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One timeless challenge in rock magnetic studies, inclusive of paleomagnetism and environmental magnetism, is decomposing a sample's bulk magnetic behavior into its individual magnetic mineral components. We present a method permitting to decompose the magnetic behavior of a bulk sample experimentally and at low temperature avoiding any ambiguities in data interpretation due to heating-induced alteration. A single instrument is used to measure the temperature dependence of remanent magnetizations and to apply an isothermal demagnetization step at any temperature between 2 and 400 K. The experimental method is validated on synthetic mixtures of magnetite, hematite, goethite as well as on natural loess samples where the contributions of magnetite, goethite, hematite and maghemite are successfully isolated. The experimental protocol can be adapted to target other iron bearing minerals relevant to the rock or sediment under study. One limitation rests on the fact that the method is based on remanent magnetizations. Consequently, a quantitative decomposition of absolute concentration of individual components remains unachievable without assumptions. Nonetheless, semi-quantitative magnetic mineral concentrations were determined on synthetic and natural loess/paleosol samples in order to validate and test the method as a semi-quantitative tool in environmental magnetism studies.

Base de données aérodynamique; Acoustic signal of speech sounds is underlain by aerodynamic principles. The Aerodynamics of speech contributes to the mechanistic explanations of speech production. This database was designed during an ARC project ”Dynamique des syste`mes phonologiques” in which the study of aerodynamic constraints on speech was an important target. Data were recorded between 1996 and 1999 at the Erasmus Hospital (Hôpital Erasme) of Université Libre de Bruxelles. The goal was to obtain a substantial amount of data with simultaneous recording, in various context, of the speech acoustic signal, subglottal pressure (Ps), intraoral pressure (Po), oral airflow (Qo) and nasal airflow (Qn). This database contains recordings of 2 English, 1 Amharic, and 7 French speakers and is provided with data conversion and visualisation tools. Another aim of this project was to obtain some reference values of the aerodynamics of speech production for female and male speakers uttering different types of segments and sentences in French.

Magnetic properties coupled with sortable silt are investigated for Holocene marine sedimentary sequences located in the subpolar North Altantic, in the Charlie– Gibbs fracture zone (53°N) and in central (57°N) and southern Gardar drift (59°N). All the cores are located at water depths bathed by the Iceland–Scotland Overflow Water, mixed at the southernmost locality with southern sourced water masses. The goal of the multi-proxy study is the changes in the dynamics and the properties of bottom water mass during Holocene. After checking that the magnetic minerals is magnetite of uniform grain size, the low field magnetic susceptibility is used as a magnetic concentration parameter and as a tracer of the transport efficiency by the bottom current from the northern basaltic-derived source. The mean sortable silt size is used as a tracer of bottom current strength whatever the detrital source.

autoSSA algorithm which allows an unsupervised usage of the singular spectrum analysis (SSA).

URL des Documents de travail : http://ces.univ-paris1.fr/cesdp/cesdp2016.html; Documents de travail du Centre d'Economie de la Sorbonne 2016.38 - ISSN : 1955-611X; We consider a model of opinion formation based on aggregation functions. Each player modifies his opinion by arbitrarily aggregating the current opinion of all players. A player is influential for another player if the opinion of the first one matters for the latter. A generalization of influential player to a coalition whose opinion matters for a player is called influential coalition. Influential players (coalitions) can be graphically represented by the graph (hypergraph) of influence, and the convergence analysis is based on properties of the hypergraphs of influence. In the paper, we focus on the practical issues of applicability of the model w.r.t. the standard opinion formation framework driven by the Markov chain theory. For the qualitative analysis of convergence, knowing the aggregation functions of the players is not required, but one only needs to know the influential coalitions for every player. We propose simple algorithms that permit to fully determine the influential coalitions. We distinguish three cases: the symmetric decomposable model, the anonymous model, and the general model.; Nous considérons un modèle de formation d'opinion basé sur les fonctions d'agrégation. Chaque agent modifie son opinion en agrégeant de manière arbitraire l'opinion des autres agents. Un agent est influent pour un autre agent si l'opinion du premier compte pour ce dernier. Une généralisation de la notion d'agent influent mène à la notion de coalition influente pour un agent. Les agents (coalitions) influents peuvent être représentés graphiquement par un graphe d'influence (hypergraphe d'influence), et l'analyse de la convergence du modèle est basée sur les propriétés des hypergraphes d'influence. Dans l'article, nous nous focalisons sur les aspects pratiques d'applicabilité du modèle par rapport au cadre standard de formation d'opinion régi par une chaîne de Markov. Il n'est pas nécessaire de connaître les fonctions d'agrégation pour l'analyse qualitative de la convergence, pour laquelle la connaissance des coalitions influentes suffit. Nous proposons des algorithmes simples qui permettent de déterminer complètement les coalitions influentes. Nous distinguons trois cas : le modèle décomposable symétrique, le modèle anonyme et le modèle général.

