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61.
The authors addressed whether individual differences in the working memory capacity (WMC) of young adults influence susceptibility to false memories for nonpresented critical words in the Deese-Roediger-McDermott associative list paradigm. The results of 2 experiments indicated that individuals with greater WMC recalled fewer critical words than individuals with reduced WMC when participants were forewarned about the tendency of associative lists (e.g., bed, rest, . . .) to elicit illusory memories for critical words (e.g., sleep). In contrast, both high and low WMC participants used repeated study-test trials to reduce recall of critical words. These findings suggest that individual differences in WMC influence cognitive control and the ability to actively maintain task goals in the face of interfering information or habit. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
Miniature erbium:ytterbium fiber Fabry-Perot multiwavelength lasers   总被引:2,自引:0,他引:2  
We demonstrate stable simultaneous lasing of up to 29 wavelengths in miniature 1- and 2-mm-long Er3+:Yb3+ fiber Fabry-Perot lasers. The wavelengths are separated by 0.8 (100 GHz) and 0.4 nm (50 GHz), respectively, corresponding to the free spectral range of the laser cavity. The number of lasing wavelengths and the power stability of the individual modes are greatly enhanced by cooling the laser in liquid nitrogen (77 K). The polarization modes and linewidth of each wavelength are measured with high resolution by heterodyning with a local oscillator. The homogeneous linewidth of the Er3+:Yb 3+ fiber at 77 K is determined to be ~0.5 nm, from spectral-hole-burning measurements, which accounts for the generation of a stable multiwavelength lasing comb with wavelength separations of 0.4 nm  相似文献   
63.
In this paper, a modified particle swarm optimisation algorithm is proposed for protein sequence motif discovery. Protein sequences are represented as a chain of symbols and a protein sequence motif is a short sequence that exists in most of the protein sequence families. Protein sequence symbols are converted into numbers using a one to one amino acid translation table. The simulation uses EGF protein and C2H2 Zinc Finger protein families obtained from the PROSITE database. Simulation results show that the modified particle swarm optimisation algorithm is effective in obtaining global optimum sequence patterns, achieving 96.9 and 99.5 classification accuracy respectively in EGF and C2H2 Zinc Finger protein families. A better true positive hit result is achieved when compared to the motifs published in PROSITE database.  相似文献   
64.
In order to reliably obtain seismic responses of as-built and repaired reinforced concrete bridge columns under near-fault ground motions, pseudodynamic testing of two bridge columns with a reduced scale of 2/5 was performed. Pseudodynamic test results reveal that a ductile member may have no chance to entirely develop its ductile behavior to dissipate seismic energy, because it may suddenly be destroyed by a significant pulse-like wave. The seismic performance of the two damaged bridge columns can be recovered after repair with carbon fiber reinforced plastics composite sheets. It is also experimentally confirmed that the flexural failure moment obtained from the pseudodynamic test is in good agreement with the plastic moment predicted by the ACI 318 code. As pseudodynamic test results are believed to be more accurate than numerical solutions, they can be considered as reference solutions in developing a finite-element model. An identical specimen was tested under cyclic loading to estimate basic properties of these columns, such as shear strength, flexural strength, and ductility, so that the seismic responses obtained from pseudodynamic tests can be thoroughly discussed. Furthermore, its hysteretic response may also be used to match a mathematical model to simulate the very complicated load-displacement relation for analysis.  相似文献   
65.
This paper presents a methodology of using six-sigma quality tools for benchmarking of rapid prototyping & manufacturing (RP&M) processes. It involves the fabrication of a geometric benchmark part and a methodology to control and identify the best performance of the process to reduce the variablity in the fabricated parts. The approach is demonstrated with a case study based on the direct laser sintering (DLS) process for prototyping using plastic powder. In the case study an identified set of six-sigma/ statistical process control tools is employed to determine and best tune factors affecting the desired outcomes of the built parts.  相似文献   
66.
The purpose-built, ITER tokamak assembly tools, which are to be provided by Korea, should be designed to meet: the assembly plan, space reservations, safety standards, simple operations, efficient maintenance, and so on. It is very important that the ITER assembly tools are able to lift and transfer ITER components or their sub-assemblies to their assembled position safely. Furthermore, the lifting tools will lift and handle very heavy loads that can be more than 1200 tonnes sometimes. Therefore, the ITER lifting tools must be designed to endure these heavy load conditions with regard to their structural integrity. Also, these designs should be verified through an appropriate method. The preliminary design of the sector lifting tool and associated lifting attachments are introduced in this paper. The sector lifting tool was designed especially to lift and handle various ITER components by adjusting the lifting centre. The structural analysis results using ANSYS are described considering the heaviest load condition. The results of the analysis show that; all stresses applied on the lifting tool are lower than the allowable stress of the applied material.  相似文献   
67.
68.
Devitrified Al—transition metal—rare earth alloys offer routes to obtain higher volume fractions of dispersed strengthening phases than conventional precipitation routes. Here, we report a study of the microstructure–property relationships of an Al–Ni–Co–Y alloy processed by gas atomization and consolidated/devitrified by warm extrusion. Microstructural characterization by electron microscopy and serial section FIB tomography show that the alloy comprises an FCC Al matrix and 44 % by volume of elongated Al19(Ni,Co)5Y3 plates with the Al19Ni5Gd3 structure. The plates are aligned with the extrusion direction in the as-extruded alloy, and tensile data show a distinct anisotropy in yield strength and strain to failure. These data are consistent with the alloy acting more like a unidirectional short-fiber-reinforced metal–matrix composite than a conventional precipitation-hardened alloy. During axial upset forging, the ternary plates do not break up, but instead they rotate, until at large upset strains they lie perpendicular to their original orientation with corresponding changes in the tensile properties. The materials exhibit yield strengths of up to 713 MPa and tensile elongations of up to 5 %. Thus, such systems could form the basis for truly deformable high-strength low-density metal–matrix composites.  相似文献   
69.
70.
In Looking Backward (1888) and Equality (1897), Edward Bellamy offered two distinct but interrelated visions of a utopian future. The first and more famous book was set in a luxuriant, centralized metropolis. The sequel detailed decentralized, suburbanized infrastructures. Within the literature on Bellamy these emendations have been treated as evidence of regressive anti-urbanism. This paper argues instead that Bellamy used correlations between topography and technology to mediate an evolving approach to social reform. The discrepancies between the two texts did not represent abandonment of the city but rather an expansion of the scale and scope necessary to ensure social progress. While Looking Backward has often been invoked in relation the Garden City and City Beautiful movements, a new reading of Equality offers opportunities to rethink Bellamy’s relationship to planning history.  相似文献   
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