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421.
王海波 《交通运输工程与信息学报》2008,6(4):76-81
驾驶员可靠性评估因子的选择是进行驾驶员可靠性评价的关键。本文首先进行驾驶员可靠性分析,找到驾驶员可靠性研究的特点,然后根据道路交通事故的发生原因得出驾驶员失误模式,最后使用专家判断隶属度的方法筛选出有效的驾驶员可靠性评估因子。 相似文献
422.
通过参数分析,对影响下承式系杆拱桥吊杆疲劳的直接因素,如吊杆的位置、吊杆的间距、边吊杆至拱脚的距离、吊杆截面积、吊杆的弯曲刚度、汽车冲击力等,以及一些间接因素进行了分析,并结合算例进行了应用。 相似文献
423.
陈荣华 《武汉船舶职业技术学院学报》2009,8(4):118-119,125
情感因素对于英语学习者,尤其是高职院校英语学习者,在学习过程中的能动作用日益显现,本文从情感角度浅论高职英语教学中教师如何充分运用情感因素激发学生内在潜力,从而让学生在学习中保持高昂的热情和快乐心境,提高学习效果。 相似文献
424.
ATCEM: a synthetic model for evaluating air traffic complexity 总被引:1,自引:0,他引:1
Air traffic complexity, which measures the disorder of air traffic distribution, has become the critical indicator to reflect air traffic controller workload in air traffic management (ATM) system. However, it is hard to assess the system accurately because there are too many correlated factors, which make the air traffic complexity nonlinear. This paper presents an air traffic complexity evaluation model with integrated classification using computational intelligence (ATCEM). To avoid redundant factors, critical factors contributing to complexity are analyzed and selected from numerous factors in the ATCEM. Subsequently, to construct the mapping relationship between selected factors and air traffic complexity, an integrated classifier is built in ATCEM. With efficient training and learning based on aviation domain knowledge, the integrated classifier can effectively and stably reflect the mapping relationship between selected factors and the category of air traffic complexity to ensure the precision of the evaluation. Empirical studies using real data of the southwest airspace of China show that the ATCEM outperforms a number of state‐of‐the‐art models. Moreover, using the critical complexity factors selected in ATCEM, the air traffic complexity could be effectively estimated. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
425.
Enric Massutí Sebasti Monserrat Pere Oliver Joan Moranta Jos Luis Lpez-Jurado Marta Marcos Manuel Hidalgo Beatriz Guijarro Aina Carbonell Pilar Pereda 《Journal of Marine Systems》2008,71(3-4):421
The aim of the present paper is to study the relationships between some climatic indices and parental stock, recruitment and accessibility to trawl fishery of hake (Merluccius merluccius) and red shrimp (Aristeus antennatus) off Balearic Islands (western Mediterranean). Available annual catch per unit effort, recruitment and spawning stock biomass have been used as biological data. As environmental data, the meso-scale IDEA index and the large-scale North Atlantic Oscillation (NAO) and Mediterranean Oscillation (MO) indices have been used. To analyze possible links between these indices with the population dynamics of demersal resources, two non-linear approaches have been applied: (i) stock–recruitment relationships from Ricker and Beverton–Holt models, by sequentially incorporating environment factors; (ii) generalized additive modelling, both classical general and threshold non-additive models were considered. The latter simulate an abrupt change in explicative variables across different phases (time periods or climatic index values). The results have shown that two oceanographic scenarios around the Balearic Islands, associated with macro and meso-scale climate regimes, can influence the population dynamics of hake and red shrimp. This is especially true for recruitment, which seems to be enhanced during low NAO and IDEA indices periods. During these periods, colder-than-normal winters generate high amounts of cold Western Mediterranean Intermediate Waters (WIW) in the Gulf of Lions, which flow southwards and reach the Balearic Islands channels in spring, increasing the productivity in the area. This oceanographic scenario could also be favourable to the distribution of hake on the fishing grounds where the trawl fleet targets this species, increasing its accessibility to the fishery. Both spawning stock and abundance of red shrimp seems to be also enhanced by high MO index periods, which could reflect the increased presence of the saline and warm Levantine Intermediate Waters (LIW) in the study area, extending over the fishing grounds of this species. The proposed interactions can be useful to assess and manage these important demersal resources. 相似文献
426.
我国高速公路安全影响因素分析 总被引:2,自引:0,他引:2
针对我国高速公路交通事故率高及事故严重程度大的现状,结合对我国某早期修建的高速公路安全情况的调查研究,对影响高速公路安全的相关因素进行了分析,并提出了建议。 相似文献
427.
高速公路评价区生态环境影响综合评价初探 总被引:7,自引:0,他引:7
介绍如何确定高速公路生态环境影响评价的因子,界定评价区范围,应用已有的生态综合评价指数法,运用它对高速公路生态影响的实例进行综合评价。 相似文献
428.
为研究复杂艰险铁路隧道的成本控制问题,通过对部分隧道工程成本数据进行分析,总结出铁路复杂艰险隧道〖JP〗工程成本存在亏损情况突出、超长工期工程亏损严重、亏损呈现地区性等突出问题,并从工程技术、工程经济、工程管理、宏观政策等方面分析影响工程成本的主要因素,提出依法合规调整在建工程价款、尽量避免签订无限风险合同等工程成本管理建议。 相似文献
429.
钢拱桥极限承载力的综合三因素检算方法 总被引:6,自引:1,他引:5
通过钢拱桥非线性计算及结果的分析,得出结论,钢拱桥极限承载力的实质是拱肋截面的材料屈服,随着塑性区的扩展,截面刚度降低,从而导致整体非线性位移的急剧增加。运用统计回归,逐一分析横向初始缺陷与横向位移因素指标R1l、拱圈整体横向刚度因素指标R2l和拱桥非保向力因素指标R3l,提出考虑上述三因素的综合因素指标Rl。依此建立钢拱桥极限承载力的综合三因素检算方法。经试验数据的初步验证以及用此方法对4座大跨钢拱桥进行检算的结果表明,该方法综合考虑了横向初始缺陷、横向位移、拱圈整体横向刚度和非保向力等影响钢拱桥极限承载力的主要因素,可简便且准确地检算钢拱桥的极限承载力。 相似文献
430.
以承秦高速公路程家沟隧道工程为背景,分析了影响施工阶段的多个因素,如工程地质条件、自然环境和隧道工程等,以便为风险辨识提供依据。同时指出风险管理是一个动态的过程,应贯穿于施工的全过程,而影响因素分析作为风险管理的一个过程,对隧道工程施工阶段风险辨识起到承上启下的作用。 相似文献