864 research outputs found

    Modeling of the Electrochemical Reactions at the Electrode-Electrolyte Interface of Nickel/Metal Hydride Batteries by an Equivalent Electrical Circuit

    Get PDF
    Based on the experimental impedance spectra, the electrochemical reactions that are deposed at the electrode-electrolyte interface can be modeled by equivalent electrical circuits. Each element used in the circuit must have a physical correspondence in the electrochemical system. In this work, a model has been proposed to a NiMH battery electrode to describe, in detail, the electrochemical process at the interface of this electrode. The theoretical impedance of a proposed circuit is a function of several variables. These adjusted variables to reach a good agreement between the theoretical spectra and the experimental spectra in the studied frequency. The Z-simplex software allows refining the experimental results. These results show a good superposition between the experimental spectra and the theoretical spectra corresponding to the proposed electric circuit. This leads to the conclusion that the proposed circuit describes the phenomena that take place at the interface of the hydride electrode

    Eliciting Gul’s Theory of Disappointment Aversion by the Tradeoff Method

    Get PDF
    Gul’s (1991) theory of disappointment aversion (DA) has several attractive features, being intuitive, analytically tractable, and parsimonious. In spite of this, the DA model has received little attention in practical applications, which may be partly due to the absence of a procedure to elicit the model. We show how the trade-off method, developed by Wakker and Deneffe (1996), can be used to elicit DA. Our elicitation method is parameter-free: it requires no assumption about utility and/or disappointment aversion. Quantitative tests of DA in three outcome domains, monetary gains, monetary losses, and life-years, suggest that the DA model is too parsimonious. Of the other models of disappointment aversion that have been proposed in the literature, our data are most consistent with the model of Loomes and Sugden (1986)

    Méningiome en plaque sphéno-orbitaire: à propos d’un cas avec revue de la littérature

    Get PDF
    Le méningiome intra osseux est une variété des méningiomes ectopiques dans lequel les cellules méningothéliales envahissent la paroi osseuse et entraînent une hyperostose. Le méningiome en plaque, variante macroscopique des méningiomes intra osseux, est une tumeur rare et survient fréquemment au niveau de la région sphéno-orbitaire ce qui le confond avec les tumeurs osseuses primitives. Nous rapportons le cas d'une patiente de 50 ans qui présente une exophtalmie avec cécité unilatérale gauche d'installation progressive depuis un an. L'examen trouve une exophtalmie axile, indolore et non réductible ainsi qu'une limitation de la motilité oculaire dans tous les sens du regard. La palpation montre une masse temporale gauche dure et adhérente à l'os. L'examen du fond d'oeil trouve un oedème papillaire gauche. Le scanner montre une lésion ostéocondensante temporo-sphéno-orbitaire gauche avec envahissement locorégional. Le diagnostic préopératoire fut une tumeur osseuse essentiellement maligne primitive ou secondaire. L'étude histologique a révélée un méningiome meningothélial de type en plaque. La patiente a bénéficié d'une exérèse avec reconstruction chirurgicale. Aucune récidive n'a été notée après 1 an de recul

    The use of reproductive vigor descriptors in studying genetic variability in nine Tunisian faba bean (Vicia faba L.) populations

    Get PDF
    A collection of nine Tunisian faba bean (Vicia faba) populations belonging to three botanical classes (Var. minor, var. equina and var. major) was evaluated using twenty seven agro-morphological traits. Analysis of variance, correlation coefficients and principal components analysis (PCA) were performed based on MVSP 3.13 program. Significant differences between populations were noted for most agromorphological traits in four main groups. The first group, positively correlated to the two axes, isrepresented by ‘Bachaar’ belonging to V. faba. var. minor, the second group, including V. faba. var. minor population (‘Massri’ and ‘Badï’), is positively correlated to the PC1 and negatively correlated to the PC2 while the third group, is composed of two V. faba var. major (‘Malti’ and ‘Batata’) and were positively and negatively correlated to the PC2 and PC1, respectively. Finally, the fourth group negatively correlated to the two axes, gathers the remaining population (‘Chahbi’, ‘Chemlali’, ‘Aguadulce’ and ‘Super Aguadulce’). The dendrogram based on Nei's genetic distance of the 9 populations using UPGMA method, show some genetic drift between populations.Key words: Faba bean, agromorphological traits, principal components analysis, UPGMA method

