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141.
From technical and industrial heritage, curators are in charge of numerous and important collections of metallic items which
are representative of the industrial and technical development of our societies. The diagnosis of the conservation state and
the choice of the restoration treatment are important questions that have to be solved by curators to avoid expensive restoration
works. This paper proposes to show how simple electrochemical techniques can be used as an efficient tool to contribute to
the diagnosis of the conservation state of metallic artefacts and to monitor the restoration treatment through three examples.
In the case of the very-corroded aluminium alloys of aircraft belonging to the Air and Space Museum (Le Bourget, France),
stationary electrochemical measurements are able to characterise the allowable electrochemical effect of thick corrosion layer
on the corrosion rate of metal but are not sufficient to give a complete diagnosis. In contrary, for the bronze part of the
miner's lamp collection of the Mining History Centre of Lewarde, France and the nickel-plated steel of an ancient typewriter
of the Musée des Arts et Metiers, Paris, France, an inhibition treatment based on sodium carboxylate within the framework
of temporary conservation treatment was applied with success, on the basis of the electrochemical results obtained in the
present study. 相似文献
142.
Compact cancer biomarkers discovery using a swarm intelligence feature selection algorithm 总被引:1,自引:0,他引:1
Biomarker discovery is a typical application from functional genomics. Due to the large number of genes studied simultaneously in microarray data, feature selection is a key step. Swarm intelligence has emerged as a solution for the feature selection problem. However, swarm intelligence settings for feature selection fail to select small features subsets. We have proposed a swarm intelligence feature selection algorithm based on the initialization and update of only a subset of particles in the swarm. In this study, we tested our algorithm in 11 microarray datasets for brain, leukemia, lung, prostate, and others. We show that the proposed swarm intelligence algorithm successfully increase the classification accuracy and decrease the number of selected features compared to other swarm intelligence methods. 相似文献
143.
Nathalie Dupré Pauline Rémy Dr. Kévin Micoine Dr. Cécile Boglio Dr. Serge Thorimbert Dr. Emmanuel Lacôte Dr. Bernold Hasenknopf Prof. Max Malacria Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(24):7256-7264
The preparation of new organosoluble Lewis acidic polyoxometalates (POMs) is reported. These complexes were prepared by the incorporation of Zr, Sc, and Y atoms into the corresponding monolacunary Dawson [P2W17O61]10? and Keggin [PW11O39]7? polyoxotungstates. The catalytic activity of these compounds was evaluated for C? C bond formation in the Diels–Alder, Mannich, and Mukaiyama‐type reactions. Comparisons with previously described Lewis acidic POMs are reported. Competitive reactions between imines and aldehydes or between various imines demonstrated that fine tuning of the reactivity could be reached by varying the metal atom incorporated into the polyanionic framework. A series of experiments that employed pyridine derivatives allowed us to distinguish between the Lewis and induced Brønsted acidity of the POMs. These catalysts activate imines in a Lewis acidic way, whereas aldehydes are activated by indirect Brønsted catalysis. 相似文献
144.
A nontomography approach for the measurement of angular-dependent coherent-scatter cross section of x rays (E?40-80 keV) is described. It is shown that an analyzer crystal, which is proposed to be used for the sampling of the cross section, simultaneously provides information about the location of the scattering volume inside the object. A numerical simulation demonstrates that this method can be applied for nondestructive analysis of an object's internal structure. 相似文献
145.
We investigate thermal inflation in double-screen entropic cosmology. We find that its realization is general, resulting from the system evolution from non-equilibrium to equilibrium. Furthermore, going beyond the background evolution, we study the primordial curvature perturbations arising from the universe interior, as well as from the thermal fluctuations generated on the holographic screens. We show that the power spectrum is nearly scale-invariant with a red tilt, while the tensor-to-scalar ratio is in agreement with observations. Finally, we examine the non-Gaussianities of primordial curvature perturbations, and we find that a sizable value of the non-linearity parameter is possible due to holographic statistics on the outer screen. 相似文献
146.
147.
We derive expansion results in order to approximate the law of the average of the marginal of diffusion processes. The average is computed w.r.t. a general parameter that is involved in the diffusion dynamics. Our approximation is based on the use of proxys with normal distribution or log-normal distribution, so that the expansion terms are explicit. We provide non asymptotic error bounds, which justifies the expansion accuracy as the time or the diffusion coefficients are small in a suitable sense. 相似文献
148.
Guy Barles Emmanuel Chasseigne Adina Ciomaga Cyril Imbert 《Calculus of Variations and Partial Differential Equations》2014,50(1-2):283-304
In this paper, we study the large time behavior of solutions of a class of parabolic fully nonlinear integro-differential equations in a periodic setting. In order to do so, we first solve the ergodic problem (or cell problem), i.e. we construct solutions of the form $\lambda t + v(x).$ We then prove that solutions of the Cauchy problem look like those specific solutions as time goes to infinity. We face two key difficulties to carry out this classical program: (1) the fact that we handle the case of “mixed operators” for which the required ellipticity comes from a combination of the properties of the local and nonlocal terms and (2) the treatment of the superlinear case (in the gradient variable). Lipschitz estimates previously proved by the authors (2012) and Strong Maximum principles proved by the third author (2012) play a crucial role in the analysis. 相似文献
149.
Emmanuel N. Barron 《Comptes Rendus Mathematique》2013,351(19-20):737-741
The main theorem connecting convex Hamiltonians and semicontinuous viscosity solutions due to Barron and Jensen is extended to quasiconvex Hamiltonians. Some applications are indicated. 相似文献
150.
Diederik Aerts Bart D’Hooghe Emmanuel Haven 《International Journal of Theoretical Physics》2010,49(12):2971-2990
We prove a theorem which shows that a collection of experimental data of probabilistic weights related to decisions with respect
to situations and their disjunction cannot be modeled within a classical probabilistic weight structure in case the experimental
data contain the effect referred to as the ‘disjunction effect’ in psychology. We identify different experimental situations
in psychology, more specifically in concept theory and in decision theory, and in economics (namely situations where Savage’s
Sure-Thing Principle is violated) where the disjunction effect appears and we point out the common nature of the effect. We
analyze how our theorem constitutes a no-go theorem for classical probabilistic weight structures for common experimental
data when the disjunction effect is affecting the values of these data. We put forward a simple geometric criterion that reveals
the non classicality of the considered probabilistic weights and we illustrate our geometrical criterion by means of experimentally
measured membership weights of items with respect to pairs of concepts and their disjunctions. The violation of the classical
probabilistic weight structure is very analogous to the violation of the well-known Bell inequalities studied in quantum mechanics.
The no-go theorem we prove in the present article with respect to the collection of experimental data we consider has a status
analogous to the well known no-go theorems for hidden variable theories in quantum mechanics with respect to experimental
data obtained in quantum laboratories. Our analysis puts forward a strong argument in favor of the validity of using the quantum
formalism for modeling the considered psychological experimental data as considered in this paper. 相似文献