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91.
A. Pollatsek, E. D. Reichle, and K. Rayner (see record 2006-22004-014) argue that the critical findings in A. W. Inhoff, B. M. Eiter, and R. Radach (see record 2005-13471-012) are in general agreement with core assumptions of sequential attention shift models if additional assumptions and facts are considered. The current authors critically discuss the hypothesized time line of processing and indicate that the success of Pollatsek et al.'s simulation is predicated on a gross underestimation of the pretarget word's viewing duration in Inhoff et al. and that the actual data are difficult to reconcile with the strictly serial attention shift assumption. The authors also discuss attention shifting and saccade programming assumptions in the E-Z Reader model and conclude that these are not in harmony with research in related domains of study. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Douglas Douglas 《Computers and the Humanities》1992,26(5-6):331-345
The present paper summarizes the major methods and results of the multi-dimensional approach to genre variation. The approach combines the resources of computational tools, large text corpora, and multivariate statistical tools (such as factor analysis and cluster analysis). It has been used to address issues such as the relations among spoken and written genres in English, and the historical development of genres and styles. The approach has also been applied to other languages; in this regard it has been used to address broader theoretical issues, such as the extent to which genre, and style variation are comparable cross-linguistically, and the linguistic consequences of literacy.Douglas Biber is an associate professor in the Department of English, Applied Linguistics Program, Northern Arizona University, Flagstaff AZ. His research deals with the linguistic variation among registers and the diachronic evolution of registers, addressing both theoretical concerns and methodological issues relating to the design and use of computer-based text corpora. 相似文献
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James I. Mitchell-White Thomas Stockner Nicholas Holliday Stephen J. Briddon Ian D. Kerr 《International journal of molecular sciences》2021,22(6)
The five members of the mammalian G subfamily of ATP-binding cassette transporters differ greatly in their substrate specificity. Four members of the subfamily are important in lipid transport and the wide substrate specificity of one of the members, ABCG2, is of significance due to its role in multidrug resistance. To explore the origin of substrate selectivity in members 1, 2, 4, 5 and 8 of this subfamily, we have analysed the differences in conservation between members in a multiple sequence alignment of ABCG sequences from mammals. Mapping sets of residues with similar patterns of conservation onto the resolved 3D structure of ABCG2 reveals possible explanations for differences in function, via a connected network of residues from the cytoplasmic to transmembrane domains. In ABCG2, this network of residues may confer extra conformational flexibility, enabling it to transport a wider array of substrates. 相似文献
96.
现有算法难以处理脉冲噪声,导致无线传感器网络(WSN)中节点定位精度较低,为此提出基于Bregman散度的WSN定位算法. 该算法分为2个阶段:欧氏距离矩阵(EDM)恢复阶段和坐标映射阶段. 基于EDM的自然低秩性,将EDM恢复问题转化为噪声环境下的矩阵补全问题;采用L1,2范数显式平滑脉冲噪声,建立正则化矩阵补全模型;为了有效求解该模型,定义多元函数Bregman散度,将分裂Bregman迭代拓展到矩阵空间,结合交替最小化算法,得到EDM的估计;在此基础上,基于多维标度法对节点位置进行估计. 实验结果表明,在不同噪声条件下,该算法在保证高效性的同时,在定位精度和鲁棒性方面优于其他算法,特别是当采样率达到一定程度时,定位误差不到其他算法的1/4. 相似文献
97.
Galina V. Paramei Yulia A. Griber Dimitris Mylonas 《Color research and application》2018,43(3):358-374
Russian color naming was explored in a web‐based experiment. The purpose was 3‐fold: to examine (1) CIELAB coordinates of centroids for 12 Russian basic color terms (BCTs), including 2 Russian terms for “blue”, sinij “dark blue”, and goluboj “light blue”, and compare these with coordinates for the 11 English BCTs obtained in earlier studies; (2) frequent nonBCTs; and (3) gender differences in color naming. Native Russian speakers participated in the experiment using an unconstrained color‐naming method. Each participant named 20 colors, selected from 600 colors densely sampling the Munsell Color Solid. Color names and response times of typing onset were registered. Several deviations between centroids of the Russian and English BCTs were found. The 2 “Russian blues”, as expected, divided the BLUE area along the lightness dimension; their centroids deviated from a centroid of English blue. Further minor departures were found between centroids of Russian and English counterparts of “brown” and “red”. The Russian color inventory confirmed the linguistic refinement of the PURPLE area, with high frequencies of nonBCTs. In addition, Russian speakers revealed elaborated naming strategies and use of a rich inventory of nonBCTs. Elicitation frequencies of the 12 BCTs were comparable for both genders; however, linguistic segmentation of color space, employing a synthetic observer, revealed gender differences in naming colors, with more refined naming of the “warm” colors from females. We conclude that, along with universal perceptual factors, that govern categorical partition of color space, Russian speakers’ color naming reflects language‐specific factors, supporting the weak relativity hypothesis. 相似文献
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99.
《水科学与水工程》2022,15(2):103-113
Anomalous characteristics of the atmospheric water cycle structure are highly significant to the mechanisms of seasonal-scale meteorological droughts. They also play an important role in the identification of indicative predictors of droughts. To better understand the causes of seasonal meteorological droughts in the middle and lower reaches of the Yangtze River (MLRYR), characteristics of the atmospheric water cycle structure at different drought stages were determined using standardized anomalies. The results showed that the total column water vapor (TCWV) was anomalously low during drought occurrence periods. In contrast, there were no anomalous signals at the drought persistence and recovery stages in the MLRYR. Moreover, there was no significant temporal correlation between the TCWV anomaly and seasonal-scale drought index (the 3-month standardized precipitation index (SPI3)). During drought events, water vapor that mainly originated from the Bay of Bengal was transported southwest of the MLRYR. Meanwhile, the anomalous signal of water vapor transport was negative at the drought appearance stage. At the drought persistence stage, the negative anomalous signal was the most significant. Water vapor flux divergence in the MLRYR showed significant positive anomalous signals during drought events, and the signal intensity shifted from an increasing to a decreasing trend at different drought stages. In addition, a significant positive correlation existed between the anomaly of water vapor flux divergence and regional SPI3. Overall, water vapor flux divergence is more predictive of droughts in the MLRYR. 相似文献
100.
Crossing experiments between two closely related moths, Ostrinia scapulalis and O. zealis, were conducted to gain insight into the genetic basis of the divergence of female sex pheromones. The sex pheromone of O. scapulalis comprises (E)-11- and (Z)-11-tetradecenyl acetates (E11 and Z11), and distinct genetic variation is found in the blend of components. This variation is largely controlled by a single autosomal locus with two alleles, AE(sca) and AZ(sca). E-type (AE(sca)AE(sca)) females produce a pheromone with amean E11:Z11 ratio of 99:1, whereas Z-type (AZ(sca)AZ(sca)) and I-type (AE(sca)AZ(sca)) females produce a pheromone with a mean of 3:97 and 64:36, respectively. O. zealis is distinctive in that it has a third pheromone component, (Z)-9-tetradecenyl acetate (Z9), in addition to E11 and Z11, and the typical blend ratio is 60:35:5 (Z9:E11:Z11). Our study revealed that Z9 production in O. zealis is mainly regulated by an autosomal recessive gene phr(zea), which is suggested to be involved in the chain-shortening of a pheromone precursor fatty acid, and linked to AE(zea), a gene corresponding to AE(sca) in O. scapulalis. A few mutations in a gene involved in pheromone production could explain the dramatic shift between a two-component pheromone communication system in O. scapulalis and a three-component system in O. zealis. 相似文献