks. In so doing, ITRS provides feed for future processing plants, allows for consolidation of tank solids to manage space within existing DST storage capacity, and supports continued safe storage of tank waste. The ITRS scope has been revised to include waste retrieval systems for tanks AP-102, AP-104, AP-108, AN-103, AN-104, AN-105, AY-102, AZ-102, and SY-102. This current tank selection and sequence provides retrieval systems supporting the Privatized waste processing plant and sustains the ability to provide final remediation of several watch list DSTs via treatment. The ITRS is configured to support changing program needs, as constrained by available budget, by maintaining the flexibility for exchanging tanks requiring mixer pump-based retrieval systems and shifting the retrieval sequence. Preliminary design was configured such that an adequate basis exists for initiating Title II design of a mixer pump based retrieval system for any DST. This Project Management Plan (PMP) documents the methodology for managing the ITRS, formalizes organizational responsibilities and interfaces, and identifies project requirements such as change control, design verification, systems engineering, and human factors engineering.

VAN BEEK, J.E.

1999-09-02T23:59:59.000Z

Note: This page contains sample records for the topic "type string retrieved" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Cloud shading retrieval and assimilation in a satellite-model coupled mesoscale analysis system  

SciTech Connect (OSTI)

A retrieval-assimilation method has been developed as a quantitative means to exploit the information in satellite imagery regarding shading of the ground by clouds, as applied to mesoscale weather analysis. Cloud radiative parameters are retrieved from satellite visible image data and used, along with parameters computed by a numerical model, to control the model's computation of downward radiative fluxes at the ground. These fluxes influence the analysis of ground surface temperatures under clouds. The method is part of a satellite-model coupled four-dimensional analysis system that merges information from visible image data in cloudy areas with infrared sounder data in clear areas, where retrievals of surface temperatures and water vapor concentrations are assimilated. The substantial impact of shading on boundary-layer development and mesoscale circulations was demonstrated in simulations, and the value of assimilating shading retrievals was demonstrated with a case study and with a simulated analysis that included the effects of several potential sources of error. The case study was performed in the northwestern Texas area, where convective cloud development was influenced by the shading effects of a persistent region of stratiform cloud cover. Analyses that included shading retrieval assimilation had consistently smaller shelter-height temperature errors than analyses without shading retrievals. When clear-area surface temperature retrievals from sounder data were analyzed along with cloudy-area shading retrievals, the contrast in heating between the shaded and clear parts of the domain led to large variations in analyzed boundary-layer depths and had a modest impact on analyzed wind flow. The analyzed locations of upward vertical motion corresponded roughly to areas of convective cloud development observed in satellite imagery. 29 refs., 17 figs., 2 tabs.

Lipton, A.E. (Phillips Lab., Hanscom AFB, MA (United States))

1993-11-01T23:59:59.000Z

482

Feasibility study: Assess the feasibility of siting a monitored retrievable storage facility. Phase 1  

SciTech Connect (OSTI)

The purpose of phase one of this study are: To understand the waste management system and a monitored retrievable storage facility; and to determine whether the applicant has real interest in pursuing the feasibility assessment process. Contents of this report are: Generating electric power; facts about exposure to radiation; handling storage, and transportation techniques; description of a proposed monitored retrievable storage facility; and benefits to be received by host jurisdiction.

King, J.W.

1993-08-01T23:59:59.000Z

483

Signals of Inflation in a Friendly String Landscape  

E-Print Network [OSTI]

Following Freivogel {\\it et al} we consider inflation in a predictive (or `friendly') region of the landscape of string vacua, as modeled by Arkani-Hamed, Dimopoulos and Kachru. In such a region the dimensionful coefficients of super-renormalizable operators unprotected by symmetries, such as the vacuum energy and scalar mass-squareds are freely scanned over, and the objects of study are anthropically or `environmentally' conditioned probability distributions for observables. In this context we study the statistical predictions of (inverted) hybrid inflation models, where the properties of the inflaton are probabilistically distributed. We derive the resulting distributions of observables, including the deviation from flatness $|1-\\Omega|$, the spectral index of scalar cosmological perturbations $n_s$ (and its scale dependence $dn_s/d\\log k$), and the ratio of tensor to scalar perturbations $r$. The environmental bound on the curvature implies a solution to the $\\eta$-problem of inflation with the predicted distribution of $(1-n_s)$ indicating values close to current observations. We find a relatively low probability ($<3%$) of `just-so' inflation with measurable deviations from flatness. Intermediate scales of inflation are preferred in these models.

