pinecone/core-2020-05-10-deduplication huggingface dataset:
Nonlinear control of unsteady finite-amplitude perturbations in the Blasius boundary-layer flow

The present work provides an optimal control strategy, based on the nonlinear
Navier–Stokes equations, aimed at hampering the rapid growth of unsteady finite-amplitude perturbations in a Blasius boundary-layer flow. A variational procedure is used to find the blowing and suction control law at the wall providing the maximum damping of the energy of a given perturbation at a given target time, with the final aim of leading the flow back to the laminar state. Two optimally growing finite-amplitude initial perturbations capable of leading very rapidly to transition have been used to initialize the flow. The nonlinear control procedure has been found able to drive such perturbations back to the laminar state, provided that the target time of the minimization and the region in which the blowing and suction is applied have been suitably chosen. On the other hand, an equivalent control procedure based on the linearized Navier–Stokes equations has been found much less effective, being not able to lead the flow to the laminar state when finite-amplitude disturbances are considered. Regions of strong sensitivity to blowing and suction have been also identified for the given initial perturbations: when the control is actuated in such regions, laminarization is also observed for a shorter extent of the actuation region. The nonlinear optimal blowing and suction law consists of alternating wall-normal velocity perturbations, which appear to modify the core flow structures by means of two distinct mechanisms: (i) a wall-normal velocity compensation at small times; (ii) a rotation-counterbalancing effect al larger times. Similar control laws have been observed for different target times, values of the cost parameter, and streamwise extents of the blowing and suction zone, meaning that these two mechanisms are robust features of the optimal control strategy, provided that the nonlinear effects are taken into account
A fingerprint based metric for measuring similarities of crystalline
  structures

Measuring similarities/dissimilarities between atomic structures is important
for the exploration of potential energy landscapes. However, the cell vectors
together with the coordinates of the atoms, which are generally used to
describe periodic systems, are quantities not suitable as fingerprints to
distinguish structures. Based on a characterization of the local environment of
all atoms in a cell we introduce crystal fingerprints that can be calculated
easily and allow to define configurational distances between crystalline
structures that satisfy the mathematical properties of a metric. This distance
between two configurations is a measure of their similarity/dissimilarity and
it allows in particular to distinguish structures. The new method is an useful
tool within various energy landscape exploration schemes, such as minima
hopping, random search, swarm intelligence algorithms and high-throughput
screenings
Current ozone levels threaten gross primary production and yield of Mediterranean annual pastures and nitrogen modulates the response

Pastures are among the most important ecosystems in Europe considering their biodiversity and dis-\ud
tribution area. However, their response to increasing tropospheric ozone (O\ud
3\ud
) and nitrogen (N) deposi-\ud
tion, two of the main drivers of global change, is still uncertain. A new Open-Top Chamber (OTC)\ud
experiment was performed in central Spain, aiming to study annual pasture response to O\ud
3\ud
and N in close\ud
to natural growing conditions. A mixture of six species of three representative families was sowed in the\ud
fi\ud
eld. Plants were exposed for 40 days to four O\ud
3\ud
treatments:\ud
fi\ud
ltered air, non-\ud
fi\ud
ltered air (NFA) repro-\ud
ducing ambient levels and NFA supplemented with 20 and 40 nl l\ud
�\ud
1\ud
O\ud
3\ud
. Three N treatments were\ud
considered to reach the N integrated doses of\ud
“\ud
background\ud
”\ud
,\ud
þ\ud
20 or\ud
þ\ud
40 kg N ha\ud
�\ud
1\ud
. Ozone signi\ud
fi\ud
cantly\ud
reduced green and total aboveground biomass (maximum reduction 25%) and increased the senescent\ud
biomass (maximum increase 40%). Accordingly, O\ud
3\ud
decreased community Gross Primary Production due\ud
to both a global reduction of ecosystem CO\ud
2\ud
exchange and an increase of ecosystem respiration. Nitrogen\ud
could partially counterbalance O\ud
3\ud
effects on aboveground biomass when the levels of O\ud
3\ud
were moderate,\ud
but at the same time O\ud
3\ud
exposure reduced the fertilization effect of higher N availability. Therefore, O\ud
3\ud
must be considered as a stress factor for annual pastures in the Mediterranean areas
Measurement of $CP$ asymmetries and polarisation fractions in $B_s^0 \rightarrow K^{*0}\bar{K}{}^{*0}$ decays

