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31.
Rinkenauer Gerhard; Osman Allen; Ulrich Rolf; Müller-Gethmann Hiltraut; Mattes Stefan 《Canadian Metallurgical Quarterly》2004,133(2):261
Lateralized readiness potentials (LRPs) were used to determine the stage(s) of reaction time (RT) responsible for speed-accuracy trade-offs (SATs). Speeded decisions based on several types of information were examined in 3 experiments, involving, respectively, a line discrimination task, lexical decisions, and an Erikson flanker task. Three levels of SAT were obtained in each experiment by adjusting response deadlines with an adaptive tracking algorithm. Speed stress affected the duration of RT stages both before and after the start of the LRP in all experiments. The latter effect cannot be explained by guessing strategies, by variations in response force, or as an indirect consequence of the pre-LRP effect. Contrary to most models, it suggests that SAT can occur at a late postdecisional stage. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
These studies investigated self-regulation and subjective experience of time from the perspective of the regulatory resource model. Studies 1-2 showed that participants who were instructed to regulate their emotions while viewing a film clip perceived that the film lasted longer than participants who did not regulate their emotions. In Study 3, participants provided time estimates during a resource-depleting or nondepleting task. Subsequent task persistence was measured. Time perceptions mediated the effect of initial self-regulation on subsequent self-regulated performance. In Study 4, participants performed either a resource-depleting or a nondepleting thought-listing task and then performed a different regulatory task. Compared with nondepleted participants, depleted participants persisted less on the 2nd task but estimated that they had persisted longer. Subjective time estimates statistically accounted for reduced persistence after depletion. Together, results indicate people believe that self-regulatory endeavors last overly long, a belief that may result in abandonment of further self-control. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
Verbruggen Frederick; Liefooghe Baptist; Vandierendonck André; Demanet Jelle 《Canadian Metallurgical Quarterly》2007,33(2):342
In the task-switching literature, it has frequently been demonstrated that although advance task preparation reduces the switch cost, it never really eliminates the switch cost. This remaining residual switch cost received much attention, and it has been argued that advance preparation is restricted in nature. In the present study, the role of task-cue presentation in the establishment of the residual switch cost was investigated. In 4 experiments, the cue was removed during the preparation interval, and it was hypothesized that this would encourage participants to complete advance task preparation. The results of all 4 experiments provided support for this hypothesis: When the cue was presented for a short time and then removed, the residual switch cost completely disappeared. This was found for different cue types. Furthermore, Experiment 3 demonstrated that it was not the presence of the cue itself but merely differences in advance task preparation that caused the effects. This suggests that advance task preparation is not as restricted in nature as previously assumed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
Hopko Derek R.; Hunt Melissa K.; Armento Maria E. A. 《Canadian Metallurgical Quarterly》2005,12(4):389
Anxious responding (trait, state, and test anxiety) has a negative impact on overt performance. Researchers have used a unidimensional method of assessing anxiety and performance, although a more informative approach would involve a comprehensive assessment battery and multiple performance tasks. Incorporating this strategy, the authors measured the impact of anxiety on 4 attentional processing tasks. Results revealed that "types" of anxiety symptoms were differentially related to attentional task performance; test anxiety accounted for the most variance in predicting performance on the Wechsler Adult Intelligence Scale-Third Edition (D. Wechsler, 1997) letter-number sequencing and digit-span subtests, trait anxiety and fear of negative evaluation were more significant in predicting Stroop performance, and math anxiety accounted for the largest variance toward understanding Paced Auditory Serial Addition Task (C. W. Lejuez, C. W. Kahler, & R. A. Brown, 2003) scores. Theoretical and clinical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
车辆实时监管正面临着不断增长的大规模车辆监测数据的实时处理需求,需要采用分布式的并行计算架构来提升大规模车辆监测数据处理的性能,支撑多样化的车辆监测数据处理任务,应对支撑环境的伸缩性需求。在这种架构下,对系统中不同计算节点间的车辆监测数据处理任务的调度提出了更高的要求。针对这一要求,并结合流式到达及历史积累的车辆监测数据的持续化处理需求以及大规模车辆监测数据实时处理中内存敏感的特征,提出一种基于路由表的并行任务调度算法。该算法基于车辆监测数据时空属性以及各计算节点的内存信息建立路由表,并以路由表的形式来进行任务的并行划分和分配调度,从而使得各计算节点达到负载均衡的状态。实验表明该算法能够使计算节点间的负载差异缩小到12%以内。此外,该算法在某市车辆监管实时系统中的实际应用也证明了其有效性。 相似文献
36.
《International Journal of Parallel, Emergent and Distributed Systems》2012,27(1-3):165-184
The purpose of this paper is to examine the impact of scheduling parallel tasks onto non-uniform memory access (NUMA) shared-memory multiprocessor systems by considering non-negligible intertask communications and communication contentions. Communication contentions arise from the communication medium having insufficient capacity to serve all transmissions, thereby causing significant contention delays. Therefore, a new scheduling algorithm, herein referred to as the Extended Critical Path (ECP) algorithm is proposed. The proposed algorithm schedules parallel tasks by considering non-negligible intertask communications and the contentions among shared communication resources. Moreover, it ensures performance within a factor of two of the optimum for general directed acyclic task graphs (DATGs). Experimental results demonstrate the superiority of the ECP algorithm over the scheduling algorithms presented in previous literature. 相似文献
37.
针对基于遗传算法的多机器人任务分配方法中,由于初始种群是随机产生不能很好地表征整个解空间,而容易陷入局部最优解的问题,提出一种新的多机器人任务分配方法。该方法根据机器人效用函数值来确定个体基因,从而产生初始种群,并引进分层遗传算法来实现具有不同最优基因的群体分开演化。仿真实验表明,该方法比传统的遗传算法有更高的寻优效率和更快的收敛速度。 相似文献
38.
任雪莲 《电脑编程技巧与维护》2012,(8):135-136
根据《Flash动画制作》课程在教学实践中的特点,提出构建"理实同步,实例引导,任务驱动"的教学模式,在教学内容、教学方法等方面进行教学改革,并阐述了在Flash教学中的具体实施方法,提高了学生动手能力及综合素质。 相似文献
39.
40.
针对卫星观测任务规划问题约束复杂、求解空间大和输入任务序列长度不固定的特点,使用深度强化学习(DRL)方法对卫星观测任务规划问题进行求解. 综合考虑时间窗口约束、任务间转移机动时间和卫星电量、存储约束,对卫星观测任务规划问题进行建模. 基于指针网络(PN)的运行机制建立序列决策算法模型,使用Mask向量来考虑卫星观测任务规划问题中的各类约束,并通过Actor Critic强化学习算法对模型进行训练,以获得最大的收益率. 借鉴多头注意力(MHA)机制的思想对PN进行改进,提出多头注意力指针网络(MHA-PN)算法. 根据实验结果可以看出,MHA-PN算法显著提高了模型的训练速度和泛化性能,训练好的MHA-PN算法模型可以直接对输入序列进行端到端的推理,避免传统启发式算法迭代求解的过程,具有较高的求解效率. 相似文献