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21.
Four experiments provide evidence that people are biased to associate particular types of motion with nouns and different types of motion with verbs. Novel nouns and verbs were related to two types of motion: (1) path, or the direction of motion of one character with respect to the other character, and (2) movement orientation, or the direction a character was facing as it moved. Subjects associated verbs more strongly with path than with movement orientation. In contrast, they associated nouns more strongly with movement orientation than with path. Movement orientation was associated with both object categories and verbs, inconsistent with a complete division of labor between these two types of categories. These results are consistent, however, with the notion that people are biased to associate verbs with relations between objects, whereas they are biased to associate object categories with motions defined with respect to the object carrying out those motions.  相似文献   
22.
This research investigated the learning of event categories, in particular, categories of simple animated events, each involving a causal interaction between 2 characters. Four experiments examined whether correlations among attributes of events are easier to learn when they form part of a rich correlational structure than when they are independent of other correlations. Event attributes (e.g., state change, path of motion) were chosen to reflect distinctions made by verbs. Participants were presented with an unsupervised learning task and were then tested on whether the organization of correlations affected learning. Correlations forming part of a system of correlations were found to be better learned than isolated correlations. This finding of facilitation from correlational structure is explained in terms of a model that generates internal feedback to adjust the salience of attributes. These experiments also provide evidence regarding the role of object information in events, suggesting that this role is mediated by object category representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
Five clustering techniques are compared by classifying a polarimetric synthetic aperture radar image. The pixels are complex covariance matrices, which are known to have the complex Wishart distribution. Two techniques are fuzzy clustering algorithms based on the standard /spl lscr//sub 1/ and /spl lscr//sub 2/ metrics. Two others are new, combining a robust fuzzy C-means clustering technique with a distance measure based on the Wishart distribution. The fifth clustering technique is an application of the expectation-maximization algorithm assuming the data are Wishart. The clustering algorithms that are based on the Wishart are demonstrably more effective than the clustering algorithms that appeal only to the /spl lscr//sub p/ norms. The results support the conclusion that the pixel model is more important than the clustering mechanism.  相似文献   
24.
A primary prevention, behavioral intervention designed to reduce HIV risk behavior was tested in a randomized, controlled trial with single, inner-city women. A total of 935 women were randomly assigned to 1 of 3 conditions: a small group, 6-session communally oriented HIV prevention intervention; a yoked general health promotion intervention control; or a standard care control. Both interventions involved the interactive use of videotapes by live group leaders. The HIV prevention intervention, in particular, resulted in significant positive effects on self-reported and behaviorally assessed safer-sex behavior. Women in the HIV prevention group showed reduced point prevalences of medically tested sexually transmitted diseases at follow-up in some comparisons. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
25.
Zusammenfassung An Hand verschiedener Ausführungsbeispiele aus neuerer Zeit wird die Brauchbarkeit des freitragenden Holzbaues für Aufgaben des Hoch- und Ingenieurbaues unter Beweis gestellt. Besonderer Dank sei den Stellen gesagt, die dem Verf. entgegenkommenderweise von ihm erbetene Unterlagen zur Verfügung stellten.  相似文献   
26.
The LEMMA is a proposed conceptual design of a remote teleoperator manipulator arm with 6 degrees of freedom, exclusive of the end-effector. The bevel gear arrangement in 4 of the 6 degrees of freedom, together with the concentric-tubular arm configuration, requires a unique and a novel drive mechanism. This differential drive assembly, housed in the shoulder, is a self-compensating device and simplifies the matrix solution for the resolved motion rate control system needed to guide the arm in its performances. The article will describe the need for the 6 degrees of freedom as established by the work envelope, the functioning of the differential shoulder drive, the arm and joint configuration, and the anticipated degree of accuracy.  相似文献   
27.
Despite the enormous potential repertoire of gammadelta T cells, there are several observations which suggest that the expressed gammadelta repertoire in the periphery of normal individuals is often quite restricted. To assess selective expansions among gammadelta T cells from both adult and newborn blood samples, PBMC from 12 normal adults and cord blood from 15 normal newborns were analyzed for TCRDV1 and TCRDV2 junctional diversity by CDR3 size spectratyping and single-strand conformational polymorphism. Although TCRBV usage showed extensive heterogeneity in adults and newborns, both populations often showed CDR3 region restriction for TCRDV1 and TCRDV2. Analysis of the CDR3 spectratype patterns of newborn twins suggested that clonal selection for TCRDV is independent of genetic background. The possible role of Gram-negative bacteria in driving selective responsiveness of gammadelta T cells in PBMCs from adults was examined by in vitro stimulation with Escherichia coli and Pseudomonas aeruginosa. Donors whose TCRDV repertoire was highly clonal in the unstimulated blood cells showed the same predominant clones among the bacteria-stimulated cultures. In individuals whose gammadelta T cells were less restricted, in vitro stimulation did not select for clonality; rather, the TCRDV repertoires were similar before and after bacterial stimulation. Together, these data indicate that gammadelta T cells are often clonally restricted in adults as well as in newborns and suggest that the prominent stimulatory activity of Gram-negative bacteria does not by itself account for the restriction or diversity of the gammadelta T cell repertoire.  相似文献   
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29.
Use of a simplified method has been made to calculate the time-dependent thermal performance of various solar domestic hot water systems. to establish the value of solar hot water systems under given economic considerations a thermal analysis was carried out on three basic energy system designs, operating at several locations in the Federal Republic of Germany (F.R.G.) with various solar collectors. It is found that systems design can result in variations up to a factor of two in the per cent solar output. the location and year of operation in the F.R.G. result in variations up to 15 per cent in the solar output. A sensitivity study was also done with respect to all solar collector, systems and user parameters. From this it was found that the dominant effects on the systems performance were due to the collector-dependent parameters.  相似文献   
30.
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