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1.
Reading requires the orchestration of visual, attentional, language-related, and oculomotor processing constraints. This study replicates previous effects of frequency, predictability, and length of fixated words on fixation durations in natural reading and demonstrates new effects of these variables related to 144 sentences. Such evidence for distributed processing of words across fixation durations challenges psycholinguistic immediacy-of-processing and eye-mind assumptions. Most of the time the mind processes several words in parallel at different perceptual and cognitive levels. Eye movements can help to unravel these processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
The eye movements of young and older adults were tracked as they read sentences varying in syntactic complexity. In Experiment 1, cleft object and object relative clause sentences were more difficult to process than cleft subject and subject relative clause sentences; however, older adults made many more regressions, resulting in increased regression path fixation times and total fixation times, than young adults while processing cleft object and object relative clause sentences. In Experiment 2, older adults experienced more difficulty than young adults while reading cleft and relative clause sentences with temporary syntactic ambiguities created by deleting the that complementizers. Regression analyses indicated that readers with smaller working memories need more regressions and longer fixation times to process cleft object and object relative clause sentences. These results suggest that age-associated declines in working memory do affect syntactic processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Staub Adrian; Rayner Keith; Pollatsek Alexander; Hy?n? Jukka; Majewski Helen 《Canadian Metallurgical Quarterly》2007,33(6):1162
Readers' eye movements were monitored as they read sentences containing noun-noun compounds that varied in frequency (e.g., elevator mechanic, mountain lion). The left constituent of the compound was either plausible or implausible as a head noun at the point at which it appeared, whereas the compound as a whole was always plausible. When the head noun analysis of the left constituent was implausible, reading times on this word were inflated, beginning with the first fixation. This finding is consistent with previous demonstrations of very rapid effects of plausibility on eye movements. Compound frequency did not modulate the plausibility effect, and all disruption was resolved by the time readers' eyes moved to the next word. These findings suggest (contra Kennison, 2005) that the parser initially analyzes a singular noun as a head instead of a modifier. In addition, the findings confirm that the very rapid effect of plausibility on eye movements is not due to strategic factors, because in the present experiment, unlike in previous demonstrations, this effect appeared in sentences that were globally plausible. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Using the gaze-contingent boundary paradigm with the boundary placed after word n, the experiment manipulated preview of word n + 2 for fixations on word n. There was no preview benefit for 1st-pass reading on word n + 2, replicating the results of K. Rayner, B. J. Juhasz, and S. J. Brown (2007), but there was a preview benefit on the 3-letter word n + 1, that is, after the boundary but before word n + 2. Additionally, both word n + 1 and word n + 2 exhibited parafoveal-on-foveal effects on word n. Thus, during a fixation on word n and given a short word n + 1, some information is extracted from word n + 2, supporting the hypothesis of distributed processing in the perceptual span. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Ca-P仿生人工骨材料的设计与制备 总被引:2,自引:0,他引:2
本文设计了用磷酸钙生物陶瓷制备仿生人工骨的工艺路线 ,从原料合成、材料成型和烧结等讨论了仿骨材料的制备方法 相似文献
6.
The nanometer scale topography of self‐assembling structural protein complexes in animals is believed to induce favorable cell responses. An important example of such nanostructured biological complexes is fibrillar collagen that possesses a cross‐striation structure with a periodicity of 69 nm and a peak‐to‐valley distance of 4–6 nm. Bovine collagen type I was assembled into fibrillar structures in vitro and sedimented onto solid supports. Their structural motif was transferred into a nickel replica by physical vapor deposition of a small‐grained metal layer followed by galvanic plating. The resulting inverted nickel structure was found to faithfully present most of the micrometer and nanometer scale topography of the biological original. This nickel replica was used as a die for the injection molding of a range of different thermoplastic polymers. Total injection molding cycle times were in the range of 30–45 seconds. One of the polymer materials investigated, polyethylene, displayed poor replication of the biological nanotopographical motif. However, the majority of the polymers showed very high replication fidelity as witnessed by their ability to replicate the cross‐striation features of less than 5 nm height difference. The latter group of materials includes poly(propylene), poly(methyl methacrylate), poly(L ‐lactic acid), polycaprolactone, and a copolymer of cyclic and linear olefins (COC). This work suggests that the current limiting factor for the injection molding of nanometer scale topography in thermoplastic polymers lies with the grain size of the initial metal coating of the mold rather than the polymers themselves.
7.
针对驾驶员驾驶过程中因疲劳引起的眼睛开度变化问题, 在原有PERCLOS(percentage of eyelid closure over the pupil over time)标准的基础上, 提出了一种基于有限状态自动机的人眼开度PERCLOS计算方法, 并将其应用到疲劳驾驶预警系统中。该系统首先采用红外摄像头实时获取驾驶员的脸部视频图像, 使用ASM(active shape models)算法进行人脸检测, 在定位到的人脸范围内搜索人眼区域并计算人眼开度, 为了避免人与摄像头距离变化影响计算结果, 对人眼开度进行归一化处理; 然后依据建立的有限状态自动机模型计算PERCLOS值; 最后根据制定的预警机制实现基于人眼开度的疲劳预警。实验结果表明本方法能够实时监测驾驶员疲劳状况, 具有对光照变化、脸部配饰不敏感的特点。 相似文献
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9.
细胞色素P-450是一种生物体内催化分子氧氧化内源底物的单加氧酶,其活性片段的核心结构是金属卟啉络合物。人工合成的金属卟啉络合物可作为细胞色素P-450的有效模拟物,应用于烯烃、直链烷烃、环烷烃、芳烃、芳烃侧链、及各种杂原子等多种底物的催化氧化。人工合成的金属卟啉络合物可分为:对称型金属卟啉、非对称型金属卟啉、μ-氧代双核金属卟啉、负载型金属卟啉4大类。现以金属卟啉络合物的结构为线索,论述了结构与催化活性及稳定性的内在联系,重点介绍了近几年国内外金属卟啉仿生催化剂的氧化应用研究进展,及仿生催化氧化的工业化发展前景。 相似文献
10.
头皮脑电信号具有非平稳特性,相干等传统分析方法并不能很好地检测这些脑电时间序列间的依赖关系。广义同步中的似然同步算法对非平稳信号处理具有较好的效果,该文将它应用到实际脑电信号分析中。基于单向耦合Henon映射系统和实际脑电数据的仿真结果均表明,基于广义同步的似然同步方法适用测量非平稳信号间关系。针对健康被试静息态下,从闭眼到睁眼的过程中脑电信号间同步性的变化进行了研究,发现从闭眼到睁眼过程中,大脑的alpha波在几乎所有电极间的同步强度都显著地减弱,大脑的活动受到一定的抑制。上述结果也表明该方法在脑电数据分析中具有重要的意义,为其他的脑电研究提供一定的参考方法。 相似文献