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介绍基于 ISA(Industry Standard Architecture)总线的高码速度大容量遥测数据存储器的研究。作为计算机主存储设备的硬盘 ,它具有体积小 ,存储容量大的优点 ,本系统拟采用硬盘作为存储设备 ,且遥测数据在存储数据时采用脱线工作方式 ,我们设计了该存储器和计算机的接口且实现了对硬盘传输数据的 PIO(Program Input Output)方式的编程和对遥测数据的差错控制 相似文献
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Navigational aids impair spatial memory for experienced environments, but the cognitive mechanisms underlying impairment remain an open question. Recent evidence implicates divided attention, but to date no study has directly manipulated divided attention in navigational aid contexts. The present study addresses this need. Participants navigated virtual towns with aid presence and divided attention factorially crossed in a within-participants design. They then completed spatial memory assessments. Divided attention alone impaired spatial memory. Navigational aid presence impaired spatial memory when attention was undivided, replicating previous findings, but did not to a greater extent when attention was divided. These findings suggest that navigational aids divide attention sufficiently to impair spatial memory. 相似文献
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ABSTRACTThe ability to mentally represent spatial information is a fundamental cognitive process. To many people, this process feels a bit like visual perception, hence the term ‘spatial visualization’. In this paper, we describe a method for measuring the accuracy of spatial visualization, specifically visualization of a complex path in imaginary space. A critical feature of this method (called Path Visualization) is that it relies on the detection of intersections in a visualized path. Intersection detection is an inherently spatial task that requires a spatial representation. In this paper, we show how the Path Visualization method works, and how it can be customized to address several key research issues in human spatial cognition. 相似文献
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Abstract The present work explores an interactive model of spatial and temporal information in map memory. In four experiments, participants learned a map with temporal and spatial information confounded or unconfounded. Attentional and representational levels of information were made apparent through tasks that tap spatial, temporal, or other information. Learning criteria emphasizing sequential order or location imposed differential weighting of the information types in memory. Results indicate that map memory is spatial, but also interacts with the order in which map locations are encountered. Findings show flexibility in allocating attention and information indexing of location and sequential order information in map learning. 相似文献
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Although the physical organization of spatialinformation clearly influences how it is recognized,recalled, and mentally transformed, few studies haveexplored how different levels of organizationinteract. This study focused on 4- and 6-year-oldchildren's memory for spatial configurations andexamined the relative influence of two levels oforganization: symmetry (vertical, horizontal, or none)and codability (verbal or nonverbal). We predictedthat the influence of symmetry would be lesspronounced among the older children for whom thepatterns were more codable. The results partiallysupported this prediction: Older children'sreconstructions were accurate regardless of patternsymmetry; younger children's reconstructions ofvertically-symmetric patterns were more accurate thantheir reconstructions of horizontally-symmetric andasymmetric patterns. Taken together, the resultsrevealed an interaction between age and symmetry onthe accuracy of children's reconstructions, suggestingthat younger children were more sensitive than olderchildren to differences in pattern symmetry. Thus,different levels of organization may influencechildren's ability to recall spatial information andthe relative influence of these levels may changeduring development. 相似文献
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将多台计算机连接起来,共同完成单个的实时任务,如飞机仿真是一项非常具有挑战性的工程任务。本文论述了计算机分布式仿真的一些独特要求,对目前使用的两种主要方法进行了总结,将共享内存网的概念和传统的方法进行了对比介绍,共享内存网的设计方法、性能参数以及详细的设计过程也有论述。 相似文献
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前言钱学森同志是我所崇敬的学长和挚友,我们在学生时代有共同的学习目标和共同的在音乐和摄影艺术方面的爱好,这就加深了我们之间的友谊。此文是献给我们在学习时代,以及于十六年后在他克服了重重困难回到祖国,并做出了重大贡献时代之间的友谊,以为纪念。 相似文献
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当在内存中存储数据时,常常需要在运行时调整内存的大小,vector提供了一个安全、简易并且自动化的内存分配技术。基于时间效率、空间利用率方面的考虑,提出了几种修改内存增长机制的方法,并在此基础上,结合实际应用进行分析,从时间效率和空间利用率两方面对不同内存增长机制进行了比较,得出在实际应用中根据实际情况调整内存增长机制... 相似文献