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91.
Dark Veronica J.; Vochatzer Karl G.; VanVoorhis Bart A. 《Canadian Metallurgical Quarterly》1996,22(1):63
Semantic and spatial effects on selective processing were examined. A prime presented 250 ms or 1,000 ms before a pair of masked words was related to 1 of the words on 1/3 of the trials. Although Experiments 1 and 2 required report of both words, processing was selective; typically, just 1 word could be reported. In Experiment 1, reported words were more often top words, showing spatial selectivity, and more often words related to the prime, showing semantic selectivity. Experiment 2 included to-be-ignored peripheral cues 50 ms before the pair. Related words were reported more often at both delays, and cuing produced an additive benefit at 1,000 ms. Experiment 3 required report of just the cued word and included 100-ms cues. Cued words were reported more often, especially at 1,000 ms and with 100-ms cues, but semantic selectivity also occurred. Selectivity via semantic priming and via location reflect separate attentional mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
This study examined how indecisiveness relates to adolescents' process of choosing a study in higher education, using a longitudinal design. A sample of 281 students participated at the beginning, middle, and end of Grade 12. Findings show that indecisiveness was a risk factor for future levels of coping with the career decisional tasks of broad and in-depth environmental exploration (amount of information and exploratory behavior), amount of self-information, decisional status, and commitment. However, indecisiveness did not relate to the degree of change in decisional tasks during Grade 12. Moreover, results suggest that the linkage of indecisiveness with the amount of in-depth environmental information, the amount of self-information, decisional status, and commitment was mediated by adolescents' career choice anxiety. Finally, stability data provided support for the conceptualization of indecisiveness as a trait. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
94.
Arun Chandrasekhar Steven Brebels Serguei Stoukatch Eric Beyne Walter De Raedt Bart Nauwelaers 《Microelectronics Reliability》2003,43(3):351-357
At frequencies beyond 1 GHz, every component of the IC package contributes to the RF performance, whether required or not. In this work, we study the effects of packaging materials namely, the substrate and the globtop/underfill material on RF performance. We have measured interconnects on two area-array CSPs, the ball grid array and the polymer stud grid array using IMEC’s MCM-D technology. The measurements on the package interconnect show that the losses in the package substrate material account for about 50% of the total losses at 1.8 GHz and this drops to less than 20% at 5.2 GHz. The losses due to impedance mismatch dominate the losses especially below 10 GHz and considerable improvement in performance cannot be obtained by using an improved/expensive substrate. The other study is about the influence of globtop/underfill materials on wirebonds (through 3D EM simulations) as well as on standard 50 Ω MCM-D transmission lines (through experiments). While a higher value of dielectric constant of the globtop/underfill material is better on wirebonds, the influence of loss tangent is felt only above values of 0.1. The influence of seven different globtop/undefill materials on 50 Ω transmission lines has been used to extract their dielectric constant and loss tangent values at 30 GHz. These results are very valuable since one can hardly find the properties of globtop/underfill materials beyond 1 GHz. 相似文献
95.
The notion of pseudorandomness is the theoretical foundation on which to consider the soundness of a basic structure used in some block ciphers. We examine the pseudorandomness of the block cipher KASUMI, which will be used in the next‐generation cellular phones. First, we prove that the four‐round unbalanced MISTY‐type transformation is pseudorandom in order to illustrate the pseudorandomness of the inside round function FI of KASUMI under an adaptive distinguisher model. Second, we show that the three‐round KASUMI‐like structure is not pseudorandom but the four‐round KASUMI‐like structure is pseudorandom under a non‐adaptive distinguisher model. 相似文献
96.
Bart Pieters Charles-Frederik Hollemeersch Jan De Cock Peter Lambert Rik Van de Walle 《Signal Processing: Image Communication》2012,27(3):220-237
With the increasing number of processor cores available in modern computing architectures, task or data parallelism is required to maximally exploit the available hardware and achieve optimal processing speed. Current state-of-the-art data-parallel processing methods for decoding image and video bitstreams are limited in parallelism by dependencies introduced by the coding tools and the number of synchronization points introduced by these dependencies, only allowing task or coarse-grain data parallelism. In particular, entropy decoding and data prediction are bottleneck coding tools for parallel image and video decoding. We propose a new data-parallel processing scheme for block-based intra sample and coefficient prediction that allows fine-grain parallelism and is suitable for integration in current and future state-of-the-art image and video codecs. Our prediction scheme enables maximum concurrency, independent of slice or tile configuration, while minimizing synchronization points. This paper describes our data-parallel processing scheme for one- and two-dimensional prediction and investigates its application to block-based image and video codecs using JPEG XR and H.264/AVC Intra as a starting point. We show how our scheme enables faster decoding than the state-of-the-art wavefront method with speedup factors of up to 21.5 and 7.9 for JPEG XR and H.264/AVC Intra coding tools respectively. Using the H.264/AVC Intra coding tool, we discuss the requirements of the algorithm and the impact on decoded image quality when these requirements are not met. Finally, we discuss the impact on coding rate in order to allow for optimal parallel intra decoding. 相似文献
97.
Goutam Das Bart Lannoo Abhishek DixitDidier Colle Mario PickavetPiet Demeester 《Optical Switching and Networking》2012,9(2):156-169
For building an optical access network, we propose some new hybrid WDM/TDM passive optical network (PON) architectures that use wavelength selective switches (WSSs) at the remote node to improve flexibility, data security and power budget. Through simulations we demonstrate that the switching capabilities of a WSS can provide additional gains in terms of wavelength usage by a better statistical multiplexing. Several WSS-based hybrid WDM/TDM PON variants are proposed and assessed. These architectures are also compared with the more commonly used hybrid WDM/TDM PONs consisting of power splitters and/or arrayed wavelength gratings (AWGs), in terms of cost and power budget. 相似文献
98.
The notion of fuzzy set cardinality is examined. Zadeh's suggested measure of fuzzy cardinality, the sigma-count, is adopted and shown to generalize classical counting measure. This allows many combinatorial structures and counting techniques to be fuzzified, and hence used in knowledge representation and pattern recognition models. A fuzzy set review is found in the Appendix. 相似文献
99.
Incineration processes are critical for the environment. SO2 and NOX removal with processes is nowadays commonplace. Up to now, heavy metal were recovered via precipitation. The alternative use of liquid ion exchange techniques offers an easy re-use of the heavy metals, which are obtained as concentrates. A separation process is described, starting from laboratory experiments and ending with pilot plant field tests. A cost comparison for extraction, permeation and precipitation gives the scope of the necessary expenses for such environmentally controlled processes. 相似文献
100.
Properties of poly(butylene terephthatlate) polymerized from cyclic oligomers and its composites 总被引:1,自引:0,他引:1
The high viscosity of thermoplastic matrices hampers fiber impregnation. This problem can be overcome by using low viscous polymeric precursors such as cyclic butylene terephthalate (CBT® resins), which polymerize to form a thermoplastic matrix. This allows thermoset production techniques, like resin transfer molding (RTM), to be used for the production of textile reinforced thermoplastics. Due to the processing route and more specifically the time-temperature profile, inherent to the RTM process, the crystallites of the matrix consist out of well-defined, thick and well-oriented crystal lamellae. Together with a high overall degree of crystallinity and a low density of tie molecules, these large and perfect crystals cause polymer brittleness. Matrix brittleness lowers the transverse strength of unidirectional composites to below the matrix strength, but leaves the mechanical properties in the fiber direction unaffected. Although not a valid option for the RTM production route, crystallization from a truly random melt and at a sufficiently high cooling rate would substantially improve the ductility. 相似文献