1,853 research outputs found

    RBF neural net based classifier for the AIRIX accelerator fault diagnosis

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    The AIRIX facility is a high current linear accelerator (2-3.5kA) used for flash-radiography at the CEA of Moronvilliers France. The general background of this study is the diagnosis and the predictive maintenance of AIRIX. We will present a tool for fault diagnosis and monitoring based on pattern recognition using artificial neural network. Parameters extracted from the signals recorded on each shot are used to define a vector to be classified. The principal component analysis permits us to select the most pertinent information and reduce the redundancy. A three layer Radial Basis Function (RBF) neural network is used to classify the states of the accelerator. We initialize the network by applying an unsupervised fuzzy technique to the training base. This allows us to determine the number of clusters and real classes, which define the number of cells on the hidden and output layers of the network. The weights between the hidden and the output layers, realising the non-convex union of the clusters, are determined by a least square method. Membership and ambiguity rejection enable the network to learn unknown failures, and to monitor accelerator operations to predict future failures. We will present the first results obtained on the injector.Comment: 3 pages, 4 figures, LINAC'2000 conferenc

    Un nuevo Eurydema Lp. ibérico (Heteroptera, Pentatomidae)

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    The Dynamic Formation of Prominence Condensations

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    We present simulations of a model for the formation of a prominence condensation in a coronal loop. The key idea behind the model is that the spatial localization of loop heating near the chromosphere leads to a catastrophic cooling in the corona (Antiochos & Klimchuk 1991). Using a new adaptive grid code, we simulate the complete growth of a condensation, and find that after approx. 5,000 s it reaches a quasi-steady state. We show that the size and the growth time of the condensation are in good agreement with data, and discuss the implications of the model for coronal heating and SOHO/TRACE observations.Comment: Astrophysical Journal latex file, 20 pages, 7 b-w figures (gif files

    On the novel free porphyrins corallistin B, C, D, and E : isolation from the demosponge Corallistes sp. of the Coral Sea and reactivity of their nickel (2) complexes toward formylating reagents

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    Reported here are the novel free corallistin B, C, D, and E, isolated as methyl esters 2a, 3a, 4a, and 5a, respectively, from the sponge #Corallistes sp.(#Lithistida) collected at the basis of the South New Caledonian coral reef. A protocol is also established for formulation of their NiII complexes, which show a different reactivity pattern toward DMF/POCI3 from metal complexes of deuteroporphyrin IX (isolate as 6a) also present in the sponge, the new corallistins, which may be thought to derive from protoporphyrin via heme, account for an amazing 60% of the etOH extract from the sponge. (Résumé d'auteur

    Differential rotation and meridional flow in the solar supergranulation layer: Measuring the eddy viscosity

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    We measure the eddy viscosity in the outermost layers of the solar convection zone by comparing the rotation law computed with the Reynolds stress resulting from f-plane simulations of the angular momentum transport in rotating convection with the observed differential rotation pattern. The simulations lead to a negative vertical and a positive horizontal angular momentum transport. The consequence is a subrotation of the outermost layers, as it is indeed indicated both by helioseismology and the observed rotation rates of sunspots. In order to reproduce the observed gradient of the rotation rate a value of about 1.5 x 10^{13} cm/s for the eddy viscosity is necessary. Comparison with the magnetic eddy diffusivity derived from the sunspot decay yields a surprisingly large magnetic Prandtl number of 150 for the supergranulation layer. The negative gradient of the rotation rate also drives a surface meridional flow towards the poles, in agreement with the results from Doppler measurements. The successful reproduction of the abnormally positive horizontal cross correlation (on the northern hemisphere) observed for bipolar groups then provides an independent test for the resulting eddy viscosity.Comment: 6 pages, 8 figures, Astronomy and Astrophysics (subm.

