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McKenna Frank P.; Horswill Mark S.; Alexander Jane L. 《Canadian Metallurgical Quarterly》2006,12(1):1
Skill and risk taking are argued to be independent and to require different remedial programs. However, it is possible to contend that skill-based training could be associated with an increase, a decrease, or no change in risk-taking behavior. In 3 experiments, the authors examined the influence of a skill-based training program (hazard perception) on the risk-taking behavior of car drivers (using video-based driving simulations). Experiment 1 demonstrated a decrease in risk taking for novice drivers. In Experiment 2, the authors examined the possibilities that the skills training might operate through either a nonspecific reduction in risk taking or a specific improvement in hazard perception. Evidence supported the latter. These findings were replicated in a more ecological context in Experiment 3, which compared advanced and nonadvanced police drivers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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该文分析了应用袋装炸药装填水孔爆破产生拒爆、"冲天炮"、根底偏高和爆破效果差等问题,然而应用乳化炸药混装车装填水孔可以解决这些问题,并且爆破后具有根底平整、大块率低、毒气少和综合效益高等优点.以三峡永久船闸旁侧泄水箱涵工程和江苏田湾核电站工程为例进行了分析. 相似文献
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主要作为电子高科技的重点领域,专用实时设备无论类别和型号,抑或数量和质量,均与日俱增,令人目不暇接。它们的高效管理与灵活加接,是任何计算机专用实时系统不可或缺的基本功能,其驱动模块随之成为任何专用实时系统无法回避的设计难点。本文介绍我们自行研制的专用实时设备驱动程序交互式生成器RTDG的设计与实现。 相似文献
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Rajesh R. Shrestha Barrie R. Bonsal Ashish Kayastha Yonas B. Dibike Christopher Spence 《Journal of Great Lakes research》2021,47(3):677-689
This study assesses snow response in the Assiniboine-Red River basin, located in the Lake Winnipeg watershed, due to anthropogenic climate change. We use a process-based distributed snow model driven by an ensemble of eight statistically downscaled global climate models (GCMs) to project future changes under policy-relevant global mean temperature (GMT) increases of 1.0 °C to 3.0 °C above the pre-industrial period. Results indicate that basin scale seasonal warmings generally exceed the GMT increases, with greater warming in winter months. The majority of GCMs project wetter winters and springs, and drier summers, while autumn could become either drier or wetter. An analysis of snow water equivalent (SWE) responses under GMT changes reveal higher correlations of snow cover duration (SCD), snowmelt rate, maximum SWE (SWEmax) and timing of SWEmax with winter and spring temperatures compared to precipitation, implying that these variables are predominantly temperature controlled. Consequently, under the GMT increases from 1.0 °C to 3.0 °C, the basin will experience successively shorter SCD, slower snowmelt, smaller monthly SWE and SWEmax, earlier SWEmax, and a transition from snow-dominated to rain-snow hybrid regime. Further, while the winter precipitation increases for some GCMs compensate the temperature-driven changes in SWE, the increases for most GCMs occur as rainfall, thus limiting the positive contribution to snow storage. Overall, this study provides a detailed diagnosis of the snow regime changes under the policy-relevant GMT changes, and a basis for further investigations on water quantity and quality changes. 相似文献
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包建华 《计算机测量与控制》2012,20(3):702-704
设计了一种分层式的步进电机控制系统,现场控制层以AT89C52单片机为主控芯片,通过软件编程实现对步进电机的启停、正反转及调速控制,上位机监控层在工控组态软件MCGS平台下开发,操作界面直观友好,可以方便地对现场步进电机控制系统发布控制命令和参数;为解决现场控制层与监控层间数据交互问题,开发了基于MCGS的51单片机驱动构件;实际运行结果表明,整个系统实时性、稳定性良好,完全达到设计要求。 相似文献
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介绍了轻、中型卡车纵梁及车厢边框加工新型数控冲孔生产线的结构、性能特点.生产线可实现卡车底盘纵梁及车厢边框的冲制,具有精度高、生产周期短、灵活性强等优点,并可大大减少生产环节的库存量. 相似文献
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《矿业科学技术学报(英文版)》2016,26(5):745-752
Data collected from truck payload management systems at various surface mines shows that the payload variance is significant and must be considered in analysing the mine productivity,energy consumption,greenhouse gas emissions and associated cost.Payload variance causes significant differences in gross vehicle weights.Heavily loaded trucks travel slower up ramps than lightly loaded trucks.Faster trucks are slowed by the presence of slower trucks,resulting in‘bunching’,production losses and increasing fuel consumptions.This paper simulates the truck bunching phenomena in large surface mines to improve truck and shovel systems’efficiency and minimise fuel consumption.The study concentrated on completing a practical simulation model based on a discrete event method which is most commonly used in this field of research in other industries.The simulation model has been validated by a dataset collected from a large surface mine in Arizona state,USA.The results have shown that there is a good agreement between the actual and estimated values of investigated parameters. 相似文献
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