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961.
Upside-down inversion disrupts the processing of spatial relations between the features of a face, while largely preserving local feature analysis. However, recent studies on face inversion failed to observe a clear dissociation between relational and featural processing. To resolve these discrepancies and clarify how inversion affects face perception, the authors monitored inversion effects separately for vertical and horizontal distances between features. Inversion dramatically declined performance in the vertical-relational condition, but it impaired featural and horizontal-relational performance only moderately. Identical observations were made whether upright and inverted trials were blocked or randomly interleaved. The largest performance decrement was found for vertical relations even when faces were rotated by 90°. Evidence that inversion dramatically disrupts the ability to extract vertical but not horizontal feature relations supports the view that inversion qualitatively changes face perception by rendering some of the processes activated by upright faces largely ineffective. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
962.
M. Losurdo M. M. Giangregorio P. Capezzuto G. Bruno R. G. Toro G. Malandrino I. L. Fragalà L. Armelao D. Barreca E. Tondello A. A. Suvorova D. Yang E. A. Irene 《Advanced functional materials》2007,17(17):3607-3612
In this study, thin films of Er2O3 are deposited by low‐pressure metal–organic chemical vapor deposition (MOCVD) using a tris(isopropylcyclopentadienyl)erbium precursor and O2 on various substrates, including p‐type Si(100), Si(111), Corning glass, and c‐axis‐oriented α‐Al2O3(0001). The resulting films are extensively characterized in order to demonstrate their applicability as antireflective and protective coatings and as high‐k gate dielectrics. The interplay existing among the substrate, the nucleation kinetics, and the resulting structural, morphological, optical, and electrical properties of Er2O3 thin films is explored. Fast nucleation governed by surface energy minimization characterizes the growth of (111)‐oriented Er2O3 on Si(100), glass, and α‐Al2O3. Conversely, nonhomogeneous nucleation leads to polycrystalline Er2O3 on Si(111) substrates. Er2O3 films grown on Si(100) possess superior characteristics. A high refractive index of 2.1 at 589.3 nm, comparable to the value for bulk single crystalline Er2O3, a high transparency in the near UV‐vis range, and an optical bandgap of 6.5 eV make Er2O3 interesting as an antireflective and protective coating. A static dielectric constant of 12–13 and a density of interface traps as low as 4.2 × 1010 cm2 eV–1 for 5–10 nm thick Er2O3 layers grown on Si(100) render the present Er2O3 films interesting also as high‐k dielectrics in complementary metal oxide semiconductor (CMOS) devices. 相似文献
963.
This contribution reviews the models for equilibrium and kinetics of the system Zn/D2EHPA/n-dodecane (and other diluents), published during the past decade, as well as values of the appropriate model parameters, i.e. of equilibrium and reaction rate constants. The reviewed kinetic models comprise those for kinetic, diffusional and mixed mass transfer regimes. It is shown that, under certain conditions, the rate equation within the kinetic regime has the same mathematical structure as the equations for the overall mass transfer rate within the diffusional and mixed mass transfer regimes. This means that the same equation interprets experimental data from each of the three regimes. Thus, a fit of experimental data to a model is not sufficient for discriminating between the mass transfer regimes. Results of kinetic experiments, using a stirred mass transfer cell with constant interfacial area, are presented. 相似文献
964.
Experiments on the organization of the combustion of kerosene in high-enthalpy supersonic air streams is analyzed. The use
of promotor additives, as well as improvements in the atomization process, vaporization, and mixing, do not always facilitate
efficient combustion development. The existence of a conversion process is found to have a significant effect on the ignition
parameters. The burnup intensity can be ensured by adding hydrogen, and the relative position of the fuel injectors is important
in that case. The fundamental role of wave structures in determining the length of the combustion zone in the channel is noted.
The integral characteristics of combustion for hydrogen and kerosene are compared.
Translated fromFizika Goreniya i Vzryva Vol. 35, No. 3, pp. 35–42, May–June 1999. 相似文献
965.