URL des Documents de travail : https://centredeconomiesorbonne.cnrs.fr; Documents de travail du Centre d'Economie de la Sorbonne 2020.27 - ISSN : 1955-611X; It has been claimed that climate policies can be evaluated by the Pareto principle. However, climate policies lead to different identities and different numbers of future people. Even if one assumes that the number of future people is countably infinite independently of policy choice, the problem is that there exists no natural one-to-one correspondence between the components of the compared alternatives. This non-existence means that the components of streams are indexed by natural numbers that do not correspond to particular people, making a case for impartiakity in the sense of Strong anonymity. Strong anonymity is incompatible with Strong Pareto. The paper re-examines this incompatibility and investigates how far sensitivity for the well-being at any one component can be extended without contradicting Strong anonymity. We show that Strong anonymity combined with four rather innocent axioms has two consequences: (i) There can be sensitivity for the well-being at a particular component of the stream if and only if a finite set of people have higher well-beings, and (ii) adding people to the population cannot have positive social value.

Article published in the proceedings of the C2SI conference, May 2015.; Pairings are mathematical tools that have been proven to be very useful in the construction of many cryptographic protocols. Some of these protocols are suitable for implementation on power constrained devices such as smart cards or smartphone which are subject to side channel attacks. In this paper, we analyse the efficiency of the point blinding countermeasure in pairing based cryptography against side channel attacks. In particular,we show that this countermeasure does not protect Miller's algorithm for pairing computation against fault attack. We then give recommendation for a secure implementation of a pairing based protocol using the Miller algorithm.

We study the concept of compactor, which may be seen as a counting-analogue of kernelization in counting parameterized complexity. For a function F:Sigma^* -> N and a parameterization kappa: Sigma^* -> N, a compactor (P,M) consists of a polynomial-time computable function P, called condenser, and a computable function M, called extractor, such that F=M o P, and the condensing P(x) of x has length at most s(kappa(x)), for any input x in Sigma^*. If s is a polynomial function, then the compactor is said to be of polynomial-size. Although the study on counting-analogue of kernelization is not unprecedented, it has received little attention so far. We study a family of vertex-certified counting problems on graphs that are MSOL-expressible; that is, for an MSOL-formula phi with one free set variable to be interpreted as a vertex subset, we want to count all A subseteq V(G) where |A|=k and (G,A) models phi. In this paper, we prove that every vertex-certified counting problems on graphs that is MSOL-expressible and treewidth modulable, when parameterized by k, admits a polynomial-size compactor on H-topological-minor-free graphs with condensing time O(k^2n^2) and decoding time 2^{O(k)}. This implies the existence of an FPT-algorithm of running time O(n^2 k^2)+2^{O(k)}. All aforementioned complexities are under the Uniform Cost Measure (UCM) model where numbers can be stored in constant space and arithmetic operations can be done in constant time.

Thanks to its optimal location on the northern Brazilian margin, core MD09-3257 records both ocean circulation and atmospheric changes. The latter occur locally in the form of increased rainfall on the adjacent continent during the cold intervals recorded in Greenland ice and northern North Atlantic sediment cores (i.e., Greenland stadials). These rainfall events are recorded in MD09-3257 as peaks in ln(Ti ∕ Ca). New sedimentary Pa ∕ Th data indicate that mid-depth western equatorial water mass transport decreased during all of the Greenland stadials of the last 40 kyr. Using cross-wavelet transforms and spectrogram analysis, we assess the relative phase between the MD09-3257 sedimentary Pa ∕ Th and ln(Ti ∕ Ca) signals. We show that decreased water mass transport between a depth of ∼1300 and 2300 m in the western equatorial Atlantic preceded increased rainfall over the adjacent continent by 120 to 400 yr at Dansgaard–Oeschger (D–O) frequencies, and by 280 to 980 yr at Heinrich-like frequencies. We suggest that the large lead of ocean circulation changes with respect to changes in tropical South American precipitation at Heinrich-like frequencies is related to the effect of a positive feedback involving iceberg discharges in the North Atlantic. In contrast, the absence of widespread ice rafted detrital layers in North Atlantic cores during D–O stadials supports the hypothesis that a feedback such as this was not triggered in the case of D–O stadials, with circulation slowdowns and subsequent changes remaining more limited during D–O stadials than Heinrich stadials.

