pinecone/core-2020-05-10-deduplication huggingface dataset:
Moving finite elements method applied to dynamic population balance equations

A moving finite elements scheme is developed and used for solving 1-D dynamic population balance equations (PBE). The method stands on the weighted finite-elements based approach, and the local solutions are represented by cubic Hermite polynomials. The weighting function is the gradient of residuals with respect to time derivatives of the solution at the nodes and nodal velocities. The general PBE considered includes nucleation, growth, aggregation and breakage terms. The accuracy of the moving finite elements method (MFEM) is evaluated by comparing the results to the analytical solution in problems involving combinations of the first three phenomena considered. The formulation addressed was successful when used for solving a two- phase system representing a semibatch precipitation reactor. The MFEM enables one to achieve accurate results at reasonable CPU times, thus, showing to be adequate for these kind of problems. © 2008 American Institute of Chemical Engineers AIChE J, 2008http://dx.doi.org/10.1002/aic.1138
Perturbative Renormalisation of the Second Moment of Generalised Parton
  Distributions

We calculate the non-forward quark matrix elements of operators with two
covariant derivatives needed for the renormalisation of the second moment of
generalised parton distributions in one-loop lattice perturbation theory using
Wilson fermions. For some representations of the hypercubic group commonly used
in simulations we determine the sets of all possible mixing operators. For
those representations the one-loop mixing matrices of renormalisation factors
are found. Due to non-vanishing contributions of operators with external
ordinary derivatives the number of contributing operators increases compared to
forward matrix elements.Comment: 25 page
Mapping continuous potentials to discrete forms

The optimal conversion of a continuous inter-particle potential to a discrete
equivalent is considered here. Existing and novel algorithms are evaluated to
determine the best technique for creating accurate discrete forms using the
minimum number of discontinuities. This allows the event-driven molecular
dynamics technique to be efficiently applied to the wide range of continuous
force models available in the literature, and facilitates a direct comparison
of event-driven and time-driven molecular dynamics. The performance of the
proposed conversion techniques are evaluated through application to the
Lennard-Jones model. A surprising linear dependence of the computational cost
on the number of discontinuities is found, allowing accuracy to be traded for
speed in a controlled manner. Excellent agreement is found for static and
dynamic properties using a relatively low number of discontinuities. For the
Lennard-Jones potential, the optimized discrete form outperforms the original
continuous form at gas densities but is significantly slower at higher
densities
Uplifting the baryonic branch: a test for backreacting anti-D3-branes

Placing D3 or anti-D3-branes at the tip of the Klebanov-Strassler background
results in uplifting the baryonic branch of the moduli space of the dual field
theory. In this paper we derive a mass formula for the scalar particle
associated with the motion along the baryonic branch, from both open and closed
string points of view. We show that both methods give the same mass at linear
order in number of (anti)D3-branes, thus providing a comprehensive check for
the recently found linearized supergravity solution describing backreacting
anti-D3-branes at the tip.Comment: 26 page
An artificial Rb atom in a semiconductor with lifetime-limited linewidth

We report results important for the creation of a best-of-both-worlds quantum
hybrid system consisting of a solid-state source of single photons and an
atomic ensemble as quantum memory. We generate single photons from a GaAs
quantum dot (QD) frequency-matched to the Rb D2-transitions and then use the Rb
transitions to analyze spectrally the quantum dot photons. We demonstrate
lifetime-limited QD linewidths (1.48 GHz) with both resonant and non-resonant
excitation. The QD resonance fluorescence in the low power regime is dominated
by Rayleigh scattering, a route to match quantum dot and Rb atom linewidths and
to shape the temporal wave packet of the QD photons. Noise in the solid-state
environment is relatively benign: there is a blinking of the resonance
fluorescence at MHz rates but negligible upper state dephasing of the QD
transition. We therefore establish a close-to-ideal solid-state source of
single photons at a key wavelength for quantum technologies
Influence of the track quality and of the properties of the wheel rail rolling contact on vehicle dynamics

This work describes an analytical approach to determine what degree of accuracy is required in the definition of the rail vehicle models used for dynamic simulations. This way it would be possible to know in advance how the results of simulations may be altered due to the existence of errors in the creation of rolling stock models, whilst also identifying their critical parameters. This would make it possible to maximize the time available to enhance dynamic analysis and focus efforts on factors that are strictly necessary.In particular, the parameters related both to the track quality and to the rolling contact were considered in this study. With this aim, a sensitivity analysis was performed to assess their influence on the vehicle dynamic behaviour. To do this, 72 dynamic simulations were performed modifying, one at a time, the track quality, the wheel-rail friction coefficient and the equivalent conicity of both new and worn wheels. Three values were assigned to each parameter, and two wear states were considered for each type of wheel, one for new wheels and another one for reprofiled wheels.After processing the results of these simulations, it was concluded that all the parameters considered show very high influence, though the friction coefficient shows the highest influence. Therefore, it is recommended to undertake any future simulation job with measured track geometry and track irregularities, measured wheel profiles and normative values of wheel-rail friction coefficient
Gauge invariant 1PI effective action for superstring field theory

