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排序方式: 共有1920条查询结果,搜索用时 390 毫秒
641.
监事会是随着市场经济的发展而产生出来的,在公司治理结构中占有重要地位,我国从引入监事会到发展到现在虽然取得了一定成就但是仍然存在诸多不足,对于作为我国国民经济主体的国有企业,在这方面又有自己独到的特点,如何对监事会进行改进以便能真正实现其监督职能成为整个社会所关注的问题。 相似文献
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643.
佘丹 《电力机车与城轨车辆》2002,25(2):30-32
通过对电力机车装配作业中螺纹紧固件松动问题的分析,找出其产生的原因,并提出了防止螺纹紧固件松动的措施。 相似文献
644.
Raquel Espino Juan de Dios Ortúzar Concepcin Romn 《Transportation Research Part A: Policy and Practice》2007,41(10):899-912
We analyse the choice of mode in suburban corridors using nested logit specifications with revealed and stated preference data. The latter were obtained from a choice experiment between car and bus, which allowed for interactions among the main policy variables: travel cost, travel time and frequency. The experiment also included parking cost and comfort attributes. The attribute levels in the experiment were adapted to travellers’ experience using their revealed preference information. Different model specifications were tested accounting for the presence of income effect, systematic taste variation, and incorporating the effect of latent variables. We also derived willingness-to-pay measures, such as the subjective value of time, that vary among individuals as well as elasticity values. Finally, we analysed the demand response to various policy scenarios that favour public transport use by considering improvements in level-of-service, fare reductions and/or increases in parking costs. In general, demand was shown to be more sensitive to policies that penalise the private car than those improving public transport. 相似文献
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646.
DF4B、DF4D机车空压机润滑油惯性乳化原因和解决措施 总被引:1,自引:0,他引:1
压缩机吸风口位于冷却主风道附近,使得潮湿空气被直接吸入机内,并冷凝成水,这是DF4B、DF4DN种机型压缩机润滑油惯性乳化的重要原因。本文从调研、检测和试验方面分析乳化原因,并提出采用提高抗乳化性能的200号压缩机润滑油等解决措施。 相似文献
647.
通过简要分析土工击实试验中超尺寸颗粒对最大干密度值的影响,提出实际应用中超尺寸颗粒常见的处理方法.有助于验证“公路土工试验规程”中超尺寸颗粒处理推荐修正公式的科学性和合理性。 相似文献
648.
《1972年国际海上避碰规则》中的“驾驶和航行规则”和STCW 78/95公约中的“航行值班中应遵循的原则”都把了望条款列为首要条款,对这一条款的深入理解和研究,无疑是十分必要的,在简短介绍了这一条款的内容、重要性后,着重分析一个事故发生的原因,并提出了一些预防对策,以提高了望水平,确保海上航行安全。 相似文献
649.
樊海港 《铁路通信信号工程技术》2005,(6):37-39
详细阐述了38号道岔的安装和调试方法;图表详释S700K电动转辙机的动作过程及故障处理。 相似文献
650.
Richard A. Jahnke 《Journal of Marine Systems》1998,14(3-4)
The response of pore water oxygen, nitrate, sulfate, sulfide, ammonium and methane and particulate organic carbon distributions to the input of 8.5 million m3 (3.8×1012 g) of organic-rich waste materials is simulated. The deposit is assumed to be conical with a maximum thickness of approximately 20 m. Remineralization reactions within the deposit rapidly deplete any initially available pore water oxidants such as oxygen, nitrate and sulfate, and are subsequently dominated by fermentation reactions. Diffusion downward of reduced metabolites, sulfide, ammonium and methane, depletes the available oxidants in the pore waters below the waste pile, increasing the thickness of the anoxic layer. While the impacted region is limited to essentially the deposition site, recovery of the pore waters is estimated to be >104 years. The overall computational results are corroborated by the pore water distributions observed at turbidite boundaries. Numerous uncertainties in the parameterizations limit the overall accuracy of the calculations presented. The most significant of these are: (1) A quantitatively accurate assessment of the remineralization rate of the deposited organic matter including its rate of inoculation by abyssal microorganisms; (2) a detailed assessment of potential non-diffusive pore water transport processes including advection due to compaction and buoyancy-driven flows and enhanced exchange due to macrobenthic irrigation activities and (3) an assessment of the potential alteration of pore space and methane reactivity due to gas hydrate formation. 相似文献