pinecone/core-2020-05-10-deduplication huggingface dataset:
Formally Defining and Iterating Infinite Models

International audienceThe wide adoption of MDE raises new situations where we need to manipulate very large models or even infinite model streams gathered at runtime. These new uses cases for MDE raise challenges that had been unforeseen by the time standard modeling framework were designed. This paper proposes a formal definition of an infinite model, as well as a formal framework to reason on queries over infinite models. This formal query definition aims at supporting the design and verification of operations that manipulate infinite models. First, we precisely identify the MOF parts which must be refined to support infinite structure. Then, we provide a formal coinductive definition dealing with unbounded and potentially infinite graph-based structure
Synthesis, electrochemical and spectroscopic investigations of news N-BEDOT derivatives containing anil substituted carbazole subunits.

International audienceA conjugated oligomer containing central bi-ethylenedioxythiophene (BEDOT) unit and two terminal anil-substituted carbazole units has been characterized by cyclic voltammetry and spectroelectrochemical methods (UV-vis-NIR and Raman). It shows two oxidation waves at −0.01V and +0.24V (versus Fc/Fc+), which can be ascribed to two successive oxidative dopings of the molecule. The molecule is transmissive sharp yellow when fully reduced, transmissive green upon oxidation up to the end of the first oxidative process, and dark blue upon full oxidation. UV-vis-NIR and Raman spectroelectrochemical investigations showthat the colour changes within the potential of the first oxidationwave are associated with the oxidation of both carbazole and ethylenedioxythiophene subunits whereas the electrochromic effect in the potential range of the second oxidation wave involves predominantly the oxidation of the ethylenedioxythiophene subunits
Use of the GATE Monte Carlo package for dosimetry applications

6 pages, 3 figures - submitted to NIM A, presented by D. VisvikisInternational audienceOne of the roles for MC simulation studies is in the area of dosimetry. A number of different codes dedicated to dosimetry applications are available and widely used today, such as MCNP, EGSnrc and PTRAN. However, such codes do not easily facilitate the description of complicated 3D sources or emission tomography systems and associated data flow, which may be useful in different dosimetry application domains. Such problems can be overcome by the use of specific MC codes such as GATE, which is based on Geant4 libraries, providing a scripting interface with a number of advantages for the simulation of SPECT and PET systems. Despite this potential, its major disadvantage is in terms of efficiency involving long execution times for applications such as dosimetry. The strong points and disadvantages of GATE in comparison to other dosimetry specific codes are discussed and illustrated in terms of accuracy, efficiency and flexibility. A number of features, such as the use of voxelised and moving sources, as well as developments such as advanced visualisation tools and the development of dose estimation maps allowing GATE to be used for dosimetry applications are presented. In addition, different examples from dosimetry applications with GATE are given. Finally, future directions with respect to the use of GATE for dosimetry applications are outlined
Human ecological niches and ranges during the LGM in Europe derived from an application of eco-cultural niche modeling

International audienceWe apply eco-cultural niche modeling (ECNM), an heuristic approach adapted from the biodiversity sciences, to identify habitable portions of the European territory for Upper Paleolithic hunter-gatherers during the Last Glacial Maximum (LGM), circumscribe potential geographic extents of the Solutrean and Epigravettian technocomplexes, evaluate environmental and adaptive factors that influenced their distributions, and discuss this method's potential to illuminate past human-environment interaction. Our ECNM approach employed the Genetic Algorithm for Rule-Set Prediction (GARP) and used as input a combination of archaeological and geographic data, in conjunction with high-resolution paleoclimatic simulations for this time frame. The archaeological data consist of geographic coordinates of sites dated by Accelerator Mass Spectrometry to the LGM and attributed to the Solutrean and Epigravettian technocomplexes. The areas predicted by ECNM consistently outline the northern boundary of human presence at 22,000–20,000 cal BP. This boundary is mainly determined by climatic constraints and corresponds well to known southern limits of periglacial environments and permafrost conditions during the LGM. Differences between predicted ecological niches and known ranges of the Solutrean and Epigravettian technocomplexes are interpreted as Solutrean populations being adapted to colder and more humid environments and as reflecting influences of ecological risk on geographic distributions of cultures
Riemannian-geometric entropy for measuring network complexity