An angular analysis of the decay $B_s^0 \rightarrow K^{*0}\bar{K}{}^{*0}$ is performed using $pp$ collisions corresponding to an integrated luminosity of $1.0$ ${fb}^{-1}$ collected by the LHCb experiment at a centre-of-mass energy $\sqrt{s} = 7$ TeV. A combined angular and mass analysis separates six helicity amplitudes and allows the measurement of the longitudinal polarisation fraction $f_L = 0.201 \pm 0.057 {(stat.)} \pm 0.040{(syst.)}$ for the $B_s^0 \rightarrow K^*(892)^0 \bar{K}{}^*(892)^0$ decay. A large scalar contribution from the $K^{*}_{0}(1430)$ and $K^{*}_{0}(800)$ resonances is found, allowing the determination of additional $CP$ asymmetries. Triple product and direct $CP$ asymmetries are determined to be compatible with the Standard Model expectations. The branching fraction $\mathcal{B}(B_s^0 \rightarrow K^*(892)^0 \bar{K}{}^*(892)^0)$ is measured to be $(10.8 \pm 2.1 {\ \rm (stat.)} \pm 1.4 {\ \rm (syst.)} \pm 0.6 \ (f_d/f_s) ) \times 10^{-6}$
Hierarchical Pairwise Segmentation using Dominant Sets and Anisotropic Diffusion Kernels

Pairwise data clustering techniques are gaining increasing popularity over traditional, feature-based central grouping techniques. These approaches have proved very powerful when applied to image-segmentation problems. However, they are mainly focused on extracting flat partitions of the data, thus missing out on the advantages of the inclusion constraints typical of hierarchical coarse-to-fine segmentations approaches very common when working directly on the image lattice. In this paper we present a pairwise hierarchical segmentation approach based on dominant sets [12] where an anisotropic diffusion kernel allows for a scale variation for the extraction of the segments, thus enforcing separations on strong boundaries at a high level of the hierarchy. Experimental results on the standard Berkeley database [9] show the effectiveness of the approach
A graph-based technique for semi-supervised segmentation of 3D surfaces

A wide range of cheap and simple to use 3D scanning devices has recently been introduced in the market.\ud
These tools are no longer addressed to research labs and highly skilled professionals, but rather, they are\ud
mostly designed to allow inexperienced users to acquire surfaces and whole objects easily and independently. In this scenario, the demand for automatic or semi-automatic algorithms for 3D data processing is\ud
increasing. In this paper we address the task of segmenting the acquired surfaces into perceptually\ud
relevant parts. Such a problem is well known to be ill-deﬁned both for 2D images and 3D objects, as even with a perfect understanding of the scene, many different and incompatible semantic or syntactic segmentations can exist together. For this reason recent years have seen a great research effort into semi-supervised approaches, that can make use of small bits of information provided by the user to attain better accuracy. We propose a semi-supervised procedure that exploits an initial set of seeds selected by the user. In our framework segmentation happens by propagating part labels over a weighted graph representation of the surface directly derived from its triangulated mesh. The assignment of each element is driven by a greedy approach that accounts for the curvature between adjacent triangles. The proposed\ud
technique does not require to perform edge detection or to ﬁt parametrized surfaces and its implementation is very straightforward. Still, despite its simplicity, tests made on a standard database of scanned 3D objects show its effectiveness even with moderate user supervisio
A framework for redescription set construction

