面向新兴市场的电动助力转向系统

过去的几年中,EPS作为传统液压系统的替代产品已经进入汽车制造领域.与先前的预测相反,EPS不仅适用于小型汽车,而且某些12V中型汽车(例如大众帕萨特)也适于安装电动系统.     

Electronic Structure and Solvation Effects from Core and Valence Photoelectron Spectroscopy of Serum Albumin

X-ray photoelectron spectroscopy of bovine serum albumin (BSA) in a liquid jet is used to investigate the electronic structure of a solvated protein, yielding insight into charge transfer mechanisms in biological systems in their natural environment. No structural damage was observed in BSA following X-ray photoelectron spectroscopy in a liquid jet sample environment. Carbon and nitrogen atoms in different chemical environments were resolved in the X-ray photoelectron spectra of both solid and solvated BSA. The calculations of charge distributions demonstrate the difficulty of assigning chemical contributions in complex systems in an aqueous environment. The high-resolution X-ray core electron spectra recorded are unchanged upon solvation. A comparison of the valence bands of BSA in both phases is also presented. These bands display a higher sensitivity to solvation effects. The ionization energy of the solvated BSA is determined at 5.7 ± 0.3 eV. Experimental results are compared with theoretical calculations to distinguish the contributions of various molecular components to the electronic structure. This comparison points towards the role of water in hole delocalization in proteins.     

Effects of Heat-Affected Zone Microstructure on Fracture Toughness of Two X70 Pipe Girth Welds

In the previous study, unstable brittle crack extensions were observed during ductile tearing from all the single-edge notched bend [SE(B)] specimens with an initial crack placed in heat-affected zone (HAZ), machined from one of the two studied X70 pipe girth welds, performed at 258 K (?15 °C). Thus their microstructures and properties have been investigated using optical microscopy, microhardness measurement, and advanced scanning electron microscopy and transmission electron microscopy so as to (1) characterize their metallographic properties including crystallographic texture and (2) correlate them with the unstable brittle crack occurrence and propagation. The results suggest that HAZ softening—strength loss—is a major factor responsible for the cleavage occurrence in the given HAZ specimens as it could induce a large local strain concentration by limiting plasticity in base metal when a ductile crack crosses from the HAZ to the base metal. The HAZ softening seems to be associated with the disappearance of pearlite packets in the HAZ region, which presumably occurred during welding, for the given material. High angle grain boundaries in the fine-grained HAZ appear to affect the direction of cleavage propagation at the point of cleavage initiation (i.e., pop-in).     

Morphologie dérivationnelle et accés au lexique: Le cas des verbes préfixés et pseudo-préfixés.

Investigated the role played by morphological structure in the process of access to the lexicon. Ss completed a lexical decision test using prefixed or pseudo-prefixed verbs as well as visually introduced pseudo-verbs with radicals being verbs, nouns, or verbs and nouns. Ss were then given a test in which they selected words they saw in the 1st test from a list. Results suggest the existence of an effective morphological structure and that prefixed verbs were processed according to the nature of the radical. Verbs with radicals that could be verbs and nouns were processed faster than those for which the radical was a verb. Results obtained with pseudo-verbs showed that the prefix influenced the identification of morphologically complex items. The author concludes that these results may allow reconciliation of contradictory results in the literature by illustrating the role played by the nature of the radical. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

MBIS: Multivariate Bayesian Image Segmentation tool

We present MBIS (Multivariate Bayesian Image Segmentation tool), a clustering tool based on the mixture of multivariate normal distributions model. MBIS supports multichannel bias field correction based on a B-spline model. A second methodological novelty is the inclusion of graph-cuts optimization for the stationary anisotropic hidden Markov random field model. Along with MBIS, we release an evaluation framework that contains three different experiments on multi-site data. We first validate the accuracy of segmentation and the estimated bias field for each channel. MBIS outperforms a widely used segmentation tool in a cross-comparison evaluation. The second experiment demonstrates the robustness of results on atlas-free segmentation of two image sets from scan–rescan protocols on 21 healthy subjects. Multivariate segmentation is more replicable than the monospectral counterpart on T1-weighted images. Finally, we provide a third experiment to illustrate how MBIS can be used in a large-scale study of tissue volume change with increasing age in 584 healthy subjects. This last result is meaningful as multivariate segmentation performs robustly without the need for prior knowledge.     

Towards chip prototyping: a model for droplet formation at both T and X-junctions in dripping regime

Segmented flows in both T and X-junction glass microchannels are investigated. The effective pressure domain of use of the microchips are compared for two chemical systems. After studying the flow patterns and current empirical equations proposed in the literature, a new empirical equation is validated for both T and X-junctions allowing the prediction of not only the domain of use of the microchip in terms of flow rates knowing the viscosities of the two phases but also the droplets diameter, volume, spacing, and specific interfacial area. Specific interfacial area could be optimized using the model within our specific microsystems, and a maximum of 10,000 m^?1 is determined. Ensuing the definition of the model, several insights in the way to optimize segmented flows for different purposes are discussed, i.e., for the production of monodisperse populations of droplets and mass transfer optimization.     

Pascal's triangle: An origin of Daubechies polynomials and an analytic expression for associated filter coefficients

After showing that Daubechies polynomial coefficients can be simply obtained from Pascal's triangle by some elementary additions, we propose a derivation of the spectral factorization by using the elementary symmetric functions. This derivation leads us to present an analytic expression, able to compute Daubechies wavelet filter coefficients from the roots of the associated Daubechies polynomial. Thus, these coefficients are directly obtained and without recurrence. At last, we measure the quality of the coefficient sets generated by this expression and we compare it with two well-known methods.