International audienceA central issue in the science of complex systems is the quantitative characterization of complexity. In the present work we address this issue by resorting to information geometry. Actually we propose a constructive way to associate with a—in principle, any—network a differentiable object (a Riemannian manifold) whose volume is used to define the entropy. The effectiveness of the latter in measuring network complexity is successfully proved through its capability of detecting a classical phase transition occurring in both random graphs and scale-free networks, as well as of characterizing small exponential random graphs, configuration models, and real networks
Direct evidence for minority spin gap in the Co 2 MnSi Heusler compound

International audienceHalf metal magnets are of great interest in the field of spintronics because of their potential full spin polarization at the Fermi level (E F) and low magnetization damping. The high Curie temperature and the predicted 0. 7 eV minority spin gap make the Co 2 MnSi Heusler compound very promising for applications. We investigated the half-metallic magnetic character of this compound using spin-resolved photoemission , ab initio calculation , and ferromagnetic resonance. At the surface of Co 2 MnSi , a gap in the minority spin channel is observed , leading to 100% spin polarization. However , this gap is 0. 3 eV below E F , and a minority spin state is observed at E F. We show that a minority spin gap at E F can nevertheless be recovered either by changing the chemical composition of the compound or by covering the surface by Mn , MnSi , or MgO. This spin-gap recovery results in extremely small damping coefficients , reaching values as low as 7 × 10 −4
Handcrafted Inversions Made Operational on Operational Semantics

International audienceWhen reasoning on formulas involving large-size inductively defined relations, such as the semantics of a real programming language, many steps require the inversion of a hypothesis. The built-in "inversion" tactic of Coq can then be used, but it suffers from severe controllability, maintenance and efficiency issues, which makes it unusable in practice in large applications. To circumvent this issue, we propose a proof technique based on the combination of an antidiagonal argument and the impredicative encoding of inductive data-structures. We can then encode suitable helper tactics in LTac, yielding scripts which are much shorter (as well as corresponding proof terms) and, more importantly, much more robust against changes in version changes in the background software. This is illustrated on correctness proofs of non-trivial C programs according to the operational semantics of C defined in CompCer
High-order Large Eddy Simulations of Confined Rotor-Stator Flows

International audienceIn many engineering and industrial applications, the investigation of rotating turbulent flow is of great interest. In rotor-stator cavities, the centrifugal and Coriolis forces have a strong influence on the turbulence by producing a secondary flow in the meridian plane composed of two thin boundary layers along the disks separated by a non-viscous geostrophic core. Most numerical simulations have been performed using RANS and URANS modelling, and very few investigations have been performed using LES. This paper reports on quantitative comparisons of two high-order LES methods to predict a turbulent rotor-stator flow at the rotational Reynolds number Re=400000. The classical dynamic Smagorinsky model for the subgrid-scale stress (Germano et al., Phys Fluids A 3(7):1760-1765, 1991) is compared to a spectral vanishing viscosity technique (Séverac & Serre, J Comp Phys 226(2):1234-1255, 2007). Numerical results include both instantaneous data and postprocessed statistics. The results show that both LES methods are able to accurately describe the unsteady flow structures and to satisfactorily predict mean velocities as well as Reynolds stress tensor components. A slight advantage is given to the spectral SVV approach in terms of accuracy and CPU cost. The strong improvements obtained in the present results with respect to RANS results confirm that LES is the appropriate level of modelling for flows in which fully turbulent and transition regimes are involved
Polishing of synthetic electroplating wastewater in microcosm upflow constructed wetlands: Metals removal mechanisms

International audienceThis paper presents the study of the metals removal mechanisms in microcosm upflow constructed wetlands used for polishing of synthetic electroplating wastewater. Four types of columns were used: with and without plants and with different bed media (peat or gravel). The main design goal of the columns with peat was to promote precipitation of metals with biogenic sulfides produced by sulfate-reducing bacteria. The feed of the system contained mainly Cu, Ni, Pb, Zn, sulfates and cyanides. The substrate from the microcosm was sampled after cessation of the experiment (53 weeks) from the bottom and top layers of selected columns and was analyzed using sequential extraction procedure and scanning electron microscopy-energy-dispersive X-ray spectroscopy method. Additionally, solids retained on filter surface after filtering water samples withdrawn from the water layer covering the bed media in selected columns were analyzed by the latter method. The obtained results showed that the intended process for metals removal, which was precipitation of metal sulfides, was responsible for binding only a minor fraction of metals. The major portion of metals was present as exchangeable and reducible fraction. The presented study suggests that the onset of the conditions favorable for precipitation of sulfides may not occur during short-term experiment. It may stem from the specific characteristics of the experiment. It is suggested that short-term studies should not be extrapolated to predict long-term behavior of the system
Nuclear magnetic relaxation dispersion investigations of water retention mechanism by cellulose ethers in mortars

