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1.
驾驶员安全可靠性多因素分析   总被引:10,自引:1,他引:10  
影响驾驶员安全可靠性的身心因素很多,研究中对22项指标进行分析,将有关指标合并,归纳为6种主因子:第一主因子相关变量5种,反映驾驶员的反应能力;第二主因子相关变量4种,反映中枢神经系统的平衡控制能力;第三主因子相关变量5种,反映驾驶员视觉功能;第四主因子相关变量4种,反映注意综合品质;第五主因子相关变量3种,反映驾驶员速度判断能力;第六主因子为驾驶员听觉能力。基于主因子分析进一步整合,建立驾驶员安全可靠性评价指标体系。  相似文献   
2.
Developments in UK shipping: the tonnage tax   总被引:1,自引:0,他引:1  
The new UK Government, elected in May 1997, came to power with a commitment to reverse the decline of the UK shipping industry and enhance the employment prospects of UK seafarers. The Government commissioned Lord Alexander of Weedon to investigate the case for a tonnage tax. In this paper, the economic arguments for supporting the UK shipping industry are reviewed. There is some evidence that the UK holds a comparative advantage in world markets in key sectors of the shipping industry and on-shore maritime related activities, but is being undermined by lower foreign taxes. In the absence of government support, the UK shipping industry is likely to continue to decline, and, by further reducing the supply of qualified UK ex-seafarers, put at risk the successful on-shore activities. Various measures that might be used to support a national shipping industry, e.g. a tonnage tax, are considered. The paper concludes by discussing the likely impact of the tonnage tax on the UK's shipping industry.  相似文献   
3.
This paper presents a review and classification of traffic assignment models for strategic transport planning purposes by using concepts analogous to genetics in biology. Traffic assignment models share the same theoretical framework (DNA), but differ in capability (genes). We argue that all traffic assignment models can be described by three genes. The first gene determines the spatial capability (unrestricted, capacity restrained, capacity constrained, and capacity and storage constrained) described by four spatial assumptions (shape of the fundamental diagram, capacity constraints, storage constraints, and turn flow restrictions). The second gene determines the temporal capability (static, semi-dynamic, and dynamic) described by three temporal assumptions (wave speeds, vehicle propagation speeds, and residual traffic transfer). The third gene determines the behavioural capability (all-or-nothing, one shot, and equilibrium) described by two behavioural assumptions (decision-making and travel time consideration). This classification provides a deeper understanding of the often implicit assumptions made in traffic assignment models described in the literature. It further allows for comparing different models in terms of functionality, and paves the way for developing novel traffic assignment models.  相似文献   
4.
应用了电子学最新发展成果的新型柴油发动机和柴油燃料将会颠覆你以前对柴油车的所有偏见。不仅如此,它还将为汽车维修行业提供新的赢利机会。  相似文献   
5.
<正>本文译自美国MOTOR杂志。当我们期待着实用化的车用动力装置取代传统的汽油内燃机之时,汽车工程师们也仍在继续努力探索提高传统汽车发动机性能的方法。菲亚特公司的多气门电子控制系统算得上是最新成果的实例。  相似文献   
6.
我认为,造船师和轮机师考虑海上环境设计的船舶,它们99.9%的时间在海上渡过。但他们忘了,这些船舶还必须进入河道装卸货物。当某件引起公众高度关注的事故发生,船舶建造者或许会进入公众视线,发现他们犯有疏忽罪,要为建造了动力不足和操纵不良的船舶负责。一位引航员的观点国际  相似文献   
7.
检修站这一概念起源于赛车行业,并得到了高度发展。而如今它获得了车辆生产和检修商西门子公司的青睐,并在英格兰南部专门建造的列车检修段得到了应用。  相似文献   
8.
“Today, the idea of allowing aircraft pilots to operate as they see fit, without any control from the land, is unthinkable. Will the same things apply to ships in twenty to thirty years’ time?”Current maritime pilotage regimes are clearly seen in some quarters as too restrictive and old fashioned. Change is “in the air” and VTS, pilotage, and the relationship between them cannot be immune to it. Subject to the attainment of the appropriate standards by both ships and their crews there is no practical reason why more flexible Vessel Traffic Management cannot be introduced. The required technology is largely available and, with the introduction of AIS, the required dynamic data can be available. Technical problems foreseen are believed capable of solution. The more significant obstacles to implementation are, therefore, largely political, commercial, organisational, and cultural. These issues are discussed in this paper taking into account the viewpoints of major stakeholders.  相似文献   
9.
Fe—Mo合金的时效析出行为   总被引:1,自引:0,他引:1  
用 X 射线、电子衍射及透射电镜观察等方法研究了 Fe-27Mo 及 Fe-16Mo 合金的时效析出行为.结果发现,在873~1453K 时效时.时效初期,两种合金中均有一种新的过渡相——R 相析出.随时效进行,过渡相 R 将向平衡相μ(1213~1453K)或 Laves(873~1213K)转度.过渡相 R 为菱形点阵,点阵常数α=0.8977nm,α=74.4°,其 Mo 含量为48%,呈棒状或块状形态析出.时效初期由于过渡相 R 的析出引起合金硬化.  相似文献   
10.
A hypothesis of the minimum energy of secondary flow, suggested by Bessho, is introduced here. According to this hypothesis, it can be expected that hull forms having frame lines with a minimum energy of secondary flow show less form drag. In the first part of this article, secondary flow energy is evaluated for the cases with and without a free-surface effect, and Bessho’s hypothesis is confirmed for practical hull forms. Then optimization methods for the stern hull form are suggested, in which a nonlinear optimization technique is introduced. Numerical examples are given for a practical tanker hull form and a practical container hull form. From these studies, the suggested optimization method can be confirmed as a simplified and practical design method to the select frame lines of stern hull forms.  相似文献   
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