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31.
张兴容 《铁道劳动安全卫生与环保》1993,(4):293-296
群众性的自主管理活动是宝钢安全管理的基础。本文介绍了宝钢自主管理活动的特点,具体步骤和基本内容,以及它们开展这个活动所取得的成果。实践证明,自主管理作为一种现代化的管理方式和PDCA循环中的一项重要活动在企业的安全生产中能取得较好的效果。 相似文献
32.
根据高速铁路牵引负荷过程测试数据,构建基于热传递微分方程的牵引变压器温升模型,并给出牵引变压器中可靠性最弱的热改性绝缘纸的相对老化率算式,据此计算牵引变压器的寿命损失.结果表明:为了有效利用牵引变压器寿命损失,可以降低牵引变压器的容量,该高速铁路选择2×31.5 MVA容量等级的牵引变压器较为合理;但是,为了充分利用既有单相牵引变压器和相关设施,针对当前的运输组织条件提出一主三备的牵引变压器配置优化方案,该方案能够有效提高牵引变压器容量利用率,对电能质量的影响远低于GB/T15543-2008标准的限值要求,具有良好的技术经济性. 相似文献
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To solve the problem of life estimation of reinforced concrete (RC) members after fire, an analysis is made of the resistance of RC members after fire. On basis of the resistance, the life of RC members after fire is analyzed by using JC (Jukes and Cantor) method. Then the calculation models for the resistance and the life estimation of RC members after fire are put forward, and an example analysis proves their reliability and accuracy. 相似文献
35.
Extensive published literature shows that hydrated lime improves Hot Mix Asphalt (HMA) durability. Its impact on the environmental impact of HMA has not been investigated. This paper presents a comparative Life Cycle Assessment (LCA) for the use of HMA without hydrated lime (classical HMA) and with hydrated lime (modified HMA) for the lifetime of a highway. System boundaries cover the life cycle from cradle-to-grave, meaning extraction of raw materials to end of life of the road. The main assumptions were: 1. Lifetime of the road 50 years; 2. Classical HMA with a life span of 10 years, maintenance operations every 10 years; 3. Modified HMA with an increase in the life span by 25%, maintenance operations every 12.5 years. For the lifetime of the road, modified HMA has the lowest environmental footprint compared to classical HMA with the following benefits: 43% less primary total energy consumption resulting in 23% lower emissions of greenhouse gases. Partial LCAs focusing only on the construction and/or maintenance phase should be used with caution since they could lead to wrong decisions if the durability and the maintenance scenarios differ. Sustainable construction technologies should not only consider environmental impact as quantified by LCA, but also economic and social impacts as well. Avoiding maintenance steps means less road works, fewer traffic jams and hence less CO2 emissions. 相似文献
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This paper develops a systematic and practical construction methodology of a representative urban driving cycle for electric vehicles, taking Xi’an as a case study. The methodology tackles four major tasks: test route selection, vehicle operation data collection, data processing, and driving cycle construction. A qualitative and quantitative comprehensive analysis method is proposed based on a sampling survey and an analytic hierarchy process to design test routes. A hybrid method using a chase car and on-board measurement techniques is employed to collect data. For data processing, the principal component analysis algorithm is used to reduce the dimensions of motion characteristic parameters, and the K-means and support vector machine hybrid algorithm is used to classify the driving segments. The proposed driving cycle construction method is based on the Markov and Monte Carlo simulation method. In this study, relative error, performance value, and speed-acceleration probability distribution are used as decision criteria for selecting the most representative driving cycle. Finally, characteristic parameters, driving range, and energy consumption are compared under different driving cycles. 相似文献
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How and why travel contributes to our life satisfaction is of considerable import for transportation policy and planning. This paper empirically examines this relationship using data from the American Time Use Survey. It finds that, controlling for relevant demographic, geographic, and temporal covariates, travel time per day is significantly and positively associated with life satisfaction. This relationship is attenuated, but still significant, when the amount of time spent participating in out-of-home activities is controlled for. Time spent bicycling is strongly associated with higher life satisfaction, though it attains significance only in some models; time spent walking is also quite positive, though it is not significant. However, both walking and bicycling are positively and significantly associated with life satisfaction when time spent on purely recreational walking and bicycling is included. Life satisfaction is positively and significantly associated with time spent traveling for the purposes of eating and drinking, religious activities, volunteering, and playing and watching sports. Travel time exhibits a strong positive relationship with life satisfaction in smaller towns and cities, but in large cities the association weakens, and for very large cities travel time may actually not be associated with life satisfaction at all. This may be due to the costs of traffic congestion, which disproportionately exists in large cities. In all, while the associations between travel and life satisfaction are clear, the causal story is complex, with the positive relationships potentially being explained by (1) travel allowing us to access destinations that make us happy, (2) the act of travel itself being fulfilling, and/or (3) intrinsically happier people being more likely to travel. In all likelihood, all three factors are at play. 相似文献
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疲劳耐久性是直接影响摩托车行驶安全的重要性能,摩托车生产企业非常有必要针对每款新车开展疲劳耐久性试验。以某款摩托车为例,进行路谱采集和疲劳耐久试验,采集车架上某关键部位的应变监测信号,探索采用S-N曲线和Miner线性累积损伤理论对车架寿命进行预测。通过试验表明,台架耐久试验相比道路耐久试验更高效、更安全,为摩托车的疲劳耐久试验和车架的优化设计提供了参考依据。 相似文献
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