Speaking rate from proximal and distal contexts is used during word segmentation.

A series of eye-tracking and categorization experiments investigated the use of speaking-rate information in the segmentation of Dutch ambiguous-word sequences. Juncture phonemes with ambiguous durations (e.g., [s] in 'eens (s)peer,' “once (s)pear,” [t] in 'nooit (t)rap,' “never staircase/quick”) were perceived as longer and hence more often as word-initial when following a fast than a slow context sentence. Listeners used speaking-rate information as soon as it became available. Rate information from a context proximal to the juncture phoneme and from a more distal context was used during on-line word recognition, as reflected in listeners' eye movements. Stronger effects of distal context, however, were observed in the categorization task, which measures the off-line results of the word-recognition process. In categorization, the amount of rate context had the greatest influence on the use of rate information, but in eye tracking, the rate information's proximal location was the most important. These findings constrain accounts of how speaking rate modulates the interpretation of durational cues during word recognition by suggesting that rate estimates are used to evaluate upcoming phonetic information continuously during prelexical speech processing. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Dynamic measurements of humidity attack on polymer/ glass interfaces under stress

A simple, compact apparatus has been constructed for simultaneous tensile testing and optical microscopy in a time-resolved fashion of small adhesive droplets subjected to rapid variations in humidity. We utilize this system to study the 'attack' of humidity on the bonding of a polybutadiene rubber (PBR) and an isoprene-based pressure-sensitive adhesive (PSA) to soda lime glass. In the PBR, interfacial failure in humid air begins at a well-defined threshold stress; nevertheless, the rate of subsequent interfacial crack growth is a complex function of the sample history (stress and humidity). In PSA, interfacial failure in humid air begins soon after fibril formation (accompanying meniscus instabilities around the circumference of the adhesive drop). When humid air is introduced after fibril formation, interfacial failure begins promptly. Fibril formation produces stress concentrations which render the interface very susceptible to water attack - even at relatively low applied stresses. Although fibril formation enhances energy dissipation in PSA tested in dry air (due to fibril elongation), it limits energy dissipation in humid air (by inducing premature interfacial failure).     

On The Mechanics of Rubber-to-Metal Bond Failure

In many applications rubber is bonded to metal for fixing purposes or to alter the stiffness. Integrity of the bond is often vital to maintain the required stiffness characteristics and ensure adequate life. The mechanics of bond failure is being studied for various types of deformation. Provided tests are carried out under suitable loading conditions, time-dependent failure with a similar locus has been observed in peeling at 90° or 180°, pure shear and various combinations of simple shear and compression. There are indications that an energetics approach can enable results from different geometries to be quantitatively interrelated. Cavitation-like processes observed in the rubber in the bond region are believed to result from the constraint imposed by the metal and may be the cause of the time-dependent failure.     

Knowledge and Know‐How in Emission Control for Mobile Applications

Abstract

Concerns about emissions of carbon dioxide have created a need to develop more fuel‐efficient vehicles. Diesel engines are generally more efficient than gasoline engines but improvements in the latter can be achieved by operating under lean‐burn conditions. With both diesel and lean‐burn gasoline engines, the nitrogen oxides are emissted under oxidising conditions. It is scientifically very challenging to reduce nitrogen oxides under oxidising conditions. After a short survey of conventional three‐way catalysts, and the associated fundamental aspects of NO_x reduction under stoichoimetric conditions, this review focuses on the knowledge and know‐how that has been developed for lean engine emission control. Early research on hydrocarbon selective catalytic reduction on zeolite, oxide, and metal‐based systems is examined, and some of the key mechanistic models are described. Since none of these systems are of sufficient activity and stability to satisfy current legislation attention has turned to NO_x storage and reduction systems. The basic principles of these are described, and the present state of knowledge regarding the mechanisms of storage and regeneration are discussed. The many apparent discrepancies are highlighted and an attempt is made to rationalise the current state of knowledge by taking into account the varying experimental conditions reported nit he literature. For diesel engines, NO_x storage and reduction is not an ideal solution and so the final section of this review is concerned with silver‐based catalysts and especially with the dramatic effect of small amounts of hydrogen on the efficiency of these catalysts for hydrocarbons selective catalytic reduction.     

