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991.
Investigated the effects of age and passage of time on incidental and prospective/intentional everyday memory. 79 23–93 yr old volunteers were tested twice, and 33 of the Ss were tested 3 times over an 18-mo period. They were asked to recognize or recall, either in writing or orally, experiences from a 3-day period in which they served as research Ss. Results demonstrate that incidental, but not prospective/intentional, memory appeared to be influenced by age and passage of time. Results imply that salience and context are important factors in aging memory performance and that certain types of everyday retrospective reports may be reliable. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Jan Blochwitz-Nimoth 《电子与电脑》2005,(1):116-117
虽然最近几年有机发光二极管(Organic LjghtEmission Diode,OLED)显示器已经商品化,不过OLED显示器不论是发光效率、使用寿命,或是改用无晶硅基大型面板等问题仍有待改善. 相似文献
993.
Mao-Sung Wu Pin-Chi Julia Chiang Jung-Cheng Lin Yih-Song Jan 《Electrochimica acta》2004,49(11):1803-1812
The shutdown function of a separator is an important factor in the safety of advanced lithium-ion batteries (ALB). When a separator without proper shutdown function is used, battery safety would depend on the thermal stability of electrode materials. Results show that thermal stability of a battery, contributed from both the anode and cathode, decreases noticeably after cycling. DSC shows that exothermicity from SEI decomposition and the reaction of the lithiated graphite and electrolyte around 140 °C increases as cycle number increase; main reason is the gradual thickening of passivation film, observed through three-electrode ac impedance measurements. DSC also shows a similar trend of exothermicity for LixCoO2 cathode. The lesser the amount of lithium (x-value) in LixCoO2, the larger the exothermicity and the lower the decomposition temperature. Using a three-electrode system to observe the changes of open-circuit potential in LixCoO2 cathode, thermal instability is a consequence of decreased lithium content as cycle increases. 相似文献
994.
995.
The subject of this three-part paper is the multidimensional nonlinear Schur parametrization problem for higher-order (and non-Gaussian) stochastic signals. In the first part of this paper we state the nonlinear orthogonal parametrization problem as a generalization of the linear prediction/innovations filter problem. A unified geometric approach to the problem is introduced in the following three isometrically isomorphic spaces: of random variables (of higher-order stochastic sequences), of multi-indexed matrices, and of multidimensional z-polynomials. The nonlinear orthogonal approximate filters of the Volterra–Wiener class are considered. In the second part [30] of this paper we derive a generalized multidimensional nonlinear Schur parametrization algorithm for higher-order nonstationary stochastic sequences. The third part [33] of the paper is devoted to the complexity reduction problem in the nonlinear case, where a low-complexity Schur parametrization procedure, following from a nonlinear generalization of the staircase matrix extension problem [13], is proposed. 相似文献
996.
Study of the water uptake of polyamide 46 based copolymers by magnetic resonance imaging relaxometry
Magnetic resonance imaging (MRI), NMR relaxometry, thermal analysis and gravimetrical experiments are performed to study the water absorption by neat PA46 and copolymers of PA46 and PA4n (PA46-co-PA4n) with 4 mol% n=8, 12 and 16. The observed reduction in water uptake, ingress rate and water molecular mobility with increasing value of n is explained by a combination of several physico-chemical molecular properties. The increased [CH2]/[amide] ratio and the reduced amount of crystallinity do not completely clarify the observed trends in water uptake and water molecular mobility in the copolymer series. It is shown that the increased chain mobility of the PA46 segments in the copolymers allows an improved coupling of the amide groups in the amorphous phase, explaining the observed decrease in water uptake. The important role of the morphology of the amorphous phase for water uptake is further demonstrated by annealing results and NMR relaxation experiments as a function of temperature. 相似文献
997.
A. Špalek O. Dragoun M. Ryšavý V. Brabec A. Kovalík A. F. Novgorodov 《Measurement Techniques》1997,40(8):803-806
Experimental spectra of the169Yb conversion lines having kinetic energies of 3.7–18.4 keV and the beta spectrum from the decay of241Pu are compared with calculations by the Monte Carlo method which take into account the individual elastic and inelastic scattering
processes of the electrons in the source, in the substrate, and in a carbon layer contaminating the source. Good agreement
is obtained between the theoretical and experimental results. It is also shown that the scattering of the electrons depends
on their emission angle.
Translated from Izmeritel'naya Tekhnika, No. 8, pp. 63–65, August. 1997. 相似文献
998.
Bert Blocken Jan Carmeliet 《Journal of Wind Engineering & Industrial Aerodynamics》2005,93(12):905-928
With the specific intention to provide experimental data for model development and model validation, a new measurement setup for wind, rain and wind-driven rain (WDR) has been designed and installed at the Laboratory of Building Physics (Katholieke Universiteit Leuven). This paper focuses on the new measurement setup and on the obtained measurement results. The CFD-based design and the installation of the measurement setup are outlined and samples of the database containing the wind, rain and high-resolution WDR measurements are provided and discussed. This paper also provides the link to a website from which the experimental WDR database can be downloaded. Finally, the use of these data to determine WDR coefficients and their use in WDR assessment are briefly addressed. 相似文献
999.
Development of software product families relies heavily on the use of variability to manage the differences between products by delaying design decisions to later stages of the development and usage of the constructed software systems. Implementation of variability is not a trivial task, and is governed by a number of factors. In this paper, we describe the factors that are relevant in determining how to implement variability, and present a taxonomy of variability realization techniques. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
1000.
Karun Mehta Jan Fong Jue Anil V. Virkar 《Journal of the American Ceramic Society》1990,73(6):1777-1779
Ceria- and yttria-doped tetragonal polycrystalline zirconia ceramics were ground at temperatures as high as 1100°C. X-ray diffraction revealed that the intensity ratio I (002) / I (200) increased (to as high as ∼4.5) compared with that from the as-sintered surfaces (∼0.55). The enhancement in I (002) / I (200) at temperatures well above the m → t transition temperature shows that it is not related to transformation, reversible or otherwise, but can be explained by ferroelastic domain switching. 相似文献