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1.
Asendorpf Jens B.; Warkentin Veronique; Baudonnière Pierre-Marie 《Canadian Metallurgical Quarterly》1996,32(2):313
Eighteen-month-old children were tested for mirror self-recognition using the classic rouge test or an alternative procedure, for social contingency awareness by being closely imitated for a long time, and for the capacity for communication by synchronic imitation. The classic mirror rouge test was shown to produce false negatives. Most recognizers and nonrecognizers became aware of being imitated and imitated the activity of a model, but only recognizers engaged in sustained synchronic imitation of the model. The results support our hypothesis that self-recognition and spontaneous perspective-taking develop in close synchrony because both require a capacity for secondary representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Jean-Denis Mathias Pierre-Marie Geffroy Jean-François Silvain 《Applied Thermal Engineering》2009,29(11-12):2391-2395
The aim of this paper is to provide a methodical approach for architectural optimization of power microelectronic devices. Because critical parameters of electronic devices are linked with reliability, architectural optimization, selection of the geometrical parameters of device and optimization of these parameters by iteration method associated by numerical analysis of reliability have to be achieved. In this way, this paper discusses about a methodical and numerical approach for the optimization of reliability in electronic devices, in particular the influence of geometrical parameters on the device reliability. 相似文献
3.
Earthquake Safety Evaluation of Gravity Dams Considering Aftershocks and Reduced Drainage Efficiency
This paper develops a methodology to perform seismic response analyses of concrete gravity dams considering aftershocks, and reduced drainage efficiency due to disruption of the drainage system. A database of earthquake records has been assembled to characterize main shocks and aftershocks. A drain finite difference hydraulic model considering laminar or turbulent two-dimensional flow in connecting cracks, geometrical distortions due to joint dilatancy while sliding, and misaligned drain segments is developed and validated. Coupled-hydromechanical analyses on the seismic response of a drained 90?m gravity dam are used to show the importance of cumulative displacements on the increase in uplift pressures, drain flow, and reduced sliding safety factors. Aftershock response is especially sensitive to the drainage system dimensions and model parameters, such as the foundation stiffness, and the number of potentially sliding joints. The proposed methodology forms the basis to develop displacement based performance criteria in stability evaluation of existing dams reevaluated for much higher ground motions intensities that they have been designed for many years ago. 相似文献
4.
Charmasson S Le Faouder A Loyen J Cosson RP Sarradin PM 《The Science of the total environment》2011,409(4):771-777
The hydrothermal deep-sea vent fauna is naturally exposed to a highly specific environment enriched in potentially toxic species such as sulfides, metals and natural radionuclides due to the convective seawater circulation inside the oceanic crust and its interaction with basaltic or ultramafic host rocks. However, data on radionuclides in biota from such environment are very limited. An investigation was carried out on tissue partitioning of 210Po and 210Pb, two natural radionuclides within the 238U decay chain, in Bathymodiolus azoricus specimens from the Mid-Atlantic Ridge (Menez Gwen field). These two elements showed different distributions with high 210Pb levels in gills and high 210Po levels in both gills and especially in the remaining parts of the body tissue (including the digestive gland). Various factors that may explain such partitioning are discussed. However, 210Po levels encountered in B. azoricus were not exceptionally high, leading to weighted internal dose rate in the range 3 to 4 μGy h− 1. These levels are slightly higher than levels characterizing coastal mussels (~ 1 μGy h− 1). 相似文献
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ASN.1 (Abstract Syntax Notation number One) is a standardized formal notation used to describe data exchanged between heterogeneous systems. An ASN.1 specification consists of modules which break down into formal definitions. When a protocol is updated, a new version of its ASN. 1 specification is produced. To keep interoperability between applications which support different versions of the same protocol, the specifier has to ensure that the new modules are compatible with the old ones. Our comparator, based on a complete formalization of comparison rules, can indicate the potential incompatibilities between ASN. 1:1997 specifications. 相似文献
7.
