Parametric animation of performance‐captured mesh sequences

In this paper, we introduce an approach to high‐level parameterisation of captured mesh sequences of actor performance for real‐time interactive animation control. High‐level parametric control is achieved by non‐linear blending between multiple mesh sequences exhibiting variation in a particular movement. For example, walking speed is parameterised by blending fast and slow walk sequences. A hybrid non‐linear mesh sequence blending approach is introduced to approximate the natural deformation of non‐linear interpolation techniques whilst maintaining the real‐time performance of linear mesh blending. Quantitative results show that the hybrid approach gives an accurate real‐time approximation of offline non‐linear deformation. An evaluation of the approach shows good performance not only for entire meshes but also with specific mesh areas. Results are presented for single and multi‐dimensional parametric control of walking (speed/direction), jumping (height/distance) and reaching (height) from captured mesh sequences. This approach allows continuous real‐time control of high‐level parameters such as speed and direction whilst maintaining the natural surface dynamics of captured movement. Copyright © 2012 John Wiley & Sons, Ltd.     

Spatial correlation in grain misorientation distribution

Grain misorientation was studied in relation to the nearest neighbor’s mutual distance using electron back-scattered diffraction measurements. The misorientation correlation function was defined as the probability density for the occurrence of a certain misorientation between pairs of grains separated by a certain distance. Scale-invariant spatial correlation between neighbor grains was manifested by a power law dependence of the preferred misorientation vs. inter-granular distance in various materials after diverse strain paths. The obtained negative scaling exponents were in the range of ?2 ± 0.3 for high-angle grain boundaries. The exponent decreased in the presence of low-angle grain boundaries or dynamic recrystallization, indicating faster decay of correlations. The correlations vanished in annealed materials. The results were interpreted in terms of lattice incompatibility and continuity conditions at the interface between neighboring grains. Grain-size effects on texture development, as well as the implications of such spatial correlations on texture modeling, were discussed.     

Categorization processes in mental comparisons.

Five experiments explore categorization and category-based congruity effects in mental comparisons. The first 4 experiments concentrate on categorization of infinite-set small items. The experiments vary the additional items presented and whether those items appear once (Experiments 1-2) or repeatedly (Experiments 3-4). Additional items include other small items (Experiment 1), relatively large items (Experiments 2-4), and items involving nonsize dimensions (Experiment 4). The critical small items show a complete congruity effect only in Experiments 1 and 3. Results suggest that categorization of infinite-set items may be based on range information alone (Experiment 1) but that multiple categorizations based on multiple ranges (Experiment 2) may require attentional effort. Results implicate categorization as a central process in mental comparison, despite differences in ease of categorization across paradigm. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of the microstructure of aluminium alloys on their residual impact properties after a fatigue loading program

Consecutive loadings of fatigue and impact have been carried out on aluminium alloys. The aim of this study is to quantify the influence of the microstructure on the residual impact behavior after a prior fatigue loading. Two alloys with different chemical compositions and hardening modes have been investigated: 2017A-T3 used in the aircraft industry and 5454-O used in automotive applications.The fatigue pre-loadings were carried out under fully reversed tensile-compression with several pairs (stress level, number of cycles) in the high cycle fatigue zone (10⁵– 10⁶cycles). The residual impact behavior was determined under tensile loading, in the range of medium strain rates (about ). To assess the prior fatigue damage and to follow its evolution during the impact loading, observation of the specimens (surface and fracture surfaces) were made.From this study, two conclusions have been highlighted: (1) there is no direct correlation between a given prior loading and residual behavior, whatever the material; (2) the material aspect is fundamental. At the mechanical (macroscopic) scale, the Al–Mg alloy (5454-O) remains insensitive to the prior fatigue loading whereas the Al–Cu alloy (2017A-T3) undergoes a large modification in its residual performance. At a lower scale, the pre-damage signature appears for the insensitive as well as for the sensitive material. The prior damage and its contribution to the process fracture appear to be strongly linked with the material’s microstructure.     

Efficient Enantioselective Hydrosilylation of Aryl Ketones Catalyzed by a Chiral BINAP‐Copper(I) Catalyst‐Phenyl(methyl)silane System

The Cu(I)‐chiral diphosphine (BINAP) system was found to efficiently catalyze the hydrosilylation of aryl alkyl ketones with excellent enantioselectivities by using phenyl(methyl)silane as stoichiometric hydride source.     

Transesterification of rapeseed oil in the presence of basic zeolites and related solid catalysts

The transesterification of rapeseed oil with methanol was performed by reflux of methanol over cesium-exchanged NaX faujasites, mixed magnesium-aluminum oxides, magnesium oxide, and barium hydroxide for different methanol-to-oil ratios. Over cesium-exchanged NaX faujasites and mixed magnesium-aluminum oxides, a long reaction time and a high methanol-to-oil ratio are required to achieve both high oil conversion and high yields in methyl esters. However, over a 300 m²/g magnesium oxide, methanol-to-oil ratios and reaction times are significantly reduced to obtain both high oil conversion and high yield in the methyl esters, particularly when the hydroxide precursor is calcined at 823 K. Finally, preliminary results with other basic solids such as barium hydroxide have shown a very high activity and a very high yield in esters. This catalyst is particularly effective since, for a methanol-to-oil ratio of 6, at reflux of methanol and after a reaction time of only 1 h, the oil conversion is about 80% with a nearly quantitative ester molar fraction. Part of this work was presented at the 91st AOCS Annual Meeting, San Diego, California, April 2000.