John March-Russell; Francesco Riva

2006-04-11T23:59:59.000Z

484

Acceleration of electric current-carrying string loop near a Schwarzschild black hole immersed in an asymptotically uniform magnetic field  

E-Print Network [OSTI]

We study the acceleration of an electric current-carrying and axially-symmetric string loop initially oscillating in the vicinity of a Schwarzschild black hole embedded in an external asymptotically uniform magnetic field. The plane of the string loop is orthogonal to the magnetic field lines and the acceleration of the string loop occurs due to the transmutation effect turning in the deep gravitational field the internal energy of the oscillating strings to the energy of their translational motion along the axis given by the symmetry of the black hole spacetime and the magnetic field. We restrict our attention to the motion of string loop with energy high enough, when it can overcome the gravitational attraction and escape to infinity. We demonstrate that for the current-carrying string loop the transmutation effect is enhanced by the contribution of the interaction between the electric current of the string loop and the external magnetic field and we give conditions that have to be fulfilled for an efficient acceleration. The Schwarzschild black hole combined with the strong external magnetic field can accelerate the current-carrying string loop up to the velocities close to the speed of light $v \\sim c$. Therefore, the string loop transmutation effect can potentially well serve as an explanation for acceleration of highly relativistic jets observed in microquasars and active galactic nuclei.

Arman Tursunov; Martin Kološ; Zden?k Stuchlík; Bobomurat Ahmedov

2014-09-18T23:59:59.000Z

485

Retrieval of Cloud Phase and Ice Crystal Habit from Satellite Data  

SciTech Connect (OSTI)

Knowledge of cloud phase (liquid or ice) and crystal habit are of fundamental importance to both remote sensing and climate simulations. Using water droplets instead of ice crystals in retrieving cloud properties from satellite data can lead to errors in the retrieval of cloud height, optical thickness, and microphysical properties. Satellite retrievals of microphysical properties are also influenced by the crystal habit used in the retrieval, either indirectly via an assumed phase function or directly via assumed profiles of ice crystal habits. Realistic treatment of ice cloud radiative and microphysical properties, which depend on crystal habit, is important in climate simulations, especially in tropical anvil regions. In this work, we present a method for retrieving cloud phase and the dominant ice crystal habit from radiances measured by the Multi-angle Imaging Spectro-Radiometer (MISR) and the Moderate Resolution Imaging Spectroradiometer (MODIS). The shape of an atmospheric particle affects the scattering of light such that water droplets and ice crystals of various habits have somewhat different phase functions. Consequently the radiances measured by the MISR instrument, which observes light scattered from the same cloud at nine different viewing angles, are functions of the crystal shape. In principle, the measured angular radiance pattern can be used to infer the crystal shape. In this work, we present initial results from a cloud phase and ice crystal habit retrieval based on combining the MISR multi-angular visible wavelength measurements with MODIS shortwave infrared measurements. The nine angular measurements provided by the MISR cameras allow a wide range of scattering angles to be viewed in a single scene, which provides sensitivity to particle habit. The presence of the MODIS instrument on the same satellite allows additional information on particle size to be incorporated into the retrievals. Results of the retrieval method are presented for several case studies over the continental United States. Cloud phase can be determined from the MISR angular measurements alone, due to the large differences in the phase functions of water droplets and ice crystals. By combining the MISR and MODIS measurements, crystal habit, effective radius, and optical depth can be inferred simultaneously for ice clouds. Comparisons with ground-based retrieval methods and semi-coincident in situ data illustrate that the retrieved crystal habits and sizes are reasonable.

McFarlane, Sally A.; Marchand, Roger T.; Ackerman, Thomas P.

