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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.
The authors examined whether participants can shift their criterion for recognition decisions in response to the probability that an item was previously studied. Participants in 3 experiments were given recognition tests in which the probability that an item was studied was correlated with its location during the test. Results from all 3 experiments indicated that participants' response criteria were sensitive to the probability that an item was previously studied and that shifts in criterion were robust. In addition, awareness of the bases for criterion shifts and feedback on performance were key factors contributing to the observed shifts in decision criteria. These data suggest that decision processes can operate in a dynamic fashion, shifting from item to item. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
73.
周景洲 《电子学报》2002,30(Z1):2146-2148
应用相关的存储技术实现模式识别可缩减存储大小,但由此带来的饱和问题严重影响系统正常工作,为解决此问题,本文在分析现有系统的基础上给出了基于一系列逻辑操作的识别技术.该技术的实质是用一形式化的方法增加输入模式间的线性无关性.通过论证与实例验证,该方法是有效而实用的.  相似文献   
74.
Banaji and Crowder (see record 1990-00387-001) contend "that the movement to develop an ecologically valid psychology of memory has proven itself largely bankrupt" (p. 1185). The authors have two primary concerns. First, they believe that it is rare for studies of real-world cognition to support conclusions that generalize broadly. Second, they are concerned that such studies may be inherently incapable of making significant theoretical or methodological contributions. The research program outlined here can be viewed as a response (in the form of a case study) to the Banaji and Crowder position. Specifically, this project has adopted both theoretical and methodology perspectives from the study of real-world memory to address a long-standing issue in the mainstream memory literature. The project itself was designed to characterize the strategies used to estimate event frequency and the conditions that foster the use of these strategies. A valid model of the estimation process is necessary in order to understand the encoding and representation of event frequency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
提出一种改进4管自体偏压结构SRAM/SOI单元.基于TSUPREM4和MEDICI软件的模拟和结构性能的分析,设计单元结构并选取结构参数.该结构采用nMOS栅下的含p+埋沟的衬底体电阻代替传统6管CMOSSRAM单元中的pMOS元件,具有面积小、工艺简单的优点.该结构可以在0.5V的电源电压下正常工作,与6管单元相比,该单元瞬态响应正常,功耗只有6管单元的1/10,满足低压低功耗的要求.  相似文献   
76.
内嵌闪存MCU的高性能多通道24位采集系统ADuC845   总被引:6,自引:0,他引:6  
ADuC845是ADI公司新推出的嵌有单指令周期8052闪存MCU、带两路24位∑ -△A/D、双12位D/A以及两个灵活脉宽调制输出的高性能24位数据采集与处理系统芯片。该芯片的数据处理速度达12MIPS,且设计简单 ,噪声低 ,非常适用于精密仪器仪表。文中详细介绍了该芯片的功能特点和工作原理 ,给出了该芯片的应用方法。  相似文献   
77.
The present investigation showed that the re-laxation peak at about 200℃ (f≈1Hz) was relatedto bainitic transformation in a CuZnAl alloy.Thepeak decreased when bainite precipitated.Theactivation energy of the peak was the same as theapparent activation energy of bainitic transforma-tion.According to the relations between the peakand the bainitic transformation,the mechanism ofthe peak has been discussed.  相似文献   
78.
在Banach空间中并在不具紧性的条件下,引入和研究了一类fuzzy多值隐拟变分包含及相应的fuzzy隐预解算子方程,借助预解算子技巧,建立了Banach空间中fuzzy多值隐拟变分包含与预解算子方程的等价性,得到了该类fuzzy多值隐拟变分包含的迭代算法与某些解的存在性定理及解的迭代逼近。  相似文献   
79.
In this paper, we consider a method (splitting) for calculating the auto- covariances of fractional integrated processes (ARFIMA) and generalized integrated processes (GARMA). The splitting method does not require any restriction on the autoregressive roots, and allows fast calculation of the autocovariances of these processes.  相似文献   
80.
The structure of working memory and its development across the childhood years were investigated in children 4-15 years of age. The children were given multiple assessments of each component of the A. D. Baddeley and G. Hitch (1974) working memory model. Broadly similar linear functions characterized performance on all measures as a function of age. From 6 years onward, a model consisting of 3 distinct but correlated factors corresponding to the working memory model provided a good fit to the data. The results indicate that the basic modular structure of working memory is present from 6 years of age and possibly earlier, with each component undergoing sizable expansion in functional capacity throughout the early and middle school years to adolescence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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