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71.
Determining contributions of source-monitoring and inhibitory function to age-related forgetting has been an elusive goal for cognitive theorists. Five studies used a verbal working memory paradigm to examine mechanisms accounting for disproportionate retroactive interference (RI) experienced with adult aging. Participants distinguished studied target-word pairs from interfering pairs that were read aloud. Source-monitoring and inhibitory task components varied through manipulations of response requirements. RI effects were primarily due to source-monitoring failures rather than to inhibitory failures. Removing both source and inhibitory components eliminated age differences in RI. When source monitoring was emphasized, RI continued to be observed in all age groups but disproportionately for older adults. Process dissociation analyses of memory found recollection decreases and familiarity increases consistent with source failures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
莺歌海盆地CO2成因及运聚特征的初步研究 总被引:40,自引:2,他引:38
在已获天然气地地化资料的基础上,重点论述了CO2天然气地化特征及成因类型,追踪和判识CO2气烃类气的气源,初步了OC2气的分布特征及控制因素,指出本区CO2气属壳源型岩石化学的成因,气源主要来自莺黄组中、下部含钙海相泥岩,与深部火山慢源的CO2气无关,谱不具深源的特征。 相似文献
73.
对投电容器扰动识别和定位的方法进行了改进。针对其他此类方法的不足,比如在电压幅值低时投电容器扰动的识别、定位“可信度不高”等,文中通过提取小波变换的特定层的系数,对需要识别的电容器扰动的分解信号相对增强,而其他扰动的分解信号相对减弱,然后再提取熵特征值,结果表明它可以作为识别低电压时投电容器扰动的依据。在对电容器扰动进行定位时,参考了功率和能量定位法,并对其进行了改进。仿真分析证明,在电压幅值较低时,可以准确和可靠地对电容器扰动进行识别和定位。 相似文献
74.
Katsuhiko Fuwa Tatsuo Narikiyo Yasuyuki Funahashi 《Electrical Engineering in Japan》2002,138(4):50-60
A well‐known control system which can reduce the adverse effects of disturbances is a disturbance observer. However, in many cases of mechanical systems, system disturbances which do not satisfy the matching condition may be imposed. Therefore, it may be difficult to reduce the adverse effects of the disturbances by the traditional disturbance observer. In this paper, a method of control system synthesis for disturbance rejection using a dual observer is proposed. This method is based on the zeroing induced by the disturbance localization problem. This problem may be solved by dividing the state space into observable subspace and unobservable subspace. As compared with an H∞ controller based on perfect observation, the usefulness of the proposed control system for disturbance rejection is demonstrated by numerical simulations for a two‐mass spring system. © 2002 Scripta Technica, Electr Eng Jpn, 138(4): 50–60, 2002; DOI 10.1002/eej.1138 相似文献
75.
Acoustic Emission (AE) signals, which are electrical version of acoustic emissions, are usually analysed using a set of signal
parameters. The major objective of signal analysis is to study the characteristics of the sources of emissions. Peak amplitude(P
a
) and rise time(R
t
) are two such parameters used for source characterization. In this paper, we theoretically investigate the efficiency ofP
a
andR
t
to classify and characterize AE sources by modelling the input stress pulse and transducer. Analytical expressions obtained
forP
a
andR
t
clearly indicate their use and efficiency for source characterization. It is believed that these results may be of use to
investigators in areas like control systems and signal processing also 相似文献
76.
Criterion of Magnetic Saturation and Simulation of Nonlinear Magnetization for a Linear Multi-core Pulse Transformer 总被引:1,自引:0,他引:1
The linear multi-core pulse transformer is an important primary driving source used in pulsed power apparatus for the production of dense plasma owing to its compact,relatively low-cost and easy-to-handle characteristics.The evaluation of the magnetic saturation of the transformer cores is essential to the transformer design,because the energy transfer efficiency of the transformer will degrade significantly after magnetic saturation.This work propses analytical formulas of the criterion of magnetic saturation for the cores when the transformer driver practical loads.Furthermore,an electric circuit model based on a dependent source treatment for simulating the electric behavior of the cores related to their nonlinear magnetization is developed using the initial magnetization curve of the cores.The numerical simulation with the model is used to evaluate the validity of the criterion.Both the criterion and the model are found to be in agreement with the experimental data. 相似文献
77.
78.
79.
用真空蒸发法在玻璃和单晶硅片 (10 0 )上制备Zn薄膜 ,然后对Zn薄膜进行氧化、热处理获得纳米ZnO薄膜。对在硅片上制备的Zn薄膜一次性进行高温掺杂、氧化获得纳米ZnO∶P和ZnO∶B薄膜。研究不同氧化、掺杂温度和时间对薄膜结构、电学性能的影响。结果表明 :氧化温度和时间对ZnO薄膜结构影响较大 ,液态源掺P可明显改善纳米ZnO薄膜的导电性能、结构特性和化学组分 相似文献
80.