Redescription mining is a field of knowledge discovery that aims at finding
different descriptions of similar subsets of instances in the data. These
descriptions are represented as rules inferred from one or more disjoint sets
of attributes, called views. As such, they support knowledge discovery process
and help domain experts in formulating new hypotheses or constructing new
knowledge bases and decision support systems. In contrast to previous
approaches that typically create one smaller set of redescriptions satisfying a
pre-defined set of constraints, we introduce a framework that creates large and
heterogeneous redescription set from which user/expert can extract compact sets
of differing properties, according to its own preferences. Construction of
large and heterogeneous redescription set relies on CLUS-RM algorithm and a
novel, conjunctive refinement procedure that facilitates generation of larger
and more accurate redescription sets. The work also introduces the variability
of redescription accuracy when missing values are present in the data, which
significantly extends applicability of the method. Crucial part of the
framework is the redescription set extraction based on heuristic
multi-objective optimization procedure that allows user to define importance
levels towards one or more redescription quality criteria. We provide both
theoretical and empirical comparison of the novel framework against current
state of the art redescription mining algorithms and show that it represents
more efficient and versatile approach for mining redescriptions from data
A survey of dioxin-like contaminants in fish from recreational fishing.

The dioxin and dioxin-like compounds are regarded as one of the most toxic group of environmental
contaminants. Food for the commercial market is regularly monitored for their dioxin levels and the concentration allowed in food is strictly regulated. Less is known about locally caught fish from recreational fishing, which is often brought home for consumption. This can be fish caught from nearby lakes or streams or fish with marine origin close to industrial areas or harbours that are not regularly monitored for their dioxin levels. In this study, we established collaboration with schools
in 13 countries. We received 203 samples of 29 different fish species of which Atlantic cod was the most abundant followed by brown trout and pollock. In general, the majority of samples from the participating countries had low concentrations (between 0.1 and 0.2 pg/g chemical-activated luciferase gene expression toxic equivalency wet weight (CALUX TEQ w.w.)) of dioxins
and dioxin-like PCBs. Only 18 samples had concentrations above 1 pg/g CALUX TEQ w.w., and only 2 dab samples had concentration above maximum levels set by the European Commission. The Atlantic cod samples showed a significant reduction in the concentrations of dioxins with increasing latitude indicating less contamination of dioxin and dioxin-like compounds in the north of Norway. The results indicate that a moderate consumption of self-caught fish at presumed non-contaminated sites does not represent a major risk for exposure to dioxins or dioxin-like compounds at concentrations associated with adverse health effects. Recreational fishermen should, however, obtain knowledge about local fish consumption advice
DIRAC framework evaluation for the Fermi-LAT and CTA experiments DIRAC framework evaluation for the Fermi -LAT and CTA experiments

International audienceDIRAC (Distributed Infrastructure with Remote Agent Control) is a general framework for the management of tasks over distributed heterogeneous computing environments. It has been originally developed to support the production activities of the LHCb (Large Hadron Collider Beauty) experiment and today is extensively used by several particle physics and biology communities. Current (Fermi Large Area Telescope – LAT) and planned (Cherenkov Telescope Array – CTA) new generation astrophysical/cosmological experiments, with very large processing and storage needs, are currently investigating the usability of DIRAC in this context. Each of these use cases has some peculiarities: Fermi-LAT will interface DIRAC to its own workflow system to allow the access to the grid resources, while CTA is using DIRAC as workflow management system for Monte Carlo production and analysis on the grid. We describe the prototype effort that we lead toward deploying a DIRAC solution for some aspects of Fermi-LAT and CTA needs. 1. Introduction The Large Area Telescope (LAT) is the primary instrument on the Fermi Gamma-ray Space Telescope mission, launched on June 11, 2008. It is the product of an international collaboration between DOE, NASA and academic US institutions as well as international partners in France, Italy, Japan and Sweden. The LAT is a pair-conversion detector of high-energy gamma rays covering the energy range from 20 MeV to more than 300 GeV [1]. It has been designed to detect gamma rays in a broad energy range, with good position resolution (<10 arcmin) and an energy resolution of ∼10%. The LAT has been routinely monitoring the gamma-ray sky and has shed light on the extreme, non-thermal Universe. A brief and recent review of Fermi-LAT discoveries can be found in [2]
Mass spectrometry (fragmentation ratios) of DNA base molecules following 80 keV proton impact with separation of direct ionization and electron capture processes

