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961.
铁路确报是铁路运输生产的重要内容,是铁路TMIS中重要的信息之一,既有的确报格式存在一些弊端,更改确报格式已成为提高确报信息质量的必须工作.介绍新确报格式内容以及实现流程.  相似文献   
962.
徐泰富  王春民 《船海工程》2012,41(4):115-118
针对船舶液压锚机在检验过程中暴露的质量问题,从齿轮表面质量、齿轮啮合不正常磨损及齿轮啮合噪声等4个方面进行讨论分析,提出相应的解决措施。  相似文献   
963.
One of the main causes of mortality worldwide is air pollution. To tackle this problem, local, regional and national governments have implemented policies to reduce emissions from industrial and on-road sources. However, when these policies are being designed, shipping emissions are often overlooked. There has been a drastic increase in the demand for cruises and its economic relevance is also growing in port-cities. Barcelona is Europe’s leading cruise port, and it is located near the centre of the city. In this context, this paper analyses the impact of cruise ships in the air quality of the entire city of Barcelona using a dataset with information about pollutants and the number of cruises arriving to the port. We show that there is a direct impact between cruises staying at the port and city pollution. Additionally, the size and age of the cruise also affect air quality. The larger (or newer) the cruise is, the higher the emission generated. Moreover, our simulations show that the whole city is affected by these emissions.  相似文献   
964.
新修订的《高速铁路通信工程施工质量验收标准》TB 10755于2018年发布,2019年2月1日正式实施。本文结合工程实际,综合考虑技术进步、管理水平发展、国家相关法律法规以及有关标准的更新等因素,总结设计、施工、监理等单位的经验,从标准修订的背景,新标准整体上的变化,以及各系统的细节变化等方面,对新验收标准进行了详细解读。  相似文献   
965.
Reducing roadside emissions is a common challenge in metropolitan cities. In Hong Kong, conventional liquefied petroleum gas taxis are one of the main contributors to roadside emissions as they operate on the streets 24 h a day with a long daily driving mileage. Moreover, these taxis suffer from a severely poor service reputation. To enhance the environmental friendliness and service quality of the taxi industry, this study explores the market potential of operating premium electric taxis in the dispatching mode. A stated preference survey was conducted to 1410 taxi customers about their taxi-riding choices between premium electric taxis and conventional liquefied petroleum gas taxis. In total, 5640 observations were obtained and used to develop a series of binary logistic regression models with different model formulations for the determination of the significant factors influencing customers’ selections. The findings indicate that walk time to and wait time for taxis were the most critical concerns to the customers, and they were more willing to take premium taxis if their journey distance was longer and their desired improvement on taxi service quality was greater. The socio-demographic status of taxi customers also influences their choices. The associated policy implications are discussed for promoting taxis with better service quality and fewer roadside emissions. The findings provide some policy insights to other international cities that have a similar taxi market to Hong Kong.  相似文献   
966.
As Louisiana continues to experience substantial coastal wetland loss—at the rate of a football field every 45 min—and multiple disasters, state and federal officials struggle with implementing restoration plans in this highly productive ecosystem. The 2007 Louisiana Comprehensive Master Plan for a Sustainable Coast is the first large-scale restoration plan in the United States to incorporate hazard mitigation. However, there is no mandate for local governments to adhere to this plan. Building upon the planning quality and evaluation literature, this study analyzes comprehensive land use plans in Louisiana's coastal zone to systematically assess the quality of the plans within the context of a non-mandated, $50 billion large-scale state restoration plan. Results indicate a great disparity in plan quality; a majority of the local governments lack the capacity to implement the nonstructural programmatic elements of the state's plan. The study concludes with a discussion and recommendations for practice and future research.  相似文献   
967.
针对海外防波堤工程中经常遇到的石料质量不能满足技术规格要求的问题,对国外规范和文献中关于石料质量评估方法的研究成果进行分析。通过将石料质量综合评估法在海外某实际工程中进行应用,并结合设计方案采取施工措施,解决了该工程的石料来源问题。  相似文献   
968.
文章对磁耦合谐振式WPT系统传输特性的影响因素开展了研究与分析,分析了基于SS结构的磁耦合谐振式WPT系统的传输效率模型,基于此模型研究了品质因数对系统传输特性的影响;分别研究了趋肤效应与线圈结构对传输特性的影响,并根据趋肤深度公式分析了多芯情况下的线圈品质因数计算公式,研究结果表明:传输效率与品质因数成正比,且品质因数随着导线芯数的增加而增加;圆柱型螺线管构型具有传输距离远与传输方向性好等优点,更适用于磁耦合谐振式WPT。最后搭建了实验平台,验证了理论分析的正确性。  相似文献   
969.
南昌生米大桥拱肋施工质量控制   总被引:3,自引:0,他引:3  
以南昌生米大桥(主桥为中承式钢管混凝土系杆拱桥)为例,探讨了钢管拱制作及防腐、钢管拱拱肋大型膺架整体吊装架设施工方法、钢管拱拱肋焊接、钢管拱内混凝土配制与现场浇筑、钢管防护涂层施工中需要注意的问题,进而提出大跨钢管混凝土拱桥各施工阶段质量控制要点。  相似文献   
970.
轨道是列车运行的基础,为了保障列车安全、平稳和不间断的运行,轨道必须具有高平顺性.根据轨道不平顺变化特点,利用递推合成BP网络对轨道不平顺状态分周期进行预测,减小了对轨道进行维修作业带来的误差.为了验证模型的有效性,采集了京九线2008年2月~2010年7月的TQI检测数据进行验证,结果表明递推合成BP网络能够在每个TQI变化周期内对轨道的不平顺状态进行较为准确地预测.  相似文献   
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