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A series of experiments introduced interruptions to the execution phase of simple Tower of London problems and found that the opportunity for preparation before the break in task reduced the time cost at resumption. Retrieval of the suspended goal was facilitated when participants were given the opportunity to encode retrieval cues during an "interruption lag" (the brief time before engaging in the interrupting task) but was impeded when these visual cues were subsequently altered following interruption. The results provide useful support for the goal-activation model (E. M. Altmann & G. J. Trafton, 2002), which assumes that context--at the points of both goal suspension and goal retrieval--is critical to efficient interruption recovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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潘锦华 《特种铸造及有色合金》2005,25(11):689-691
介绍了五台山铜塔铸造工艺,由于其结构特殊,故采用了3种工艺分别铸造而成:细砂湿模造型、树脂砂毁模贴皮造型和熔模铸造.介绍了铜塔表面化学着色技术.铜塔铸造工艺对其他相似艺术铸品具有一定的借鉴价值. 相似文献
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受全球气候变暖的影响,“中华水塔”地区正面临着以“变暖变湿”为主的气候变化。受气候及下垫面条件的综合影响,区域水资源显著增加,各流域产流机理在空间上呈现出明显的地区差异特征。基于“中华水塔”区域1956—2020年水文气象资料,通过趋势、突变、距平等分析方法,分析其水文要素和产流规律的变化趋势、特征及相互之间影响关系。结果表明:近年来“中华水塔”区域气温显著升高,蒸发能力总体增强,区域进入丰水期,降水、径流显著增加,在同等降水径流尺度下,黄河源区产流能力有所降低,长江、澜沧江源区产流能力明显增强;气温升高、降水量持续偏丰以及流域前期影响雨量(蓄水量)增加、枯季径流比例提高、下垫面生态持水能力增强是引起区域产流规律变化、水资源量增加的主要原因。 相似文献
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在对比国内外冷却塔填料现场应用情况的基础上,总结了Impac塔填料及喷嘴应用的优势及存在的问题,说明了Impac塔填料热力性能传质传热效果及Lantc喷头的布水情况,通过经济效益对比分析表明,该填料及喷头具有良好的应用前景;同时,该填料具有施工安装方便等特点,对解决冷却塔冬季结冰也有好处,为冷却塔改造填料喷嘴的选型提供了新途径。 相似文献
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《Advanced Engineering Informatics》2014,28(4):287-296
In recent years, information and sensing technologies have been applied to the construction industry to collect and provide rich information to facilitate decision making processes. One of the applications is using location data to support autonomous crane safety monitoring (e.g., collision avoidance and dangerous areas control). Several location-aware wireless technologies such as GPS (Global Positioning System), RFID (Radio-frequency identification), and Ultra-Wide Band sensors, have been proposed to provide location information for autonomous safety monitoring. However, previous studies indicated that imperfections (errors, uncertainty, and inconsistency) exist in the data collected from those sensors and the data imperfections have great impacts on autonomous safety monitoring system performance. This paper explores five computationally light-weight approaches to deal with the data imperfections, aiming to improve the system performance. The authors built a scaled autonomous crane safety monitoring testbed with a mounted localization system to collect location data and developed five representative test cases based on a live construction jobsite. Seven hundred and sixty location readings were collected at thirty-eight test points from the sensors. Those location data was fed into the reasoning mechanisms with five approaches to generate the safety decisions at those thirty-eight test points and evaluate system performance in terms of precision, recall and accuracy. The results indicate that system performance can be improved if at least ten position readings from sensors can be collected at small intervals at any location along the moving path. However, by including additional data such as velocity and acceleration that may be read from devices mounted on workers, localization error may be significantly reduced. These findings represent a path forward to improve localization accuracy by mixing imperfect data from the sensed environment with supplemental input. 相似文献
9.
William K. McGrane Ph.D. 《臭氧:科学与工程》1992,14(3):231-244
This paper builds on a prior paper by this author, McGrane (1991). In that paper, ozone is used as the sole means of cooling tower water treatment. The paper discusses water conservation by increased cycles of concentration, greatly increased efficiency through extremely low biological populations, and corrosion data which is compared to ozonated and chemically treated towers.
New in this paper are the results from the combination of a low pressure reverse osmosis system with ozone treatment for cooling tower water. Scale formation has continued to plague cooling towers with high concentrations of calcium in the make-up water. The use of a mineral removal system in cases of extremely hard water has made ozone an attractive alternative to traditional chemicals in many areas. 相似文献
10.
针对塔机防碰撞以缺乏灵活性和时实性的被动防御为主的现状,为实现智能化主动防碰撞的目的,通过分析障碍物轮廓与超声测距时间序列间的映射关系,以时间融合的思想引入Elman网络,并通过变形输入输出实现了单超声传感器由测距序列快速识别障碍物高精度位置信息的功能,并经试验验证可以达到预期低成本、快速度、高精度的塔机工作使用要求,也为低精度传感器获取高精度融合结果提出借鉴思路。 相似文献