To be published International Journal of Mass SpectrometryThe first fragmentation ratios are presented for the ionization and dissociative ionization of gas-phase DNA bases following 80 keV (1.8 v0) proton impact. Event-by-event determination of the projectile charge state after collision enables also to distinguish the relative contributions of electron capture (EC) by the projectile from direct ionization (DI) of the target molecule (without projectile neutralization) thus yielding branching rations for these two different ionization processes. Results have been compared with recent similar experiments on uracil [Tabet et al. unpublished] and water [Gobet et al. Phys. Rev. A 70 (2004) 062716]. Although in all cases both processes (EC and DI) produced the same fragment ion groups in the mass spectra, fragmentation is for EC larger than for DI. Moreover the fragmentation ratio for dissociative ionization was observed to be for thymine larger than for adenine, cytosine, and uracil
Bilinear control of high frequencies for a 1D Schrödinger equation

International audienceIn this article, we consider a 1D linear Schrödinger equation with potential V and bilinear control. Under appropriate assumptions on V , we prove the exact controllability of high frequencies, in H 3 , locally around any H 3-trajectory of the free system. In particular, any initial state in H 3 can be steered to a regular state, for instance a nite sum of eigen-functions of (−∆ + V). This fact, coupled with a previous result due to Nersesyan, proves the global exact controllability of the system in H 3 , with smooth controls, under appropriate assumptions
Competitive and Cooperative Degree in Supply Chain: Supplier Selection between Competitors and Third-Party Suppliers

Part 5: Modelling and SimulationInternational audienceThis work explores the firm’s supplier selection question that the competitor firm and the third-party supplier can supply the substitutable component. We consider a supply chain with two competing original equipment manufacturers (OEMs) and two third-party suppliers. The two OEMs produce the competing products which are comprised by two main components. Each OEM only can produce one component in-house and each third-party supplier only supplies one component. The OEMs must decide whether to outsource the other component to the competing OEM or to a third-party supplier. We discuss the different supplier selection strategies and compare the OEMs profits in different decision. We find that there are conditions where, while one of the OEMs should outsource to the competing firm, outsourcing to a third-party supplier is the optimal strategy for the other OEM even when the cost of the third-party supplier is more expensive and the competition is intense
Closed-Loop Autofocus Scheme for Scanning Electron Microscope

International audienceIn this paper, we present a full scale autofocus approach for scanning electron microscope (SEM). The optimal focus (in-focus) position of the microscope is achieved by maximizing the image sharpness using a vision-based closed-loop control scheme. An iterative optimization algorithm has been designed using the sharpness score derived from image gradient information. The proposed method has been implemented and validated using a tungsten gun SEM at various experimental conditions like varying raster scan speed, magnification at real-time. We demonstrate that the proposed autofocus technique is accurate, robust and fast
Stability analysis of a polymer film casting problem