2004-07-19T23:59:59.000Z

486

Gravitational Kaluza-Klein modes in the String-Cigar Braneworld  

E-Print Network [OSTI]

In this work the gravitational Kaluza-Klein (KK) modes are analysed on string-like braneworlds in six dimensions, namely the thin string-like Gherghetta-Shaposhnikov (GS) and the thick string-cigar model. We find a new massless mode in both modes satisfying the respective Schroedinger equation. By means of numerical analysis for both models, a complete graviton spectrum and eigenfunctions is attained. Besides the linear regime, the KK spectrum exhibits a decreasing behavior with an asymmetric mass gap with respect to the massless mode. The discontinuity is bigger in the GS model, and it is invariant upon the geometrical flow. A massive mode is obtained in the GS model with a tiny mass which does not match in any regime. It turns out that in the string-cigar model, the core brane structure smoothes and amplifies the KK modes near the brane. Further, the presence of a potential well allows the existence of resonant massive gravitons for small masses in the string-cigar scenario.

D. F. S. Veras; J. E. G. Silva; W. T. Cruz; C. A. S. Almeida

2014-09-10T23:59:59.000Z

487

Field performance of the waste retrieval end effectors in the Oak Ridge gunite tanks  

SciTech Connect (OSTI)

Waterjet-based tank waste retrieval end effectors have been developed by Retrieval Process Development and Enhancements through several generations of test articles targeted at deployment in Hanford underground storage tanks with a large robotic arm. The basic technology has demonstrated effectiveness for retrieval of simulants bounding a wide range of waste properties and compatibility with foreseen deployment systems. The Oak Ridge National Laboratory (ORNL) selected the waterjet scarifying end effector, the jet pump conveyance system, and the Modified Light Duty Utility Arm and Houdini Remotely Operated Vehicle deployment and manipulator systems for evaluation in the Gunite and Associated Tanks Treatability Study (GAAT-TS). The Retrieval Process Development and Enhancements (RPD&E) team was tasked with developing a version of the retrieval end effector tailored to the Oak Ridge tanks, waste, and deployment platforms. The conceptual design was done by the University of Missouri-Rolla in FY 1995-96. The university researchers conducted separate effects tests of the component concepts, scaled the basic design features, and constructed a full-scale test article incorporating their findings in early FY 1996. The test article was extensively evaluated in the Hanford Hydraulic Testbed and the design features were further refined. Detail design of the prototype item was started at Waterjet Technology, Inc. before the development testing was finished, and two of the three main subassemblies were substantially complete before final design of the waterjet manifold was determined from the Hanford hydraulic testbed (HTB) testing. The manifold on the first prototype was optimized for sludge retrieval; assembled with that manifold, the end effector is termed the Sludge Retrieval End Effector (SREE).

Mullen, O.D.

1997-09-01T23:59:59.000Z

488

Classification of $SU(4) \\times SU(2) \\times U(1)$ Heterotic-String Models  

E-Print Network [OSTI]

The free fermionic construction of the heterotic string in four dimensions produced a large space of three generation models with the underlying $SO(10)$ embedding of the Standard Model states. The $SO(10)$ symmetry is broken to a subgroup directly at the string scale. Over the past few years free fermionic models with the Pati-Salam and flipped $SU(5)$ subgroups have been classified. In this paper we extend this classification program to models in which the $SO(10)$ symmetry is broken at the string level to the $SU(4)\\times SU(2)_L\\times U(1)_R$ (SU421) subgroup. The subspace of free fermionic models that we consider corresponds to symmetric ${\\mathbb{Z}}_2 \\times {\\mathbb{Z}}_2$ orbifolds. We provide a general argument that shows that this class of SU421 free fermionic models cannot produce viable three generation models.

Alon E. Faraggi; Hasan Sonmez

2014-12-09T23:59:59.000Z

489

A Statistic for identifying cosmic string wakes and other sheet-like structure  

E-Print Network [OSTI]

We describe an implementation of the structure functions of Babul \\& Starkman, in order to quantify the ``sheet-like'' nature of a distribution of matter. We test this statistic on a toy model describing cosmic string wakes, and show that it does a better job than other statistics which have been proposed for distinguishing non-Gaussianity in the form of sheets. We conclude that the most favoured cosmic string model is unlikely to produce a significant increase in the sheet-like nature of the matter distribution beyond that which occurs in Gaussian models (with the same power spectrum) due to the formation of Zeldovich pancakes. Although the statistic was developed in the context of cosmic string wake formation, we expect it to be useful for comparing the observed galaxy distribution with a wide range of theoretical models with different power spectra.