We construct gauge invariant 1PI effective action for the NS sector of type II and heterotic string field theory. By construction, zero eigenvalues of the kinetic operator of this action determine the renormalized physical masses, and tree level amplitudes computed from this action (after gauge fixing) give the loop corrected S-matrix elements. Using this formalism we can give a simple proof of the result that the renormalized physical masses do not depend on the choice of local coordinate system and locations of picture changing operators used in defining the off-shell amplitude. We also eliminate the need for an infrared regulator in dealing with tadpoles of massless fields
N-jettiness subtractions for NNLO QCD calculations

We present a subtraction method utilizing the N -jettiness observable, T N , to perform QCD calculations for arbitrary processes at next-to-next-to-leading order (NNLO). Our method employs soft-collinear effective theory (SCET) to determine the IR singular contributions of N -jet cross sections for T N → 0, and uses these to construct suitable T N -subtractions. The construction is systematic and economic, due to being based on a physical observable. The resulting NNLO calculation is fully differential and in a form directly suitable for combining with resummation and parton showers. We explain in detail the application to processes with an arbitrary number of massless partons at lepton and hadron colliders together with the required external inputs in the form of QCD amplitudes and lower-order calculations. We provide explicit expressions for the T N -subtractions at NLO and NNLO. The required ingredients are fully known at NLO, and at NNLO for processes with two external QCD partons. The remaining NNLO ingredient for three or more external partons can be obtained numerically with existing NNLO techniques. As an example, we employ our results to obtain the NNLO rapidity spectrum for Drell-Yan and gluon-fusion Higgs production. We discuss aspects of numerical accuracy and convergence and the practical implementation. We also discuss and comment on possible extensions, such as more-differential subtractions, necessary steps for going to N 3 LO, and the treatment of massive quarks
A bioturbation classification of European marine infaunal invertebrates

Bioturbation, the biogenic modification of sediments through particle reworking and burrow ventilation, is a key mediator of many important geochemical processes in marine systems. In situ quantification of bioturbation can be achieved in a myriad of ways, requiring expert knowledge, technology, and resources not always available, and not feasible in some settings. Where dedicated research programmes do not exist, a practical alternative is the adoption of a trait-based approach to estimate community bioturbation potential (BPc). This index can be calculated from inventories of species, abundance and biomass data (routinely available for many systems), and a functional classification of organism traits associated with sediment mixing (less available). Presently, however, there is no agreed standard categorization for the reworking mode and mobility of benthic species. Based on information from the literature and expert opinion, we provide a functional classification for 1033 benthic invertebrate species from the northwest European continental shelf, as a tool to enable the standardized calculation of BPc in the region. Future uses of this classification table will increase the comparability and utility of large-scale assessments of ecosystem processes and functioning influenced by bioturbation (e.g., to support legislation). The key strengths, assumptions, and limitations of BPc as a metric are critically reviewed, offering guidelines for its calculation and application
Gradient methods for variational optimization of projected
  entangled-pair states

We present a conjugate-gradient method for the ground-state optimization of
projected entangled-pair states (PEPS) in the thermodynamic limit, as a direct
implementation of the variational principle within the PEPS manifold. Our
optimization is based on an efficient and accurate evaluation of the gradient
of the global energy functional by using effective corner environments, and is
robust with respect to the initial starting points. It has the additional
advantage that physical and virtual symmetries can be straightforwardly
implemented. We provide the tools to compute static structure factors directly
in momentum space, as well as the variance of the Hamiltonian. We benchmark our
method on Ising and Heisenberg models, and show a significant improvement on
the energies and order parameters as compared to algorithms based on
imaginary-time evolution
Azimuthal Angle Correlations for Higgs Boson plus Multi-Jet Events

