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41.
Relation algebras from cylindric and polyadic algebras 总被引:1,自引:0,他引:1
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本文对1—5岁汉族儿童使用双宾结构的状况进行了考察。首先对儿童语言中双宾结构的结构类型、句法功能及其发展状况进行了描述分析;在此基础上,讨论了儿童习得汉语双宾结构的机制。 相似文献
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MEMORY PROCESSES IN DELAYED SPATIAL DISCRIMINATIONS: RESPONSE INTENTIONS OR RESPONSE MEDIATION? 总被引:2,自引:2,他引:0 下载免费PDF全文
Pigeons were trained on a pair-comparison task in which left versus right choices were reinforced following different sequences of two center-key stimuli. Choice accuracy was higher when retention intervals occurred after the entire sequence than when they separated the two stimuli comprising it, and this effect occurred independently of whether the initial and terminal stimuli came from the same or different dimensions. The initial stimulus from the prior trial was a source of proactive interference only in groups for which the retention interval separated the two sequence stimuli. By contrast, differential delay-interval behavior was observed only in groups for which the retention interval followed presentation of the entire sequence. These results indicate that coding processes in delayed discriminations are influenced by the location of the retention interval, and that response mediation affects retention performances if the reinforced choice can be determined prior to the interval. 相似文献
45.
The standard Pawlak approach to rough set theory, as an approximation space consisting of a universe U and an equivalence (indiscernibility) relation R
U x U, can be equivalently described by the induced preclusivity ("discernibility") relation U x U \ R, which is irreflexive and symmetric.We generalize the notion of approximation space as a pair consisting of a universe U and a discernibility or preclusivity (irreflexive and symmetric) relation, not necessarily induced from an equivalence relation. In this case the "elementary" sets are not mutually disjoint, but all the theory of generalized rough sets can be developed in analogy with the standard Pawlak approach. On the power set of the universe, the algebraic structure of the quasi fuzzy-intuitionistic "classical" (BZ) lattice is introduced and the sets of all "closed" and of all "open" definable sets with the associated complete (in general nondistributive) ortholattice structures are singled out.The rough approximation of any fixed subset of the universe is the pair consisting of the best "open" approximation from the bottom and the best "closed" approximation from the top. The properties of this generalized rough approximation mapping are studied in the context of quasi-BZ lattice structures of "closed-open" ordered pairs (the "algebraic logic" of generalized rough set theory), comparing the results with the standard Pawlak approach. A particular weak form of rough representation is also studied. 相似文献
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Gran Carlsson 《Scandinavian journal of psychology》1997,38(4):265-273
A list-learning paradigm was used to study learning and memory of verbal and figurative material in children with right versus left-sided hemiplegic cerebral palsy. Thirty-one children with right (n=18), or left (n=13) congenital hemiplegia were compared with normal controls (n=19). All children had normal intelligence (IQ>80), and were attending standard schools. The inclusion criteria for the two hemiplegic groups were; no epilepsy, no hearing or visual impairments, and a mild to moderate hemiparesis. The aim of this study was to explore material-specific (words and drawings) differences in the acquisition, recall and serial position effects in children with an early unilateral brain lesion. The left-hemisphere impaired (i.e. right hemiplegia) group showed impaired acquisition for drawings, as compared with the normal controls. There was also a material-specific difference in the serial position effect for all three groups. Learning of words followed the primacy principle, whereas the learning of drawings followed the recency principle. There were no group-differences in delayed-recall (i.e. long-term memory) for either words or drawings. The results are discussed in terms of acquisition and retention of verbal and figurative materials in relation to lesion side and size. 相似文献
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This study examined how preschool inattention-hyperactivity is related to elementary school reading achievement. Prereading skills were hypothesized to be a link between them. This link was explored using longitudinal data on 105 low-socioeconomic-status (SES) children's inattentive-hyperactive behavior and prereading skills in Head Start and in kindergarten and their inattentive-hyperactive behavior and reading skills in first grade. A model of this relationship was tested using structural equation modeling. The results failed to show a significant path between inattention-hyperactivity and prereading skills at both the Head Start and kindergarten levels. A significant path was found between first grade inattention-hyperactivity and reading skills, confirming that the strong relationship between inattention-hyperactivity and poor reading achievement commonly found in children from other SES levels was also significant in this low-SES sample. Strong relationships were found between pre-reading skills and reading skills, as well as among hyperactivity levels at the three grades. The issue of the direction of the path of influence between attention-behavior and reading achievement is addressed briefly; however, the results indicate that further longitudinal work is necessary to resolve this issue. 相似文献
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We studied the academic effects on peers without disabilities of serving as peer supports for students with disabilities in general education classrooms. Three peers were studied using a range of indicators, including academic engagement, coursework performance, and social validity assessments. Peers assisting a student with disabilities via curricular adaptation, assignment completion, and social facilitation constituted the multicomponent independent variable. We used withdrawal or multiple baseline designs to demonstrate positive benefits for peers for all measures used. In addition, follow-up data for 2 peers indicated that the positive changes associated with serving as a peer support were maintained for up to 2 months. Our results are discussed in relation to the possible academic and social effects of providing peer supports in general education classrooms for students with and without disabilities. 相似文献
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Three students with moderate disabilities were taught to read and match-to-sample sight words comprising stimulus sets based upon the four food groups. We taught students conditional discriminations within four four-member sets using a single-sample/four-comparison procedure. Students were taught A-B, B-C, and C-D conditional discriminations for each of the four potential stimulus classes. Subsequent probes tested for relations based upon symmetry and one-node and two-node transitivity. The performances for all students indicated that symmetric relations emerged before one-node transitive relations, and that one-node transitive relations emerged before two-node transitive relations. These results are consistent with a pattern of responding, referred to as a "nodality effect," in which relations with fewer nodes are demonstrated prior to the demonstration of relations with a greater number of nodes. These results extend this area of research to sight-word reading for students with moderate disabilities. 相似文献
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