James Robinson; Andreas Albrecht

1996-02-26T23:59:59.000Z

490

Holographic light quark jet quenching at RHIC and LHC via the shooting strings  

E-Print Network [OSTI]

A new shooting string holographic model of jet quenching of light quarks in strongly coupled plasmas is presented to overcome the phenomenological incompatibilities of previous falling string holographic scenarios that emerged when confronted with the recent LHC data. This model is based on strings with finite momentum endpoints that start close to the horizon and lose energy as they approach the boundary. This framework is applied to compute the nuclear modification factor RAA of light hadrons at RHIC and LHC, showing that this model improves greatly the comparison with the recent light hadron suppression data. The effects of the Gauss-Bonnet quadratic curvature corrections to the AdS5 geometry further improve the agreement with the data.

Andrej Ficnar; Steven S. Gubser; Miklos Gyulassy

2014-04-03T23:59:59.000Z

491

The Landscape of String Theory and The Wave Function of the Universe  

E-Print Network [OSTI]

We explore the possibility that quantum cosmology considerations could provide a selection principle in the landscape of string vacua. We propose that the universe emerged from the string era in a thermally excited state and determine, within a mini-superspace model, the probability of tunneling to different points on the landscape. We find that the potential energy of the tunneling end point from which the universe emerges and begins its classical evolution is determined by the primordial temperature. By taking into account some generic properties of the moduli potential we then argue that the tunneling to the tail of the moduli potentials is disfavored, that the most likely emergence point is near an extremum, and that this extremum is not likely to be in the outer region of moduli space where the compact volume is very large and the string coupling very weak. As a concrete example we discuss the application of our arguments to the KKLT model of moduli stabilization.

R. Brustein; S. P. de Alwis

2005-11-24T23:59:59.000Z

492

High Redshift Gamma-Ray Bursts: Observational Signatures of Superconducting Cosmic Strings?  

E-Print Network [OSTI]

The high-redshift gamma-ray bursts (GRBs), GRBs 080913 and 090423, challenge the conventional GRB progenitor models by their short durations, typical for short GRBs, and their high energy releases, typical for long GRBs. Meanwhile, the GRB rate inferred from high-redshift GRBs also remarkably exceeds the prediction of the collapsar model, with an ordinary star formation history. We show that all these contradictions could be eliminated naturally, if we ascribe some high-redshift GRBs to electromagnetic bursts of superconducting cosmic strings. High-redshift GRBs could become a reasonable way to test the superconducting cosmic string model, because the event rate of cosmic string bursts increases rapidly with increasing redshifts, whereas the collapsar rate decreases.

K. S. Cheng; Yun-Wei Yu; T. Harko

2010-06-11T23:59:59.000Z

493

Retrieval of Cloud Phase and Crystal Habit from Multiangle Imaging Spectroradiometer (MISR) and Moderate Resolution Imaging Spectroradiometer (MODIS) Data  

SciTech Connect (OSTI)

A method of retrieving cloud phase and the dominant ice crystal habit from radiances measured by the Multi-angle Imaging Spectro-Radiometer (MISR) and the Moderate Resolution Imaging Spectroradiometer (MODIS) has been developed. The retrieval method takes advantage of the differences in the phase function of various particle shapes as a function of scattering angle. Three case studies are presented which illustrate the retrieval method. A comparison with semi-coincident in situ observations for one case study indicates that the retrieved crystal habits are consistent with the observations.

McFarlane, Sally A.; Marchand, Roger T.; Ackerman, Thomas P.