The preprocessing of large meshes to provide and optimize interactive visualization implies a complete reorganization that often introduces significant data growth. This is detrimental to storage and network transmission, but in the near future could also affect the efficiency of the visualization process itself, because of the increasing gap between computing times and external access times. In this article, we attempt to reconcile lossless compression and visualization by proposing a data structure that radically reduces the size of the object while supporting a fast interactive navigation based on a viewing distance criterion. In addition to this double capability, this method works out-of-core and can handle meshes containing several hundred million vertices. Furthermore, it presents the advantage of dealing with any n-dimensional simplicial complex, including triangle soups or volumetric meshes, and provides a significant rate-distortion improvement. The performance attained is near state-of-the-art in terms of the compression ratio as well as the visualization frame rates, offering a unique combination that can be useful in numerous applications. 相似文献
8.
Pierre-Marie Geffroy Merouane Lakehal Javier Goñi Eric Beaugnon Jean-Marc Heintz Jean-François Silvain 《Metallurgical and Materials Transactions A》2006,37(2):441-447
Magnetic molding technology is an original alternative process aimed at improving the metallurgical quality and dimensional
tolerances of the final components that are currently produced using the lost foam process. The initial development of the
magnetic molding process took place at the same time as the lost foam process, more than 30 years ago, but the magnetic moldin
process has never achieved the same level of industrial development. The purposes of this study are to introduce the magnetic
molding process and to define its advantages and characteristics. The comparative results obtained with both the lost foam
and the magnetic molding processes for aluminum casting are given. The main factors involved in the magnetic molding process
are also discussed. 相似文献
9.
Scheifler R Schwartz C Echevarria G DE Vaufleury A Badot PM Morel JL 《Environmental science & technology》2003,37(1):81-86
Isotopic dilution techniques were initially used to evaluate the bioavailability of trace metals contained in soils to plants, i.e., the phytoavailability. Here, we use for the first time an isotopic technique to evaluate the zooavailability of cadmium (Cd), i.e., the bioavailability to an animal organism. A terrestrial invertebrate, the snail Helix aspersa, was exposed for 14 days to a polluted soil that was spiked with 109Cd. Isotopic composition of snail tissues was then determined, allowing the computing of the L value, which can be considered as a biological estimate of the bioavailable Cd pool in the soil. It showed that the bioavailable pool of Cd to H. aspersa represented 58% of the total soil Cd. The Evalue, a chemical estimate of the soil Cd labile pool, was calculated with short-term isotopic exchange kinetics experiments and a time-dependent model describing the isotopic exchange over time. The E(14 days) value indicated that the labile soil Cd pool represented 49.6% of the total soil Cd. The L value was significantly higher than the E value, showing that snails accessed the nonlabile soil Cd pool, generally considered as nonbioavailable. The nonlabile pool contributed for 16% to the total Cd accumulated by snails. These results showed that the uptake of Cd in the nonlabile pool by soil organisms could be important and should be considered in risk assessment procedures for metal polluted soils. 相似文献
10.
Claire Bonhomme Sophie Beaudet-Savignat Thierry Chartier Pierre-Marie Geffroy Anne-Laure Sauvet 《Journal of the European Ceramic Society》2009,29(9):1781-1788
In the past years, a major interest has been devoted to decrease the working temperature of solid oxide fuel cells (SOFCs) down to about 700 °C.Apatite materials (La10?xSrxSi6O27?x/2) are attractive candidates for solid electrolytes, with a high ionic conductivity at 700 °C, a chemical and a dimensional stability for a pO2 ranging from 10?25 to 0.2 atm. A perovskite oxide (La0.75Sr0.25Mn0.8Co0.2O3?δ) has been used as a cathode material.Symmetrical cathode/electrolyte/cathode cells were fabricated by stacking layers obtained by tape casting of apatite and perovskite powders and co-sintering at 1400 °C for 2 h in air.Impedance spectroscopy measurements were performed on these cells in order to determine the electrode resistance. It has been shown that the latter decreases with the porosity content of the cathode and with the use of a composite material (apatite/perovskite) instead of a simple perovskite. 相似文献