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用因素分析理论分析铁路运营指标 对铁路货运收入的影响 总被引:1,自引:0,他引:1
论文分析了货物周转量、发送量、装车数、平均运程及货车静载重等铁路运营指标与铁 路货运收入的关系,运用微积分方法推导出了指标因素影响分析的计算公式,得出了分析铁路 运营指标对铁路货运收入影响的计算方法,并给出了计算实例. 相似文献
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试运行是城市轨道交通开通试运营前的一个必要环节.对试运行的概念、内容进行详细讨论分析,提出试运行的主要考核指标:运行图兑现率、正点率、掉线率、设备故障率、ATP正确率等,以反映系统的服务水平、可靠性和安全性.为保证较高的开通水平和服务水平,试运行合格时运行图兑现率和正点率应达到90%以上. 相似文献
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为保证既有北京地铁13号线东直门车站的正常运营和既有地下结构的安全,需严格控制机场线东直门站明挖基坑施工引起的水平及竖向地层位移.预测机场线东直门站明挖基坑施工引起的既有车站结构的沉降曲线、评估明挖基坑施工引起的既有车站沉降变形对其现状结构的影响,同时根据行车安全的要求,综合各种影响因素,提出明挖基坑施工时对既有车站结构的沉降控制指标.为采取合理的施工辅助措施,建立有限元模型,计算和分析明挖基坑在紧邻既有车站情况下既有车站结构的受力特征,并评价结构的安全性. 相似文献
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介绍扁铲侧胀试验的试验原理、资料整理以及参数计算方法,并初步与土工试验结果进行对比,结合扁铲侧胀试验在地铁勘察实际工程中的应用,说明该试验在黄土地区有较广阔的推广前景。 相似文献
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Manuel Hidalgo Enric Massutí Joan Moranta Joan Cartes Josep Lloret Pere Oliver Beatriz Morales-Nin 《Journal of Marine Systems》2008,71(3-4):367
This study evaluates the link between the recruitment process of European hake (Merluccius merluccius L.) of the Balearic Islands (western Mediterranean) and the environmental and physiological conditions. Spatio-temporal variation of abundance and condition of fish were evaluated at two locations each with different oceanographic conditions, one in the north (Sóller, SO) and another in the south (Cabrera, CA) of Mallorca Island. Environmental variables explored were hydrography, sediment characteristics, phytoplankton pigment concentration (ppc) and the trophic resources of hake. Individuals were divided in three life stages: recruits, post-recruits and young adults. Hepatosomatic index (HSI), relative condition index (Kn), gonadosomatic index (GSI) and fullness index (FI) were analysed for the three life stages. Recruitment starts in February with the incorporation of smaller hakes, and it can be followed through spring and early summer with a peak in April. However, some spatial heterogeneity in the recruitment process has been found between north and south of the Island. The main pulse of recruitment occurred at a different time in the two areas. Spatial heterogeneity was also consistent with the condition of hake recruits, with higher values of Kn and HSI at SO than at CA. Maximum values of Kn were found in February at SO and in April at CA, coinciding with the start of the different recruitment pulses to the fishing grounds. Post-recruits and young adults also showed higher condition at SO than at CA. The arrival in spring of the Western Winter Intermediate Waters (WIW) drives the spatial-temporal variation in abundance and condition of hake. Ppc was highly correlated with recruit abundance with a time lag of two months, while for post-recruits the time lag was three months. The observed differences in the condition of hake between areas could be a consequence of the fact that the waters to the north of Mallorca are comparatively more under the seasonal influence of WIW which is formed in more productive areas. Thus, this study characterises the short temporal and spatial variability in the hake recruitment process off the Balearic Islands, both in terms of abundance and fish condition. This pattern is explained on the basis of the mesoscale environmental variability observed between north and south of Mallorca and the ecological adaptive strategy of recruiting in the optimal environmental season. 相似文献
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