Stochastic effects and corona discharge for the Shroud body image generation

Answers and specifications to the comments of G. Fanti on our recent work are presented. G. Fanti invited us to revise our work, taking into account the recent discoveries on the Shroud of Turin: double superficiality of the image, corona discharge as possible source of the image formation, and continuous variation of color density of the linen fibrils. Our work was mainly devoted to investigate the macroscopic process able to explain almost all characteristics of the Shroud body image, and for such a purpose cited literature was appropriate. About the microscopic processes able to trigger the yellowing of the fibrils constituting the Shroud body image, we could also consider the corona discharge, but further investigations and deepening are necessary.     

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.     

Experimentelle und numerische Untersuchung ausgewählter zellularer Werkstoffe bei höheren Dehnraten

Experimental and numerical investigations of selected cellular solids at higher strain rates In order to research the behaviour at higher strain rates, experimental and numerical investigations on selected cellular solids were conducted. The experiments included the testing of a zinc foam and a new composite material, which is a combination of a porous mineral granulate and a matrix material. For the better understanding of phenomena observed at the real material, a model at the mesoscopic level of the material was generated using the finite element method. Effects, like the strain rate sensitivity and failure mechanisms were simulated. Furthermore, a few possible applications of the presented materials were investigated numerically.     

Temperature Dependence of Photoelectrical Properties of Single Selenium Nanowires

Influence of temperature on photoconductivity of single Se nanowires has been studied. Time response of photocurrent at both room temperature and low temperature suggests that the trap states play an important role in the photoelectrical process. Further investigations about light intensity dependence on photocurrent at different temperatures reveal that the trap states significantly affect the carrier generation and recombination. This work may be valuable for improving the device optoelectronic performances by understanding the photoelectrical properties.     

Object Kinetic Monte Carlo calculations of irradiated Fe-Cr dilute alloys: The effect of the interaction radius between substitutional Cr and self-interstitial Fe

Object Kinetic Monte Carlo models allow for the study of the evolution of the damage created by irradiation to time scales that are comparable to those achieved experimentally. Therefore, the essential Object Kinetic Monte Carlo parameters can be validated through comparison with experiments. However, this validation is not trivial since a large number of parameters is necessary, including migration energies of point defects and their clusters, binding energies of point defects in clusters, as well as the interaction radii. This is particularly cumbersome when describing an alloy, such as the Fe-Cr system, which is of interest for fusion energy applications. In this work we describe an Object Kinetic Monte Carlo model for Fe-Cr alloys in the dilute limit. The parameters used in the model come either from density functional theory calculations or from empirical interatomic potentials. This model is used to reproduce isochronal resistivity recovery experiments of electron irradiated dilute Fe-Cr alloys performed by Abe and Kuramoto. The comparison between the calculated results and the experiments reveal that an important parameter is the capture radius between substitutional Cr and self-interstitial Fe atoms. A parametric study is presented on the effect of the capture radius on the simulated recovery curves.     

Design and fabrication of novel auxetic weft-knitted fabrics with Kevlar yarns

For the purpose of fabricating three kinds of auxetic weft knitted fabrics, three different geometrical structures namely rotational structure, foldable structure and double-headed arrow topological structures with three different knit loop lengths were produced using computerized flat knitting machine. Experimental results show that all three different weft knitted fabrics have auxetic effect. The Poisson’s ratio values of the three fabrics are inversely proportional to knit loop lengths. However, differences exist between the curves of Poisson’s ratio relative to strain. With regards to the rotational and double-headed arrow topological structures, the curves tend to be monotonic, whilst that of the foldable structure takes the form of a parabola. This research thus confirms the possibility of producing auxetic fabrics based on several geometrical structures using flat knitting technology