This is the accepted version of the following article: Kallel, A, Hachem, E, Rapetti, F, Demay, Y, and Agassant, JF (2015), Stability analysis of a polymer film casting problem. Int. J. Numer. Meth. Fluids, 78, 436–454. doi: 10.1002/fld.4024, which has been published in final form at http://dx.doi.org/10.1002/fld.4024International audienceThe polymer cast film process consists of stretching a molten polymer film between a flat die and a drawing roll. Drawing instabilities are often encountered and represent a drastic limitation to the process. Newtonian fluid film stretching stability is investigated using two numerical strategies. The first one is a ‘tracking’ method, which consists of solving Stokes equations in the whole fluid area (extrusion die and stretching path) by finite elements. The interface is determined to satisfy a kinematic equation. A domain decomposition meshing technique is used in order to account for a flow singularity resulting from the change in the boundary conditions between the die flow region and the stretching path region. A linear stability method is then applied to this transient kinematic equation in order to investigate the stability of the stationary solution. The second method is a direct finite element simulation in an extended area including the fluid and the surrounding air. The time-dependent interface is captured by solving an appropriate level-set function. The agreement between the two methods is fair. The influence of the stretching parameters (Draw ratio and drawing length) is investigated. For a long stretching distance, a critical Draw ratio around 20 delimitating stable and unstable drawing conditions is obtained, and this agrees well with the standard membrane models, which have been developed 40 years ago. When decreasing the stretching distance, the membrane model is no longer valid. The 2D models presented here point out a significant increase of the critical Draw ratio, and this is consistent with experimental results
The influence of sex stereotypes and gender roles on participation and performance in sport and exercise: Review and future directions

International audienceThe role of sex stereotypes and gender roles in the sex differences observed in sport and exercise has been extensively investigated in sport psychology, past studies showing that stereotypes are internalized into the self during the socialization process. Although this research has provided clear evidence of the psychosocial roots of sex differences in athletics, focusing exclusively on an internalization explanation may not allow a complete understanding of the influence of stereotypes in this domain. This article presents two approaches that have been developed in mainstream psychology and discusses their relevance in sport psychology: (1) the situational approach, which considers that the mere presence of stereotypes in the environment is sufficient to affect individuals (e.g., stereotype threat theory); (2) the content of stereotypes approach (e.g., stereotype content model), which suggests that stereotypes about a particular group may be ambivalent, and that this ambivalence may serve to legitimize the status quo
ODIN: a new model and ephemeris for the Pluto system

Reproduced with permission. Copyright ESO. The original publication is available at www.aanda.org.International audienceBecause of Pluto's distance from the Sun, the Pluto system has not yet completed a revolution since its discovery, hence an uncertain heliocentric distance. In this paper, we present the fitting of our dynamical model ODIN (Orbite, Dynamique et Intégration Numérique) to observations. The small satellites P4 and P5 are not taken into account. We fitted our model to the measured absolute coordinates (RA, DEC) of Pluto, and to the measured positions of the satellites relative to Pluto. The masses we found for the bodies of the system are consistent with those of previous studies. Yet the masses of the small satellites Nix and Hydra are artificially constrained by the number of observations of Charon. The best way to improve the determination of their masses would be to use observations of P4 and P5, but there are still not enough published observations. Concerning the heliocentric distance of the system, we compared the value we obtained using ODIN and those of other models. The difference between the models far exceeds the uncertainty needed (about 1000 km) for the mission New Horizons. A new astrometric reduction of old photographic plates may be an efficient way to constrain this distance. The ephemeris for Pluto's satellites is available on the web page of the IMCCE at http://www.imcce.fr/hosted_sites/saimirror/nssreq9hf.htm. The complete version of the ephemeris is available as a SPICE kernel at http://www.imcce.fr/~beauvalet/. Appendices A and B are available in electronic form at http://www.aanda.orgTable A.2 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/553/A1
Structure of chalcogenide glasses by neutron diffraction

5 pages. Proceedings International Workshop Non-crystalline Solids, Gijon (Spain).International audienceThe purpose of this work is to study the change in the structure of the Ge-Se network upon doping with Ag. The total structure factor S(Q) for two samples has been measured by neutron diffraction using the two-axis diffractometer dedicated to structural studies of amorphous materials, D4, at the Institut Laue Langevin. We have derived the corresponding radial distribution functions for each sample and each temperature, which gives us an insight about the composition and temperature dependence of the correlation distances and coordination numbers in the short-range. Our results are compatible with the presence of both GeSe4/2 tetrahedra and Se-Se bonds. The Ag atoms are linked to Se in a triangular environment. Numerical simulations allowing the identification of the main peaks in the total pair correlation functions have complemented the neutron diffraction measurements