2005-07-22T23:59:59.000Z

494

Performance benefits of telerobotics and teleoperation - enhancements for an arm-based tank waste retrieval system  

SciTech Connect (OSTI)

This report evaluates telerobotic and teleoperational arm-based retrieval systems that require advanced robotic controls. These systems will be deployed in waste retrieval activities in Hanford`s Single Shell Tanks (SSTs). The report assumes that arm-based, retrieval systems will combine a teleoperational arm and control system enhanced by a number of advanced and telerobotic controls. The report describes many possible enhancements, spanning the full range of the control spectrum with the potential for technical maturation. The enhancements considered present a variety of choices and factors including: the enhancements to be included in the actual control system, safety, detailed task analyses, human factors, cost-benefit ratios, and availability and maturity of technology. Because the actual system will be designed by an offsite vendor, the procurement specifications must have the flexibility to allow bidders to propose a broad range of ideas, yet build in enough restrictions to filter out infeasible and undesirable approaches. At the same time they must allow selection of a technically promising proposal. Based on a preliminary analysis of the waste retrieval task, and considering factors such as operator limitations and the current state of robotics technology, the authors recommend a set of enhancements that will (1) allow the system to complete its waste retrieval mission, and (2) enable future upgrades in response to changing mission needs and technological advances.

Horschel, D.S. [Sandia National Labs., Albuquerque, NM (United States); Gibbons, P.W. [Westinghouse Hanford Co., Richland, WA (United States); Draper, J.V. [Oak Ridge National Lab., TN (United States)] [and others

1995-06-01T23:59:59.000Z

495

Innovative systems for mixed waste retrieval and/or treatment in confined spaces  

SciTech Connect (OSTI)

Fernald established operations in 1951 and produced uranium and other metals for use at other DOE facilities. A part of the sitewide remediation effort is the removal, treatment, and disposal of the K-65 wastes from Silos 1 and 2. These silos contain radium-bearing residues from the processing of pitchblende ore. An Engineering Evaluation/Cost Analysis was prepared to evaluate the removal action alternatives using the preliminary characterization data and select a preferred alternative. The selected alternative consisted of covering the K-65 residues and the silo dome. The remediation of the K-65 wastes consists of the retrieval and treatment of the wastes prior to final disposal, which has not yet been determined. Treatment will be performed in a new facility to be built adjacent to the silos. The wastes must be retrieved from silos in an efficient and reliable way and delivered to the treatment facility. The first challenge of covering the wastes with bentonite has been successfully met. The second phase of retrieving the wastes from the silos is not due for a few years. However, conceptual design and configuration of the retrieval system have been developed as part of the Conceptual Design Report. The system is based on the utilization of hydraulic mining techniques, and is based on similar successful applications. This report describes the emplacement of the bentonite grant and the design for the slurry retrieval system.

Fekete, L.J.; Ghusn, A.E. [Parsons Environmental Services, Inc., Fairfield, OH (United States)

1993-03-01T23:59:59.000Z

496

Review Guidance for the TWRS FSAR amendment for Waste Retrieval and waste feed delivery  

SciTech Connect (OSTI)

This review guidance (Guide) was developed for Office of River Protection (ORP) reviewers to use in reviewing the amendment to the Tank Waste Remediation System (TWRS) Final Safety Analysis Report (FSAR) covering waste retrieval and waste feed delivery. Waste retrieval and waste feed delivery are necessary to supply nuclear waste from TWRS storage tanks to the TWRS Privatization (TWRS-P) Contractor's vitrification facility and to receive intermediate waste from the vitrification facility back into the TWRS tank farms for interim storage. An amendment to the approved TWRS FSAR (HNF-SD-WM-SAR-067, Rev. 0) is necessary to change the authorization basis to accommodate waste retrieval and waste feed delivery. The ORP'S safety responsibility in reviewing the FSAR amendment is to determine that reasonable assurance exists that waste retrieval and waste feed delivery operations can be accomplished with adequate safety for the workers, the public, and the environment. To carry out this responsibility, the ORP will evaluate the Contractor's amendment to the TWRS FSAR for waste retrieval and waste feed delivery to determine whether the submittal provides adequate safety and complies with applicable regulatory requirements.

GRIFFITH, R.W.

