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101.
Recent research indicates that by 4.5 months, infants use shape and size information as the basis for individuating objects but that it is not until 11.5 months that they use color information for this purpose. The present experiments investigated the extent to which infants' sensitivity to color information could be increased through select experiences. Five experiments were conducted with 10.5- and 9.5-month-olds. The results revealed that multimodal (visual and tactile), but not unimodal (visual only), exploration of the objects prior to the individuation task increased 10.5-month-olds' sensitivity to color differences. These results suggest that multisensory experience with objects facilitates infants' use of color information when individuating objects. In contrast, 9.5-month-olds did not benefit from the multisensory procedure; possible explanations for this finding are explored. Together, these results reveal how an everyday experience--combined visual and tactile exploration of objects--can promote infants' use of color information as the basis for individuating objects. More broadly, these results shed light on the nature of infants' object representations and the cognitive mechanisms that support infants' changing sensitivity to color differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
知识经济的发展,使知识和创新,成为人类活动的强大动力,人类的实践活动迈入了崭新阶段。人类的潜在智慧和才能,正源源不断地释放出来,转化为对象性存在,充分展示了人类活动的主体性效应,与此同时我们也必须正视人类活动的反主体性的效应。正确处理主体自觉能动性和客体自然性之间矛盾,是强化人类活动的主体性效应,防止反主体性效应的前提条件。  相似文献   
103.
In a change detection paradigm, a target object in a natural scene either rotated in depth, was replaced by another object token, or remained the same. Change detection performance was reliably higher when a target postcue allowed participants to restrict retrieval and comparison processes to the target object (Experiment 1). Change detection performance remained excellent when the target object was not attended at change (Experiment 2) and when a concurrent verbal working memory load minimized the possibility of verbal encoding. (Experiment 3). Together, these data demonstrate that visual representations accumulate in memory from attended objects as the eyes and attention are oriented within a scene and that change blindness derives, at least in part, from retrieval and comparison failure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
104.
文章介绍一种自行研制的玻璃自动切割机开放式计算机控制系统,并针对该切割机加工范围大、惯性大、动态精度要求高等特点,研究了一种智能适应型PID控制算法。现场测试表明,该系统在功能、性能和控制精度上达到或接近国外同类产品的先进水平,在系统硬件和软件的开放性上优于国外产品。文中详细介绍了该计算机控制系统的功能、系统设计、控制算法及其调试结果。  相似文献   
105.
In 3 experiments, 9-month-old infants' expectations for what distinct count noun labels refer to were investigated. In Experiment 1, a box was opened to reveal 2 objects inside during familiarization: either 2 identical objects or 2 different objects. Test trials followed the same procedure, except before the box was opened, the contents were described using 2 distinct labels ("I see a wug! I see a dak!") or the same label twice ("I see a zav! I see a zav!"). Infants who heard a label repeated twice looked longer at 2 different objects versus 2 identical objects, whereas infants who heard 2 distinct labels showed a different pattern of looking. Experiments 2 and 3 presented infants with object pairs that only differed in shape or color, and it was found that infants expected the different-shaped (but not the different-colored) objects to be labeled by distinct count nouns. Because the property of shape is a cue to kind membership and the property of color is not, these results suggest that even at the beginning of word learning, infants may expect distinct labels to refer to distinct kinds of objects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
106.
针对压缩视频流中的误码,提出了一种新颖的基于对象几何形状的视频抗误码方法.首先,在编码端通过比较帧间编码帧内邻近宏块的运动向量差异获得粗略的对象几何形状信息,以对象标示图表示;再把它以与标准码流兼容的方式嵌入到压缩码流里去;最后,在解码端利用它帮助精确的构造错误宏块的运动向量.试验结果表明,该方法对于即使大量连续slice出错的情况仍能获得比较好的掩盖效果,而增加的运算复杂度和传输负载量都不大.  相似文献   
107.
对象模型及其模型化方法——一种深知识的表示模型   总被引:6,自引:0,他引:6  
本文介绍了对象模型和深知识等概念,在这些概念的基础上还讨论了基于框架知识表示形式的复杂系统的模型化方法.文中给出的模型化方法是通过 ISA 关系和 PART-OF 关系的相结合而形成的.这种模型化方法可用于基于深知识的设计型、分析型以及控制型等类型的专家系统.  相似文献   
108.
Although brushless resolvers have been used widely as angular position transducers, they are expensive due to their intricate construction, involving a rotary transformer to supply the exciting coils wound on the rotor poles with the current. It is shown theoretically in this paper that the resolver without rotary transformer or brushes can be realized by simple construction, which consists of the stator core with both 4-poles exciting windings and 2-poles output ones and the rotor core carrying no windings. In this resolver the rotor core has minimum gap at one side and a maximum gap at another side of the diameter. It is characterized by an outer surface form that makes the fluctuation part of gap permeance very in proportion to cos θ, where θ represents the angular position of a point in the air gap with respect to the origin on the rotor, the point of minimum air gap. The method determining the rotor form to embody the aforementioned gap permeance variation is also shown. It has been confirmed not only by simulation but also experiment that the 2-phase output voltages of a model designed based on the theory have sinusoidal waveforms with very small harmonic contents. Moreover, the rotor position detected by processing the output voltages through the conventional resolver/digital converter was within acceptable engineering accuracy.  相似文献   
109.
智能网(IN)的概念于1984年一被提出,便在世界范围内迅速掀起了IN研究的热潮,虽然至今已有十个年头,但仍可以说,IN技术的发展才刚刚起步。本文就是基于当前国际上对IN的研究,来介绍智能网的基本概念和结构,进而阐述其设计思想及主要特征,并对IN的未来发展趋势进行了探讨,最后为我国发展IN技术提出了可行建议。  相似文献   
110.
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