At lowest order in perturbation theory, the scattering matrix element for Higgs boson production in association with dijets displays a strong correlation in the azimuthal angle between the dijets, induced by the CP-properties of the Higgs Boson coupling. However, the phase space cuts necessary for a clean extraction of the CP-properties simultaneously induce large corrections from emissions of hard radiation and thus formation of extra jets. The current study concerns the generalization of CP-studies using the azimuthal angle between dijets beyond tree-level and to events with more than just two jets. By analyzing the High Energy Limit of hard scattering matrix elements we arrive at a set of cuts optimized to enhance the correlation, while maintaining a large cross section, and an observable, which is very stable against higher order corrections. We contrast the description of Higgs boson production in association with jets at different levels: for tree-level hjj and hjjj matrix elements, for hjj matrix elements plus parton shower, and in a recent all-order framework, which converges to the full, all-order perturbative result in the limit of large invariant mass between all produced particles
Nuclear charge radii and electric monopole transitions in the interacting boson model

8 pages, 5 figures, to be published in AIP Conference Proceedings, Proceedings of the International Conference on Beauty in Physics: Theory and Experiment, Cocoyoc, Mexico, May 12-18, 2012International audienceThe interacting boson model (IBM) of Arima and Iachello is applied to calculate nuclear charge radii and electric monopole transitions of even-even nuclei in the rare-earth region. Consistent operators are used for the two observables. A relation between summed M1 strength and $\rho({\rm E0})$ values is pointed out
Technology and Sociomaterial Performation

Part 1: IS/IT Implementation and AppropriationInternational audienceOrganizational researchers have acknowledged that understanding the relationship between technology and organization is crucial to understanding modern organizing and organizational change [1]. There has been a significant amount of debate concerning the theoretical foundation of this relationship. Our research draws and extends Deleuze and DeLanda’s work on assemblages and Callon’s concept of performation to investigate how different sociomaterial practices are changed and stabilized after the implementation of new technology. Our findings from an in-depth study of two ambulatory clinics within a hospital system indicate that “perform-ing” of constituting, counter-performing, calibrating, and stratifying explained the process of sociomaterial change and that this process is governed by an overarching principle of “performative exigency”. Future studies on sociomateriality and change may benefit from a deeper understanding of how sociomaterial assemblages are rendered performative
Cryoprotective effect of low-sweetness additives on protein denaturation of threadfin bream surimi (Nemipterusspp.) during frozen storage

The cryoprotective effects of lactitol, maltodextrin, palatinit, polydextrose, trehalose on the protein denaturation of threadfin bream surimi during six months of frozen storage were investigated. The characteristics analyzed were Ca2þ-ATPase activity, protein solubility, sulfhydryl (SH) content, electrophoresis, surface morphology, and thermal stability. The effectiveness of all cryoprotectants generally decreased as the storage time increased. Polydextrose was able to maintain Ca2þ-ATPase activity, protein solubility, and SH content of 33.5%, 71.3%, 71.8%, respectively. Sucrose was able to maintain Ca2þ-ATPase activity, protein solubility, and SH content of 32.4%, 68.1%, 75.6%, respectively. Electrophoresis showed that the myosin heavy chain (MHC) and actin band intensity almost disappeared by the end of storage. Analysis by scanning electron microscopy (SEM) demonstrated that the number of pores formed increased after storage. Thermal stability analysis showed a decrease in myosin but no significant change in actin content. This study suggests that polydextrose as a cryoprotectant is able to maintain protein from denaturation as the same as sucrose
Variational convergences of dual energy functionals for elastic materials with a ε thin strong inclusion

International audienceWe give a new derivation, based on the complementary energy formulation, of a simplified model for a multi-structure made up of two anisotropic hyper-elastic bodies connected by a thin strong material layer. The model is obtained by identifying the Mosco limit of the stored complementary energy functional when the thickness is of order ε and the stiffness of order 1/ε where ε is a positive real adimensional parameter. In order to prove the existence of the displacement associated with the stress we use a suitable weak version of the Saint-Venant compatibility condition also known as Donati's theorem
Asymptotic behavior of a compressible two-phase model with well–formation interaction.

In this work we consider a compressible gas–liquid model with a well–reservoir interaction term that is relevant for coupled wellbore-reservoir ﬂow systems involved in e.g. drilling operations. Main focus is on deriving estimates that are independent of time. Under suitable conditions on the well–reservoir interaction term we obtain such estimates which allow prediction of the long-time behavior of the gas and liquid masses. Moreover, we also obtain a quantiﬁcation of the convergence rates as a function of time and gain some insight into the role played by the rate characterizing how fast the well–reservoir interaction must die out. The model is investigated in a free boundary setting where the initial mass is a mixture of both phases, i.e. no single-phase zone exists
Statistical and Numerical Study of Asteroid Orbital Uncertainty