1999-10-01T23:59:59.000Z

497

New Technique for Retrieving Liquid Water Path over Land using Satellite Microwave Observations  

SciTech Connect (OSTI)

We present a new methodology for retrieving liquid water path over land using satellite microwave observations. As input, the technique exploits the Advanced Microwave Scanning Radiometer for earth observing plan (EOS) (AMSR-E) polarization-difference signals at 37 and 89 GHz. Regression analysis performed on model simulations indicates that over variable atmospheric and surface conditions the polarization-difference signals can be simply parameterized in terms of the surface emissivity polarization difference ({Delta}{var_epsilon}), surface temperature, liquid water path (LWP), and precipitable water vapor (PWV). The resulting polarization-difference parameterization (PDP) enables fast and direct (noniterative) retrievals of LWP with minimal requirements for ancillary data. Single- and dual-channel retrieval methods are described and demonstrated. Data gridding is used to reduce the effects of instrumental noise. The methodology is demonstrated using AMSR-E observations over the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site during a six day period in November and December, 2003. Single- and dual-channel retrieval results mostly agree with ground-based microwave retrievals of LWP to within approximately 0.04 mm.

Deeter, M.N.; Vivekanandan, J.

2005-03-18T23:59:59.000Z

498

String loops in the field of braneworld spherically symmetric black holes and naked singularities  

SciTech Connect (OSTI)

We study motion of current-carrying string loops in the field of braneworld spherically symmetric black holes and naked singularities. The spacetime is described by the Reissner-Nordström geometry with tidal charge b reflecting the non-local tidal effects coming from the external dimension; both positive and negative values of the spacetime parameter b are considered. We restrict attention to the axisymmetric motion of string loops when the motion can be fully governed by an appropriately defined effective potential related to the energy and angular momentum of the string loops. In dependence on these two constants of the motion, the string loops can be captured, trapped, or can escape to infinity. In close vicinity of stable equilibrium points at the centre of trapped states the motion is regular. We describe how it is transformed to chaotic motion with growing energy of the string loop. In the field of naked singularities the trapped states located off the equatorial plane of the system exist and trajectories unable to cross the equatorial plane occur, contrary to the trajectories in the field of black holes where crossing the equatorial plane is always admitted. We concentrate our attention to the so called transmutation effect when the string loops are accelerated in the deep gravitational field near the black hole or naked singularity by transforming the oscillatory energy to the energy of the transitional motion. We demonstrate that the influence of the tidal charge can be substantial especially in the naked singularity spacetimes with b > 1 where the acceleration to ultrarelativistic velocities with Lorentz factor ? ? 100 can be reached, being more than one order higher in comparison with those obtained in the black hole spacetimes.

Stuchlík, Z.; Kološ, M., E-mail: zdenek.stuchlik@fpf.slu.cz, E-mail: martin.kolos@fpf.slu.cz [Institute of Physics, Faculty of Philosophy and Science, Silesian University in Opava, Bezru?ovo nám.13, CZ-74601 Opava (Czech Republic)

2012-10-01T23:59:59.000Z

499

Full-power test of a string of magnets comprising a half-cell of the Superconducting Super Collider  

SciTech Connect (OSTI)

In this paper we describe the full-powered operation of a string of industrially-fabricated magnets comprising a half-cell of the Superconducting Super Collider (SSC). The completion of these tests marks the first successful operation of a major SSC subsystem. The five 15-m long dipole magnets in the string had an aperture of 50 mm and the single 5-m long quadrupole aperture was 40 mm. Power and cryogenic connections were made to the string through spool pieces that are prototypes for SSC operations. The string was cooled to cryogenic temperatures in early July, 1992, and power tests were performed at progressively higher currents up to the nominal SSC operating point above 6500 amperes achieved in mid-August. In this paper we report on the electrical and cryogenic performance of the string components and the quench protection system during these initial tests.

Burgett, W.; Christianson, M.; Coombes, R. [and others

1992-10-01T23:59:59.000Z

500

Dynamics of a self-gravitating thin string in scalar-tensor theories of gravitation  

E-Print Network [OSTI]

We examine the dynamics of a self-gravitating string in the scalar-tensor theories of gravitation by considering a thin tube of matter to describe it. For a class of solutions, we obtain in the generic case that the extrinsic curvature of the world sheet of the central line is null in the limit where the radius of the string tends to zero. However, if we impose a specific constraint on the behaviour of the solution then we find that only the mean curvature of the world sheet of the central line vanishes which is just the Nambu-Goto dynamics. This analysis can include the massless dilatonic theories of gravity.

B. Boisseau; B. Linet

1997-06-09T23:59:59.000Z