International audienceWe show how nuclear magnetic spin-lattice relaxation dispersion of proton-water (NMRD) can be used to elucidate the effect of cellulose ethers on water retention and hydration delay of freshly-mixed white cement pastes. NMRD is useful to determine the surface diffusion coefficient of water, the specific area and the hydration kinetics of the cement-based material. In spite of modifications of the solution's viscosity, we show that the cellulosic derivatives do not modify the surface diffusion coefficient of water. Thus, the mobility of water present inside the medium is not affected by the presence of polymer. However, these admixtures modify significantly the surface fraction of mobile water molecules transiently present at solid surfaces. This quantity measured, for the first time, for all admixed cement pastes is thus relevant to explain the water retention mechanism
Vent sizing: Analysis of the blowdown of a hybrid non tempered system

International audienceThe runaway and blowdown of a non tempered hybrid chemical system (30% cumene hydroperoxide) exposed to an external heat input was investigated using a 0.1 l scale tool. The maximum temperature and the maximum temperature rise rate were showed to be sensitive to the vent size. An Antoine type correlation between the maximum temperatures and pressures was observed. These resulted from the presence of vapour, mainly generated by the reaction products. Increasing the initial filling ratio resulted in an earlier vent opening but did not have a significant influence on the blow-down. Three types of mass venting behaviour were observed, when changing the vent area to volume ratio (A/V): * for large A/V, two-phase venting occurred from the vent opening until the end of the second pressure peak; * for medium A/V, two-phase venting occurred before and after the turnaround. The data seem to indicate that gas only venting occurred at turn-around; * for low A/V, two-phase venting was observed only after the second pressure peak. Two-phase venting after the second pressure peak probably results from the boiling of the hot reaction products at low pressure
The Last Termination in the South Indian Ocean: A unique terrestrial record from Kerguelen Islands (49°S) situated within the Southern Hemisphere westerly belt

International audienceThe awareness of the significance of the Southern Ocean in the Earth's climate system has become increasingly obvious. The deglacial atmospheric CO2 rise during warming periods in Antarctica has been attributed to CO2 ventilation from the deep ocean caused by enhanced upwelling around the Antarctic Divergence. It has been hypothesized that, more intense Southern Hemisphere westerly winds aligned with the Antarctic Circumpolar Current due to a southward shift of the wind belt from its Last Glacial Maximum equator-ward position, are the main drivers. Reconstructions of past changes in atmospheric circulation in the Southern Hemisphere are still scarce and the overall picture is patchy with sometimes contradictory results. For obvious reasons, most terrestrial records originate from southern South America and New Zealand. Here we present a terrestrial record from the Indian sector of the Southern Ocean, from Kerguelen Islands located at 49°S. A peat record is investigated using a multi-proxy approach (pollen and plant macrofossils, magnetic susceptibility, XRF analyses, biogenic silica content, Rock-Eval6 analysis and humification degree). Peat accumulation starts at about 16,000 cal yr BP with relatively warm and dry conditions. The most prominent change in our proxy data occurs at 13,600 cal yr BP, when peat ponds were established on the peat surface, resulting in lacustrine-type deposits, as a result of very high humidity, and with proxies implying very windy conditions. Within chronological uncertainties, this onset coincides with the onset of the so-called Oceanic Cold Reversal, based on the deuterium excess data in the EPICA Dome C ice core record. Kerguelen Islands are located in the moisture source area of Dome C and a change in atmospheric circulation at that time could explain both records. Around 12,900 cal yr BP, at the end of the Antarctic Cold Reversal, pond/lake sediments give way to more peaty deposits, with proxies suggesting slightly drier, less windy and probably warmer conditions. Kerguelen Islands became less influenced by the Southern Hemisphere westerly winds and these conditions were amplified during the early Holocene climate optimum as found in Antarctic ice core records
Role of the basin boundary conditions in gravity wave turbulence