Reproduction pipeline and necessary data for Sections 7.3 and 3.4 of Bacon et al., (2017) and Inami et al., (2017) respectively (papers I and II of the series of papers on "The MUSE Hubble Ultra Deep Field Survey", published in Astronomy & Astrophysics, 608, A1 and A2). This pipeline will estimate the Hubble Space Telescope (HST) segmentation maps (for paper 1) and make the necessary measurements (for paper 2) for objects that were detected in the MUSE 3D cubes, but didn't correspond to any detection in the Rafelski et al. (2015) catalog. This repository on Zenodo contains all the necessary input data, software and reproduction pipeline (containing the scripts, configuration files and settings to exactly reproduce the results in Sections 7.3 and 3.4 of the papers above). Below is a description of the contents: gnuastro-0.2.51-bc64-bugfix.tar.gz: Gnuastro version 0.2.51 with a small bug fix only relevant to this analysis. The base Gnuastro 0.2.51 was used for this pipeline when it was written, similar to zenodo.1163746. However, a bug relating to estimation of upper-limit magnitudes was later found. This bug was fixed, but along with many other changes that made the whole Gnuastro package incompatible with this pipeline. Hence, this bug-fixed copy of Gnuastro 0.2.51 was used in the catalog of Inami et al. (2017). The reproduction pipeline below contains the fixed file and instructions on how to make this version from version 0.2.51 that is available in the official Gnuastro version controlled history. The library dependencies of this version of Gnuastro can be downloaded from zenodo.1163746 (gnuastro-dependencies.tar.gz). IMPORTANT NOTE: Since version 0.2.51 of Gnuastro was released, CFITSIO (one of Gnuastro's dependencies) has added a dependency for the cURL library (to read https URLs). Therefore, to install Gnuastro 0.2.51, please install CFITSIO version 3.41 or earlier. hst-uvudf.tar.gz: images and weight maps in 0.06 arcsec/pixel resolution from the HST-UVUDF survey. These images are not necessary to run the reproduction pipeline (they will be downloaded from the HST archives if not present). They are stored here for the self-sufficiency of this repository and faster download: in this lossless compressed format, they are roughly 1/4th the volume of the same files in HST archives. hst-xdf.tar.gz: images and weight maps in 0.06 arcsec/pixel resolution from the HST-XDF survey. These are also available from the HST archives and are kept here with similar reasons to above (with a compression ratio of almost 1/3rd). output-v4-2-gf97e.tar.gz: output of the reproduction pipeline. reproduce-v4-2-gf97e.tar.gz: The reproduction pipeline (version 4-2-gf97e) that produces the results (tables) plotted in the paper. The full Git version controlled history of this repository is available on git-cral.univ-lyon1.fr or gitlab.com. We recommend cloning from the Git repository if it is available. This tarball is kept here in case those servers don't work or Git is no longer in common use. Please see the README file in this repository for instructions on how to run the reproduction pipeline and exactly reproduce the results. This pipeline will download all the necessary data if they aren't already present on the system (it is probably just necessary to install the required version of Gnuastro). The Creative Commons Attribution-NonCommercial 4.0 copyright mentioned in the Zenodo webpage is only applicable to files that don't have an explicit copyright within them. The copyright of other files (mainly scripts and software) is mentioned within them (all are free licenses). For any issues with the pipeline/processing, please contact Mohammad Akhlaghi. {"references": ["Illingworth et al. (2013), Astrophysical Journal Supplement, Volume 209, Issue 1, article id. 6", "Rafelski et al. (2015), Astronomical Journal, Volume 150, Issue 1, article id. 31"]}