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1.
本文对1—5岁汉族儿童使用双宾结构的状况进行了考察。首先对儿童语言中双宾结构的结构类型、句法功能及其发展状况进行了描述分析;在此基础上,讨论了儿童习得汉语双宾结构的机制。  相似文献   
2.
本项研究旨在探索 5 -1 1岁儿童元认知发展的规律 ,2 80名昆明市及路南县汉、撒尼族儿童参与了三项知觉实验 ,实验结果表明 :1儿童随年龄的增长 ,有关知觉组织策略的知识及自我监察的能力也逐渐发展 ,表现为系统观察、选取有效策略及计划性的增强。 2儿童对信息的加工不断深入 ,从表浅的加工过渡到详尽的加工 ,不仅要求补充必要的信息 ,而且主动搜索隐蔽的线索以促进识辨。3儿童自我评价从笼统、含糊逐渐向客观、全面发展。4路南儿童元知觉的发展晚于昆明儿童两年 ,但在路南的汉族儿童和撒尼族儿童之间不存在显著差异 ,说明文化教育对儿童元知觉发展的重要影响。  相似文献   
3.
Spontaneous startles have been reported to occur most frequently in quiet sleep, less frequently in active sleep and drowse, and relatively nonexistent in the waking states. These findings may be a result of a focus on infants whose prenatal histories reflect a restricted range of the conditions to which normal newborns are exposed. The present study examined the spontaneous startle behavior of 30 newborn infants characterized by high numbers of obstetric complications and by indicators of prenatal malnutrition, but within the range of normal, healthy newborns. In this sample, startles were not limited to the sleep and drowse states. Because individual differences in a number of neonatal behaviors have been related to autonomic nervous system (ANS) functioning, the different pattern of spontaneous startles observed in this sample may be related to the functional integrity of this system.  相似文献   
4.
An alternating least squares method for iteratively fitting the longitudinal reduced-rank regression model is proposed. The method uses ordinary least squares and majorization substeps to estimate the unknown parameters in the system and measurement equations of the model. In an example with cross-sectional data, it is shown how the results conform closely to results from eigenanalysis. Optimal scaling of nominal and ordinal variables is added in a third substep, and illustrated with two examples involving cross-sectional and longitudinal data.Financial support by the Institute for Traffic Safety Research (SWOV) in Leidschendam, The Netherlands is gratefully acknowledged.  相似文献   
5.
This study investigated longitudinal relations between measures of neonatal state behavior and developmental outcome in a sample of preterm infants (N = 16). Results indicate that irritability/reactivity in the neonatal period is positively associated with Bayley scores and exploratory play at 8 months. Conversely, neonatal alertness was not associated with these developmental measures. These preliminary findings, based on a small sample, are discussed in the context of preterm function.  相似文献   
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基于工作要求-资源理论, 本研究探讨了两种社交媒体使用目的对员工工作绩效影响的内部作用机制, 进而分析两种社交媒体使用目的对员工工作绩效的影响效果。通过369份“领导者-下属”匹配数据, 研究发现:(1)基于工作、社交的社交媒体使用均促进员工工作绩效; (2)基于工作、社交的社交媒体使用均通过工作投入影响工作绩效, 基于社交的社交媒体使用还通过关系冲突影响工作绩效; (3)社交媒体的工作使用和社交使用对员工工作绩效的影响存在相互替代关系。本研究结果不仅从理论上拓展了社交媒体使用的研究视角, 为后续研究提供新的理论框架, 同时通过比较分析为组织管理社交媒体使用提供了新思路。  相似文献   
8.
Intraindividual variability is a fundamental behavioural characteristic of aging but has been examined to a very limited extent in driving. This study investigated intraindividual variability in driving simulator measures in healthy drivers of different ages using the coefficient of variation (COV) as a variability measure. Participants were healthy volunteers who were regular drivers, who were divided into a “young” group, a “middle-aged” group, and an “old” group. They drove in two environments (rural, 72 drivers; urban, 60 drivers), under conditions of moderate and high traffic load, without and with distraction (conversation). Significant differences in COV were observed in the rural condition for headway distance and lateral position as a function of traffic load, with high traffic (without and with distraction) resulting in increased COV of headway and decreased COV of lateral position. Significant differences in COV were observed in the urban condition for headway distance only, with high traffic (without and with distraction) resulting in increased COV of headway. No age effects were found for any of the driving conditions. The results indicate that traffic load affected headway distance and lateral position in opposite directions in all three age groups: high traffic resulted in increased variability of headway in both rural and urban conditions but in decreased variability of lateral position in the rural conditions compared to moderate traffic irrespective of distraction. The study indicates that driving conditions affect the intraindividual variability of driving measures in selective ways, which may be linked to the extent of automatization of the driving variables and to adaptive changes to traffic condition challenges.  相似文献   
9.
Traffic congestion and crash rates can be reduced by introducing variable speed limits (VSLs) and automatic incident detection (AID) systems. Previous findings based on loop detector measurements have revealed that drivers reduce their speeds while approaching traffic congestion when the AID system is active. Notwithstanding these behavioural effects, most microscopic traffic flow models assessing the impact of VSLs do not describe driver response accurately.This study analyses the main factors that influence driver deceleration behaviour while approaching traffic congestion with and without VSLs. The Dutch VSL database was linked to the driver behaviour data collected in the UDRIVE naturalistic driving study. Driver engagement in secondary tasks and glance behaviour were extracted from the video data. Linear mixed-effects models predicting the characteristics of deceleration events were estimated.The results show that the maximum deceleration is high when approaching a slower leader, when driving at high speeds and short distance headways, and close to the beginning of traffic congestion. The minimum time headway is short when driving at high speeds and changing lanes. Certain drivers showed higher decelerations and shorter time headways than others. Controlled for these main factors, smaller maximum decelerations were found when the VSLs were present and visible, and when the gantries were within close proximity. These factors could be incorporated into microscopic traffic simulations to evaluate the impact of AID systems on traffic congestion more realistically. Further research is needed to clarify the link between engagement in secondary tasks, glance behaviour and deceleration behaviour.  相似文献   
10.
Mental fatigue has been lacked attention in developing eye-tracking fatigue detection system for drivers. However, it has great influence on eye movement which could account for the poor validity of current fatigue detectors only focusing on sleep-related fatigue. This work sought to investigate the influence of two types of task-related mental fatigue on eye movement by examining 8 saccade-based, 3 blink-based, and 1 pupil-based metrics. We propose that two types of task-related fatigue caused by cognitive overload and prolonged underload will induce different physiological responses to eye-motion features. Twenty participants completed a vigilance task before and after a 1-h driving with a secondary task in a virtual simulation environment, while forty participants, divided equally into two groups, finished the same task before and after a 1-h and 1.5-h monotonous driving. T-test was applied to analyse the eye-motion, subjective and vigilance data during vigilance task. We found that overload driving made drivers vigilance ability decrease. The eye metrics showed different changes in underload and overload scenario. The blink duration, the mean velocity of saccade and saccade duration increased after 1-h overload driving, while the pupil diameter decreased. However, none of those changes were observed in 1.5-h underload driving, but saccade duration had a significant increase. The fatigue response to heavy demands over short periods of driving is different from the lighter demands over long periods in terms of eye-motion metrics. Considering mental fatigue in designing an eye-tracking fatigue detection system could possibly improve its accuracy.  相似文献   
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