    Evaluation of emotional education in the middle cycle of Primary School

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    El principal propósito de la educación consiste en favorecer el desarrollo integral de la persona, lo cual implica atender el aspecto cognitivo y afectivo. Tradicionalmente, se han priorizado sólo los contenidos cognitivos por este motivo queremos incidir sobre los afectos. El objetivo general de este trabajo de investigación que presentamos consiste en aplicar y evaluar un Programa de Educación Emocional (PEEP), integrado dentro del currículum de Primaria de ciclo medio que ayude a prevenir los efectos nocivos de las emociones negativas y facilite la relación consigo mismo y con los demás. Objetivo general que se constatara a partir de cuatro criterios: conseguir un mejor conocimiento de las propias emociones y de las emociones de los demás, desarrollar estrategias de regulación emocional, mejorar la autoestima, aprender habilidades de vida y socioemocionales. Pues, la finalidad es intervenir en la mejora de la educación emocional de los alumnos entre los 8 y los 10 años, en total 510 alumnos de los cuales 104 formaron la muestra de investigación. Fueron divididos en dos grupos el grupo experimental y el grupo control, ambos constituían una muestra homogénea y estadísticamente comparable por lo que podíamos plantearnos una intervención y valorar su incidencia. Los resultados indican que mejora el nivel de Educación Emocional (EE) de estos alumnos con un nivel de significación de p= 0,001. A partir de este momento, podemos concretar que los resultados conseguidos por los alumnos que han seguido la aplicación del programa mejoran significativamente. Este resultado, nos permite afirmar que el uso intencional del programa de educación emocional para mejorar el ámbito afectivo ha incidido positivamente en el proceso de aprendizaje de los alumnos. Sin embargo consideramos esencial llevar a cabo una formación y posterior evaluación del profesorado en EE, como paso previo necesario para una aplicación óptima del programa.The main purpose of education is to favour overall personal development, which involves taking care of the cognitive aspect and the affective aspect of the self. Traditionally, the cognitive contents alone have taken priority, and it is for this reason that the authors have decided to underscore the affective facet. The main objective of the research project presented in this paper was to apply and evaluate an emotional education programme set up as an integrated part of the middle cycle (age 8 to 10) primary school curriculum to help prevent the injurious effects of negative emotions and facilitate students’ relationship with themselves and with others. Four criteria were established for finding this general objective: to obtain a better knowledge of one’s own emotions and others’ emotions, to develop emotional regulation strategies, to improve self-esteem and to learn life skills and socioemotional skills. The purpose was to take part in the improvement of the emotional education of students between 8 and 10 years of age. Out of a total of 510 students, 104 formed the sample. They were divided into two groups, the experimental group and the control group. Each constituted a homogenous, statistically comparable sample, thus enabling researchers to plan an intervention and weigh its effect. The results showed that the students’ emotional education level improved, with a significance level of p=0.001. The results obtained by the students who followed the programme improved significantly. This finding enables the authors to affirm that the intentional use of the emotional education programme to improve affective scope had a positive effect on the students’ learning process. However, the authors consider it essential to provide teachers with training in emotional education, followed by evaluation, as a prerequisite to optimal application of the programme

    Comparison of Lures Loaded with Codlemone and Pear Ester for Capturing Codling Moths, Cydia pomonella, in Apple and Pear Orchards using Mating Disruption

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    Studies were conducted in apple, Malus domestica Borkhausen and pear, Pyrus communis L. (Rosales: Rosaceae), orchards to evaluate the attractiveness of grey halobutyl septa loaded with 1 (L2) and 10 (Mega) mg of codlemone, 8E, 10E-dodecadien-1-ol, 3 mg of pear ester, ethyl (E,Z)-2,4-decadienoate (DA2313), and 3 mg of pear ester plus 3 mg of codlemone (Combo) to adult codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae). All studies were conducted in orchards treated with pheromone mating disruption. All four lures were tested on diamond-shaped sticky traps placed in 60 plots of apple and 40 plots of pears in 2003/04, and in 62 plots of apples and 30 of pears in 2004–05. Combo lures attracted significantly more moths (males + females) than all the others in both years. Comparisons among flights showed significant differences mainly for flight 1 and 2, but not always for flight 3. Mega lures provided no significant improvement compared with L2 lures during both seasons regarding the total number of moths. Combo and DA2313 lures attracted fewer females than males during the whole season. For most sample dates, more virgin than mated females were attracted to Combo lures, except during the third flight, and the overall ratio was 60:40, although the difference was not statistically significant. We conclude that the Combo lures are better indicators of codling moth activity in pheromone treated orchards, regardless of pest population level, when compared with similar lures containing codlemone or pear ester alone
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