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371.
陈静 《武汉船舶职业技术学院学报》2011,(5):79-80,87
语言是文化的载体,思维的载体,中西方不同的思维模式决定了中西方语言应用中形态的差异性。本文对汉语和英语思维特征进行了描述和比较,目的是为了让语言学习者更好地了解语言背后的文化内涵,并能依照不同民族的思维特点,组织合适的语言。 相似文献
372.
为了进一步节能减排,建设绿色港口,连云港在吸取国内外岸电技术成功技术的基础上,开拓了自己的岸电技术。介绍了连云港港岸电技术的由来,其在绿色水运中的意义,技术方案及其优点。阐述了实施该方案需要解决的问题。对中国在岸电方面引领世界的前景进行了展望。 相似文献
373.
Short-term forecasting of high-speed rail (HSR) passenger flow provides daily ridership estimates that account for day-to-day demand variations in the near future (e.g., next week, next month). It is one of the most critical tasks in high-speed passenger rail planning, operational decision-making and dynamic operation adjustment. An accurate short-term HSR demand prediction provides a basis for effective rail revenue management. In this paper, a hybrid short-term demand forecasting approach is developed by combining the ensemble empirical mode decomposition (EEMD) and grey support vector machine (GSVM) models. There are three steps in this hybrid forecasting approach: (i) decompose short-term passenger flow data with noises into a number of intrinsic mode functions (IMFs) and a trend term; (ii) predict each IMF using GSVM calibrated by the particle swarm optimization (PSO); (iii) reconstruct the refined IMF components to produce the final predicted daily HSR passenger flow, where the PSO is also applied to achieve the optimal refactoring combination. This innovative hybrid approach is demonstrated with three typical origin–destination pairs along the Wuhan-Guangzhou HSR in China. Mean absolute percentage errors of the EEMD-GSVM predictions using testing sets are 6.7%, 5.1% and 6.5%, respectively, which are much lower than those of two existing forecasting approaches (support vector machine and autoregressive integrated moving average). Application results indicate that the proposed hybrid forecasting approach performs well in terms of prediction accuracy and is especially suitable for short-term HSR passenger flow forecasting. 相似文献
374.
提出船舶船舶主机机旁自动化系统设计中几个常见的问题,并对进行剖析,提出改进措施,供设计、生产及检验单位参考,避免类似问题的重复发生。 相似文献
375.
Green turtles (Chelonia mydas) are among the most high profile species in San Diego Bay, California, and understanding impacts of coastal development and industry is essential to the management and conservation of this local population. Here we describe power plant changing energy production and its impact on turtle habitat use and our ability to research and manage this population. For over 20 years, green sea turtles have been captured, assessed, and tagged near the South Bay Power Plant (SBPP) in the San Diego Bay; from 2002–2011, 104 turtles were captured on 212 occasions. As the 50-year-old SBPP generates less energy, effluent patterns change and water temperatures decrease, presumably to more natural conditions. There has been a concurrent decrease in turtle-capture success, perhaps due to lesser visitation to the effluent site where nets are tended. Seasonal catch-per-unit-effort declined from a high of 4.14 turtles per monitoring day, to a nine-year low of 1.33 during the 2010–2011 season. It is already apparent that management decisions related to energy policy are affecting the habitat and behavior of this stock of endangered turtles. Green turtles are expected to remain in the San Diego Bay after the SBPP becomes inoperative and continuing research will monitor future impacts and distribution shifts resulting from the expected changes in thermal pattern within south San Diego Bay. Research efforts to study this population (i.e., capture methods and locations) will require modification in response to these changes. Lessons learned here are applicable to the immediate coastal development of San Diego, as well as at similar interactions between marine turtles and industrial thermal effluent discharge throughout Southern California, the United States, and beyond. 相似文献
376.
金碧筠 《城市轨道交通研究》2014,17(12)
作为在紧急情况下为轨道交通列车辅助系统供电的应急电源,铅酸或镍铬电池被普遍使用;随着技术的不断发展,锂离子电池的应用也越来越广泛.介绍了GJCL-A型锂离子轨道交通车载智能应急电源系统的组成、工作原理、设计方案及试点应用情况.GJCL-A型锂离子轨道交通车载智能应急电源系统的试验应用结果表明,用于车厢的110V应急供电4 300 s后,其剩余电量仍有40%以上. 相似文献
377.
378.
分析了并联逆变型晶闸管中频电源产生换相失败的原因,提出老换相失败保护新措施,经过实验和实践结果表明,新措施对各种原因产生的换相失败均有保护作用,且简单实用、效果良好。 相似文献
379.
针对公路隧道供配电系统设计中存在的一些问题,结合实际工程中供配电系统的设计、施工及运营管理经验进行简要分析,并就公路隧道供配电系统的设计提出具体意见和建议,供设计、施工人员参考 相似文献
380.