Word-identification priming for ignored and attended words

Three experiments examined contributions of study phase awareness of word identity to subsequent word-identification priming by manipulating visual attention to words at study. In Experiment 1, word-identification priming was reduced for ignored relative to attended words, even though ignored words were identified sufficiently to produce negative priming in the study phase. Word-identification priming was also reduced after color naming relative to emotional valence rating (Experiment 2) or word reading (Experiment 3), even though an effect of emotional valence upon color naming (Experiment 2) indicated that words were identified at study. Thus, word-identification priming was reduced even when word identification occurred at study. Word-identification priming may depend on awareness of word identity at the time of study.     

Online pricing for bandwidth provisioning in multi-class networks

We consider the problem of pricing for bandwidth provisioning over a single link, where users arrive according to a known stochastic traffic model. The network administrator controls the resource allocation by setting a price at every epoch, and each user’s response to the price is governed by a demand function. We formulate this problem as a partially observable Markov decision process (POMDP), and explore two novel pricing schemes––reactive pricing and spot pricing––and compare their performance to appropriately tuned flat pricing. We use a gradient-ascent approach in all the three pricing schemes. We provide methods for computing unbiased estimates of the gradient in an online (incremental) fashion. Our simulation results show that our novel schemes take advantage of the known underlying traffic model and significantly outperform the model-free pricing scheme of flat pricing.     

Finite element study of the fibre–matrix interface behaviour of [10°/90°] laminated composites under tensile loading

A three-dimensional unit cell has been developed and modelled using the finite element method to investigate the interface failure behaviour of SiCf/Si3N4 composites under tensile loading at room and elevated temperatures. The model idealizes the composite as a regular rectangular array of fibres in 0° and 90° orientations embedded in the matrix. It introduces three-dimensional contact elements between the fibre and the matrix to simulate the interface conditions between the two phases. Slippage between 0° and 90° layers is also considered by introducing another set of contact elements at the layer separation planes. Two interface conditions, namely, infinitely strong and weakly bonded, are considered to establish the correlation with the experimental data. To simulate the weak interface, the fibre and the matrix are assumed to slide over one another with shear stress through the Coulomb mechanism. The same assumption has been adopted for the layer separation planes. A finite element model utilizing these concepts has been developed. Stress–strain behaviour and the local stress distributions at various ambient temperatures within the unit cell, are presented. The investigation has also been extended to include the effects of residual stresses in the finite element model. It is shown that the model yields results that correlated reasonably well with the experimental data. © 1998 Kluwer Academic Publishers     

Anisotropic behaviour of semiconducting tin monosulphoselenide single crystals

Single crystals of ternary mixed compounds of group IV-VI in the form of a series, SnS_xSe_1-x (wherex = 0, 0.25, 0.50, 0.75 and 1), have been grown using direct vapour transport technique. The grown crystals were characterized by the X-ray diffraction analysis for their structural parameter determination. All the grown crystals were found to be orthorhombic. The microstructure analysis of the grown crystals reveals their layered type growth mechanism. From the Hall effect measurements Hall mobility, Hall coefficient and carrier concentration were calculated with all crystals showingp-type nature. The d.c. electrical resistivity measurements perpendicular toc-axis (i.e. along the basal plane) in the temperature range 303–453 K were carried out for grown crystals using four-probe method. The d.c. electrical resistivity measurements parallel to c-axis (i.e. perpendicular to basal plane) in the temperature range 303–453 K were carried out for the same crystals. The electrical resistivity measurements showed an anisotropic behaviour of electrical resistivity for the grown crystals. The anisotropic behaviour and the effect of change in stoichiometric proportion of S and Se content on the electrical properties of single crystals of the series, SnS_xSe_1-x (wherex = 0, 0.25, 0.50, 0.75 and 1), is presented systematically.     

Numerical and Experimental Studies of Substrate Melting and Resolidification during Thermal Spraying

A good understanding of melting and resolidification of the substrate will help us to achieve better bonding. Anumerical model is developed to investigate the solidification of the droplet, and melting and resolidification of thesubstrate. The molybdenum     

Text processing system

An economical microprocessor-based text processing system utilizing recently available low cost digital data recorders is described. Ordinary audiocassettes are used to store both text and data and as such the technique should appeal to computer hobbyists as well as manufacturers of VDUs and word processing equipment.     

Stacking faults in sic particles and their effect on the fracture behavior of a 15 Vol Pct SiC/6061-AI matrix composite

Mechanical tests and microstructural examinations performed on a SiC-particle-reinforced 6061-A1 matrix composite indicate that particle cracking during mechanical testing significantly affects the failure mechanisms of the composite. Microcracks were observed to nucleate and propagate on stacking faults and interfaces between the 4H (or 3C) and 6H hexagonal phases within the SiC particle reinforcements. These planar defects were the predominant defects seen in the SiC particles. Partial dislocations, having a 1/3 (10άrc10) Burgers vector, were also observed bounding the stacking faults in the reinforcement phase.     

Self-organizing map network as an interactive clustering tool — An application to group technology

The Self-Organizing Map (SOM) network, a variation of neural computing networks, is a categorization network developed by Kohonen. The theory of the SOM network is motivated by the observation of the operation of the brain. This paper presents the technique of SOM and shows how it may be applied as a clustering tool to group technology. A computer program for implementing the SOM neural networks is developed and the results are compared with other clustering approaches used in group technology. The study demonstrates the potential of using the Self-Organizing Map as the clustering tool for part family formation in group technology.