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991.
水利水电工程土石方开挖可视化设计方法初探 总被引:6,自引:0,他引:6
土石方开挖是施工组织设计中的重要组成部分,它对土石方工程的概预算、施工的进度安排以及土石方工程填挖平衡的设计都有很大的影响。传统的土石方设计方法由于平面地形图可视性差以及求各网格点高程值的烦琐性,使得这项工作量很大,并且有时会因为网格划分的不合理,而产生较大的误差。为此,本提出土石方开挖的可视化设计方法,该方法弥补了传统方法的不足,能够很好地满足设计需要;同时,计算结果提供的土石方开挖后形态仿真图,能够呈现不同项目、开挖部位及断面特征(坡度),可以为组织开挖工程设计提供可视化决策信息。 相似文献
992.
Neglect is an acquired cognitive disorder characterized by a lack of processing of one side of a stimulus or representational space. There are hemispheric asymmetries in its cause and in its effects, but implemented computational models of neglect have tended not to incorporate this fact. The authors report a series of neural network simulations of the line-bisection task. They test the hypothesis that simple, neuroanatomically realistic principles of connectivity in the nervous system can produce emergent behaviors that capture a wide range of quantitative and qualitative data observed in neglect patients presenting with general visuospatial neglect. They demonstrate that exploring low-level architectural principles in implemented computational models is both a productive avenue of research and offers the most parsimonious explanations of behaviors observed in patients. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
993.
Miltner Wolfgang H. R.; Krieschel Silke; Hecht Holger; Trippe Ralf; Weiss Thomas 《Canadian Metallurgical Quarterly》2004,4(4):323
Spider-phobic and nonphobic subjects searched for a feared/fear-relevant (spider) or neutral target (mushroom) presented in visual matrices of neutral objects (flowers). In half of the displays, the mushroom target was paired with a spider distractor, or a spider target was paired with a mushroom distractor. Although all subjects responded faster to the neutral target than to the feared/fear-relevant target, phobics were slower to respond than nonphobics when a mushroom target was presented with a spider distractor. Their eyes appeared to be drawn to the feared distractor before fixating neutral targets. A further experiment indicated no group differences when subjects merely judged the homogeneity of matrices. Thus, threat seems to capture the attention of phobics only when it is part of a background that subjects are explicitly instructed to ignore. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Hebrew and Arabic are Semitic languages with a similar morphological structure and orthographies that differ in visual complexity. Two experiments explored the interaction of the characteristics of orthography and hemispheric abilities on lateralized versions of a letter-matching task (Experiment 1) and a global-local task (Experiment 2). In Experiment 1, native Hebrew readers and native Arabic readers fluent in Hebrew matched letters in the 2 orthographies. The results support the hypothesis that Arabic orthography is more difficult than Hebrew orthography for participants who can read both languages and that this difficulty has its strongest effects in the left visual field. In Experiment 2, native Arabic speakers performed a global-local letter detection task with Arabic letters with 2 types of inconsistent stimuli: different and similar. The results support the hypothesis that the right hemisphere of skilled Arabic readers cannot distinguish between similar Arabic letters, whereas the left hemisphere can. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Ragozzino Michael E.; Adams Spencer; Kesner Raymond P. 《Canadian Metallurgical Quarterly》1998,112(4):747
Reports an error in "Differential involvement of the dorsal anterior cingulate and prelimbic-infralimbic areas of the rodent prefrontal cortex in spatial working memory" by Michael E. Ragozzino, Spencer Adams and Raymond P. Kesner (Behavioral Neuroscience, 1998[Apr], Vol 112[2], 293-303). Figure 1 (page 295) and Figure 4 (page 299) were printed incorrectly. The corrected figure pages and corresponding captions are provided in the erratum. (The following abstract of the original article appeared in record 1998-01023-003.) The present study examined the effects of quinolinic acid lesions of the dorsal anterior cingulate and prelimbic-infralimbic cortices on spatial working memory and spatial discrimination using go/no-go procedures. All testing occurred in a 12-arm radial maze. In a working memory task, rats were allowed to enter 12 arms for a cereal reward. Three or 4 arms were presented for a 2nd time in a session, which did not result in a reward. In a spatial discrimination task, rats had successive access to 2 different arms. One arm always contained a reward, and the other never contained a reward. Prelimbic-infralimbic lesions impaired spatial working memory but only produced a transient spatial discrimination deficit. Dorsal anterior cingulate lesions did not induce a deficit in either task. These findings suggest that the prelimbic-infralimbic cortices, but not the anterior cingulate cortex, are important in spatial working memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
In a series of 5 experiments, the allocation of attention prior to the execution of saccade sequences was examined by using a dual-task paradigm. In the primary task, participants were required to execute a sequence of 2 endogenous saccades. The secondary task was a forced-choice letter identification task. During the programming of the saccade sequences, letters were briefly presented at the saccade goals and at no-saccade locations. The results showed that performance was better for letters presented at any of the saccade goals than for letters presented at any of the no-saccade locations. The results support a spatial model that assumes that prior to the execution of a saccade sequence, attention is allocated in parallel to all saccade goals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Slaughter Jerel E.; Sinar Evan F.; Bachiochi Peter D. 《Canadian Metallurgical Quarterly》2002,87(2):333
This study examined the effects of plan content and previous experience with discrimination on Black respondents' reactions to affirmative action plans. Black engineering students (N=1,173) were randomly assigned to 1 of 6 plans implemented by a hypothetical organization and were asked to provide ratings of perceived fairness and intention to pursue a position at the organization. There were significant effects of plan content on perceived fairness and job pursuit intentions, Perceived fairness mediated the effect of content on intentions. Furthermore, previous experience with discrimination interacted with content to affect intentions. Individuals who had experienced relatively more discrimination in the workplace reported stronger intentions to pursue a position at an organization whose plan specified special training opportunities for minorities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Five experiments investigated the types of changes that disrupt the preview effect--the benefit gained in difficult search tasks from presenting some distractors earlier in time. A shape change with or without an overall luminance change at the location of an old item was found to disrupt the preview effect, whereas an equivalent luminance change alone or an isoluminant color change was not disruptive. Results suggest that (a) relatively low-level visual changes may not be sufficient to abolish the benefit, (b) the benefit most likely occurs through inhibition applied to locations within a location master map, and (c) inhibition need not be applied to surface features of objects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
The present study aimed to assess the effects of aging and awareness on conditional discrimination learning within an eyeblink conditioning procedure by using a consecutive age-groups design (20-35 years, 36-50 years, 51-65 years, 66-80 years). Increasing age was associated with a decline in overall eyeblink conditioned response (CR) frequency and a deficit in conditional discrimination learning in the 2 older groups. Awareness of stimulus contingencies affected discrimination performance but not overall CR rates in younger subjects. Older subjects did not achieve eyeblink conditional discrimination learning, regardless of awareness. Discrimination performance correlated with measures of declarative memory. The pattern of results is discussed with respect to the involvement of hippocampal-cerebellar interactions and awareness in the mediation of age-related conditioning changes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
探讨了如何利用Visual Foxpro6.0的MSComm32控件来实现windows98环境下的串行通讯,并通过一个通信程序实例详细介绍了该控件的使用方法. 相似文献