    Do financial professionals behave according to prospect theory? An experimental study

    Get PDF
    Prospect theory is increasingly used to explain deviations from the traditional paradigm of rational agents. Empirical support for prospect theory comes mainly from laboratory experiments using student samples. It is obviously important to know whether and to what extent this support generalizes to more naturally occurring circumstances. This article explores this question and measures prospect theory for a sample of private bankers and fund managers. We obtained clear support for prospect theory. Our financial professionals behaved according to prospect theory and violated expected utility maximization. They were risk averse for gains and risk seeking for losses and their utility was concave for gains and (slightly) convex for losses. They were also averse to losses, but less so than commonly observed in laboratory studies and assumed in behavioral finance. A substantial minority focused on gains and largely ignored losses, behavior reminiscent of what caused the current financial crisis

    A Tractable Method to Measure Utility and Loss Aversion under Prospect Theory

    Get PDF
    This paper provides an efficient method to measure utility under prospect theory, the most important descriptive theory of decision under uncertainty today. Our method is based on the elicitation of certainty equivalents for two-outcome prospects, a common way to measure utility. We applied our method in an experiment and found that most subjects were risk averse for gains and risk seeking for losses but had concave utility both for gains and for losses. This finding illustrates empirically that risk seeking and concave utility can coincide under prospect theory, a result that was derived theoretically by Chateauneuf and Cohen (1994). Utility was steeper for losses than for gains, which is consistent with loss aversion. Utility did not depend on the probability used in the elicitation, which offers support for prospect theory

    Transport électronique dans l’alliage liquide binaire Or–Argent

    Get PDF
    Electronic transport in liquid binary alloys Gold-SilverThe electrical resistivity of the liquid alloy Gold-Silver was measured on the totality of the diagram of phase since the melting point until 1150°C. Our measurements, made in a quartz cell equipped with tungsten electrodes, were compared with those obtained by Roll and Motz using a technique without electrodes. The  technique that we used does not reproduce the anomalies observed by Roll and Motz in the curves of resistivity and its temperature coefficient as function of the concentration. The confrontation of our experimental results with the theory was made by using two types of  dephasing as well as the pseudopotential suggested by Idress et al. and used by Alam and Tomak

    European training partnership for an inclusive society

    Get PDF
    The paper presents an European project aiming to consolidate the partners capacity of involving themselves actively in transitional partnership in order to promote the social inclusion of young instituonalized people in re-education centres by (i) increasing the institutional capacity of concurring at the reformation and the efficiency of the education and lifelong learning system in the detention and re-education centres for underage people and by (ii) professional and individual developing of the participants which can lead to local assumption of the reform

    Bilateral stellate neuroretinitis revealing a pheochromocytoma

    Get PDF
    Neuroretinitis (NR) is an inflammatory disorder characterized by optic disc  edema and subsequent formation of a macular star. We present a case of a 33 year old woman patient admitted for a progressive bilateral visual loss since two weeks. Fundus examination showed bilateral stellate neuroretinitis. Physical examination revealed a malignant hypertension of 210/150mmHg. Magnetic resonance imaging identified a left suprarenal mass, whereas urinary catecholamine level was abnormally high which supported a diagnosis of pheochromocytoma.The patient underwent a laparoscopic left suprarenal adrenalectomy after successful control of blood pressure. histopathologic examination confirmed the diagnosis of pheochromocytoma. Visual acuity was restored and the retinal alterations disappeared 7 months after surgery
    • …
    corecore