International audienceThe knowledge of the orbit or the ephemeris uncertainty of asteroid presents a particular interest for various purposes. These quantities are for instance useful for recovering asteroids, for identifying lost asteroids or for planning stellar occultation campaigns. They are also needed to estimate the close approach of Near-Earth asteroids, and subsequent risk of collision. Ephemeris accuracy can also be used for instrument calibration purposes or for scientific applications. Asteroid databases provide information about the uncertainty of the orbits allowing the measure of the quality of an orbit. The aims of this paper is to analyse these different uncertainty parameters and to estimate the impact of the different measurements on the uncertainty of orbits. We particularly deal with two main databases ASTORB and MPCORB providing uncertainty parameters for asteroid orbits. Statistical methods are used in order to estimate orbital uncertainty and compare with parameters from databases. Simulations are also generated to deal with specific measurements such as future Gaia or present radar measurements. Relations between the uncertainty parameter and the characteristics of the asteroid (orbital arc, absolute magnitude, ...) are highlighted. Moreover, a review of the different measuments are compiled and the impact of these measures on the accuracy of the orbit is also estimated
X-ray follow-up observations of the two γ-ray pulsars PSR J1459–6053 and PSR J1614–2230

International audienceAims. We have observed two newly detected γ-ray pulsars, PSR J1459−6053 and PSR J1614−2230, in the X-ray domain withXMM-Newton to try to enlarge the sample of pulsars for which multi-wavelength data exist. We use these data with the aim of understandingthe pulsar emission mechanisms of these pulsars.Methods. We analysed the X-ray spectra to determine whether the emission emanates from the neutron star surface (thermal emission)or from the magnetosphere (non-thermal emission) and compared this to the region in the magnetosphere in which the γ-rayemission is generated. Furthermore, we compared the phase-folded X-ray lightcurves with those in the γ-ray and, where possible,radio domains, to elicit additional information on the emission sites.Results. J1459−6053 shows X-ray spectra that are best fitted with a power law model with a photon index Γ = 2.10+1.24−0.85. The γ-raydata suggest that either the slot gap or the outer gap model may be best to describe the emission from this pulsar. Analysis of theX-ray lightcurve folded on the γ-ray ephemeris shows modulation at the 3.7σ level in the 1.0−4.5 keV domain. Possible alignmentof the main γ-ray and X-ray peaks also supports the interpretation that the emission in the two energy domains emanates from similarregions. The millisecond pulsar J1614−2230 exhibits an X-ray spectrum with a substantial thermal component, where the best-fittingspectral model is either two blackbodies, with kT = 0.15+0.04−0.04 and 0.88+2.54−0.54 keV or a blackbody with similar temperature to the previouscooler component, kT = 0.13+0.04−0.02 keV and a power law component with a photon index Γ = 1.25+2.30−1.75. The cooler blackbodycomponent is likely to originate from the hot surface at the polar cap. Analysis of the X-ray lightcurve folded on the radio ephemerisshows modulation at the 4.0σ level in the 0.4−3.0 keV domain
Quasigeostrophic model of the instabilities of the Stewartson layer in flat and depth-varying containers

12 pagesDetached shear layers in a rotating container, known as Stewartson layers, become unstable for a critical shear measured by the Rossby number Ro. To study rapidly rotating flows at asymptotically small Rossby and Ekman numbers E, a quasigeostrophic (QG) model is developed, whose main original feature is to enforce mass conservation properly, and valid for any container provided that the top and bottom have finite slopes. Asymptotic scalings of the Stewartson instability are deduced from the linear QG model, extending the previous analyses to large slopes (as in a sphere). For a flat container, the critical Rossby number evolves as E^(3/4) and the instability can be understood as a shear instability. For a depth-varying container, the instability is quite different: it is a Rossby wave with a critical Rossby number proportional to beta E^(1/2), where beta is related to the slope. A numerical implementation of the QG model is used to determine the critical parameters for different Ekman numbers (as low as 10-10) and to describe the instability at the onset for different geometries. We also investigate the asymmetry between positive and negative Ro and propose an explanation based on the location of the instability. For flat cylindrical containers, the QG numerical results are directly compared to existing experimental data obtained by Niino and Misawa [J. Atmos. Sci. 41, 1992 (1984)] and Fruh and Read [J. Fluid Mech. 383, 143 (1999)]. We present new experimental results of the destabilization of a Stewartson layer in a rotating spheroid, caused by the differential rotation of two disks or a central inner core. These experiments are compared to the numerical QG results obtained in a split sphere, validating the QG model, and allowing us to show its limits. For spherical shells, the experimental critical curves agree to the ones obtained by three-dimensional calculations of Hollerbach [J. Fluid Mech. 492, 289 (2003)]