International audienceGravity wave turbulence is studied experimentally in a large wave basin where irregular waves are generated unidirectionally. The role of the basin boundary conditions (absorbing or reflecting) and of the forcing properties are investigated. To that purpose, an absorbing sloping beach opposite to the wavemaker can be replaced by a reflecting vertical wall. We observe that the wave field properties depend strongly on these boundary conditions. Quasi-one dimensional field of nonlinear waves propagate before to be damped by the beach whereas a more multidirectional wave field is observed with the wall. In both cases, the wave spectrum scales as a frequency-power law with an exponent that increases continuously with the forcing amplitude up to a value close to -4, which is the value predicted by the weak turbulence theory. The physical mechanisms involved are probably different according to the boundary condition used, but cannot be easily discriminated with only temporal measurements.  We have also studied freely decaying gravity wave turbulence in the closed basin. No self-similar decay of the spectrum is observed, whereas its Fourier modes decay first as a time power law due to nonlinear mechanisms, and then exponentially due to linear viscous damping. We estimate the linear, nonlinear and dissipative time scales to test the time scale separation that highlights the important role of a large scale Fourier mode. By estimation of the mean energy flux from the initial decay of wave energy, the Kolmogorov-Zakharov constant is evaluated and found to be compatible with a recent theoretical value
Viewing another person's body as a target object: a behavioural and PET study of pointing.
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Pointing at a person's body

International audienceHumans usually point at objects to communicate with other persons, although they generally avoid pointing at the other's body. Moreover, patients with heterotopagnosia after left parietal damage cannot point at another person's body parts, although they can point at objects and at their own body parts and although they can grasp the others' body parts. Strikingly, their performance gradually improves for figurative human body targets. Altogether, this suggests that the body of another real person holds a specific status in communicative pointing. Here, we test in healthy individuals whether performance for communicative pointing is influenced by the communicative capacity of the target. In Experiment 1, pointing at another real person's body parts was compared to pointing at objects, and in Experiment 2, the person was replaced by a manikin. While reaction times for pointing at objects were shorter compared to pointing at other person's body parts, they were similar for objects and manikin body parts. By adapting Experiment 1 to PET-scan imaging (Experiment 3), we showed that, compared to pointing at objects, the brain network for pointing at other person's body parts involves the left posterior intraparietal sulcus, lesion of which could cause heterotopagnosia. Taken together, our results indicate that the specificity of pointing at another person's body goes beyond the visuo-spatial features of the human body and might rather rely on its communicative capacity
3D FEM simulation of the flow forming process using Lagrangian and ALE methods

Reprinted with permission from AIP Conf. Proc.May 17, 2007 -- Volume 908, pp. 257-262 MATERIALS PROCESSING AND DESIGN; Modeling, Simulation and Applications; NUMIFORM '07; Proceedings of the 9th International Conference on Numerical Methods in Industrial Forming Processes; doi:10.1063/1.2740821 Copyright 2007 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of PhysicsInternational audienceThe process of flow forming is numerically modeled using finite element codes based on the Forge2005® software. Two numerical approaches are considered. The first one uses an updated Lagrangian formulation. The problem is solved with help of a self-contact management algorithm. The second approach consists in using an ALE formulation that permits to optimize meshing with an adaptive method based on the Zienkiewicz-Zhu error estimation. The ALE method is well adapted to incremental forming processes such as flow forming and allows dealing with difficulties generated by the contact between the work piece and tools. Both formulations are coupled with complex tool kinematics. The Lagrangian formulation gives realistic results. The ALE formulation is promising with regard to computational time, and simulations on simple configurations show fairly good agreements with Lagrangian results
Diagenetic modulation of the magnetic properties in sediments from the Northern Indian Ocean

International audience[1] Large changes in magnetic mineral concentration dependent parameters by more than 1 order of magnitude occur over 50–150 cm intervals in two marine sediment cores from the oxygen minimum zone in the Gulf of Aden. High-resolution sedimentological and chemical analyses indicate that these intervals are not associated with turbiditic events or sediment reworking, they do not result from changes in carbonate dilution or differences in sediment properties, and they do not correspond to volcanic layers. Magnetic mineralogical analyses reveal a change in magnetic mineral concentration from a magnetite-goethite assemblage to pure magnetite within the peak. The peaks almost disappear when the abundance of magnetic minerals is calculated after correcting for the magnetic moments of each magnetic mineral. Therefore, under the assumption that the variability of the magnetic parameters results from postdepositional mineralogical transformations, a relatively constant amount of magnetite was present at the surface of the sediment. Changes in redox conditions and nonsteady state diagenesis transformations have effectively been observed along both cores. Large values of total organic carbon coincide with poor preservation of biogenic and detrital magnetite, which reflects reductive dissolution of the finer magnetite grains. At the same levels, Fe 2þ release from reductively dissolved magnetite favored precipitation of goethite. The susceptibility peaks coincide with episodes of magnetite preservation caused by reduced surfac