Processing procedures for the realization of fine structured channel arrays and bridging elements by LTCC-Technology 总被引:1,自引:0,他引:1
Walter Smetana Bruno Balluch Günther Stangl Sabine Seidler 《Microelectronics Reliability》2009,49(6):592-599
This report deals with technological procedures to provide channel partition walls of minimum width inside of Low Temperature Co-fired Ceramics (LTCC) micro fluidic devices demonstrated by means of the fabrication of parallel closely-spaced channels which may act as a specific functional part of a fluidic heat exchanger. Furthermore, the realization of single layer bridging elements inside of channels is discussed. Such an element may be introduced as a delicate sensor substrate providing adequate thermal insulation and low thermal mass as well. The technological processing steps under consideration start with laser micromachining of green ceramic tapes using Nd-YAG-laser equipment and are followed by a modified low-pressure lamination step comprising the application of appropriate adhesives and the incorporation of polymer sacrificial volume materials (SVMs). Consequently, the increased fraction of involved organics requires an adequate adaptation of the firing process to provide a residue-free burnout. Great attention is paid to the prevention of channel cross-section distortion and to the integrity of structures, verified by optical inspection of microsectioned samples. The optimized processing procedures enable the fabrication of channel arrays with a partition wall thickness as small as 100 μm, while single layer bridging elements may span a channel width of 4 mm. 相似文献
966.
A combinatorial auction (CA) is an auction that permits bidders to bid on bundles of goods rather than just a single item. Unfortunately, winner determination for CAs is known to be NP-hard. In this paper, we propose a distributed algorithm to compute optimal solutions to this problem. The algorithm uses nagging, a technique for parallelizing search in heterogeneous distributed computing environments. Here, we show how nagging can be used to parallelize a branch-and-bound algorithm for this problem, and provide empirical results supporting both the performance advantage of nagging over more traditional partitioning methods as well as the superior scalability of nagging to larger numbers of processors. 相似文献
967.
Gwen Amice Bruno Giguere 《通讯世界》2009,(4):76-77
如果您的网络工程团队已决定实施可重新配置的光分插多路复用器(ROADM)基础设施,那么现在需要做些什么?在项目从技术调查到现场试验再到最终部署的过程中,哪些问题会不期而遇?您正在创建将多个环折叠在一起的网络拓扑,这种基础设施将在多大程度上影响您的故障诊断能力? 相似文献
968.
Macroporous or mesoporous hydrophobic inorganic membranes are prepared by a simple one-pot synthesis method coupling the sol–gel
process with fluorinated silanes as precursors and the use of alumina powders as fillers. The porosity of these intrinsically
hydrophobic membranes can be tuned by the particle size distribution of the dispersed alumina powder. These membranes developed
for water/gas separation applications are characterized in term of gas permeance and water breakthrough pressure. A value
of air permeance equal to 1800 L min−1 bar−1 m−2 associated with a water breakthrough pressure larger than 10 bar are measured for the effective sample. 相似文献
969.
The contributions of striatal D1 receptors to the expression of sensorimotor behavior are qualitatively different in rats depleted of dopamine (DA) as neonates vs. as adults. In an effort to reveal neuronal mechanisms underlying these behavioral difference we determined the effects of the partial D1 agonist SKF 38393, the muscarinic antagonist scopolamine, and the combination of the two drugs on the induction of c-fos in the striatum and its projection sites, the globus pallidus and substantia nigra. Adult rats, given intracerebroventricular injections of 6-hydroxydopamine (6-OHDA, 50 micrograms/5 microliters/hemisphere) or its vehicle on postnatal day 3, were treated with SKF 38393 (1.5 mg/kg, i.p.), scopolamine (5.0 mg/kg, i.p.) or the combination of the two drugs. There was no significant induction of c-fos in vehicle-treated controls, regardless of drug administration. In DA-depleted rats, scopolamine also did not induce c-fos whereas SKF 38393 produced a significant increases in the number of FOS-positive cells in the dorsal, but not ventral, striatum. The combined administration of scopolamine and SKF 38393 resulted in a potent synergism in the number of FOS-positive cells in DA-depleted rats. These interactions between lesion condition and drugs on c-fos induction were not secondary to differences in drug-induced behavioral activity. Activity levels were no different in vehicle vs. DA-depleted rats following the combined administration of scopolamine + SKF 38393, yet the two groups of rats exhibited marked differences in the density of FOS-positive striatal neurons. The effects of scopolamine and SKF 38393 on c-fos induction in striatum are qualitatively similar to those reported in rats DA-depleted as adults and suggest that, at this single-label level of analysis, the ability of D1 and muscarinic receptors to influence striatal activity does not contribute to the marked age-related differences in the behavioral effects of DA depletions. 相似文献
970.