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从生产线建立、工艺流程编制、工艺布局设计和生产能力等方面进行分析,提出了轨道交通车辆工艺流程标准化设计方法和优化方法。基于精益管理理念和工序能力测算法,可以合理编制标准化工艺流程,从而降低劳动强度,提高生产效率。 相似文献
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通过对散粮输送行业中常见的工艺设备进行探究,分析设备运行过程中可能存在的问题,提出合理的解决方案,为散粮系统工艺设计及工程运行提供重要参考意义。 相似文献
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Hristos Karahalios 《Maritime Policy and Management》2017,44(4):426-441
Regulations are introduced by the International Maritime Organization (IMO) into the maritime industry as the result of safety accidents and/or pollution incidents. When there is lack of historical data, then the IMO appoints experts in order to collect information regarding the costs and benefits generated to a stakeholder of the maritime industry once implementing a maritime regulation. Therefore, the role of experts in providing qualitative and quantitative information is crucial with respect to the quality of the maritime regulatory process within the IMO or other regulatory authorities. In this article, a methodology is proposed involving common criteria in determining the expertise of an individual in the maritime regulatory field. As essential part of the research methodology, analytic hierarchy process (AHP) is utilized to determine the expertise of an individual based on his/her own judgements. The regulatory authorities and other stakeholders of the maritime industry may use this method when selecting experts for decision-making. In this article, a simulation is carried showing the potentials of the AHP methodology in expertise evaluation followed by a case study. 相似文献
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Building safe and effective roundabouts requires optimizing traffic (operational) efficiency (TE) and traffic safety (TS) while taking into account geometric factors, traffic characteristics and local constraints. Most existing simulation-based optimization models do not simultaneously optimize all these factors. To capture the relationship among geometry, efficiency and safety, we put forward a model formulation in this paper. We present a new multi-criteria and simultaneous multi-objective optimization (MOO) model approach to optimize geometry, TE and TS of urban unsignalized single-lane roundabouts. To the best of our knowledge, this is the first model that uses the multi-criteria decision-making method known as analytic hierarchy process to evaluate and rank traffic parameters and geometric elements of urban single-lane roundabouts. The model was built based on comprehensive review of the research literature and existing roundabout simulation software, a field survey of 61 civil and traffic expert engineers in Croatia, and field studies of roundabouts in the Croatian capital city of Zagreb. We started from the basis of Kimber’s capacity model, HCM2010 serviceability model, and Maycock and Hall's accident prediction model, which we extended by adding sensitivity analysis and powerful MOO procedures of the bounded objective function method and interactive optimization. Preliminary validation of the model was achieved by identifying the optimal and most robust of three geometric alternatives (V.1-V.3) for an unsignalized single-lane roundabout in Zagreb, Croatia. The geometric parameters in variant V.1 had significantly higher values than in the existing design V.0, while approaches 1 and 3 in variant V.2 were enlarged as much as possible within allowed spatial limits and Croatian guidelines, reflecting their higher traffic demand. Sensitivity analysis indicated that variant V.2 showed the overall highest TE and TS across the entire range of traffic flow demand and pedestrian crossing flow demand at approaches. At the same time, the number of predicted traffic accidents was similar for all three variants, although it was lowest overall for V.2. The similarity in predicted accident frequency for the three variants suggests that V.2 provides the greatest safety within the predefined constraints and parameter ranges explored in our study. These preliminary results suggest that the proposed model can optimize geometry, TE and TS of urban single-lane roundabouts. 相似文献
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在2004年的国家助学贷款新政策背景下,尽管出现了许多利好方面,仍存在一些尚未解决的问题。而完整的国家助学贷款市场应当是由一级市场和二级市场组成的一个有序开放式的市场体系:一级市场是创造国家助学贷款形成借贷关系的市场,二级市场是创造国家助学贷款债权转让的市场。资产证券化是我国目前解决问题、完善市场、金融创新的重要选择,这项选择不仅很有必要,且基本具备了可行条件。当然,我国如果进行国家助学贷款资产证券化,还需要建立良好的征信制度和其它保障制度。 相似文献
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唐山港曹妃甸港区作为一个新兴港区,港口建设造陆工程对港区潮流、泥沙运动均产生影响,需要谨慎应对,以确保工程建设不对港区潮流和泥沙淤积造成不利影响。本文通过研究华能唐山港曹妃甸港区煤码头工程造陆宽度增加对港区潮流、泥沙运动产生的影响,加宽了堆场造陆宽度,优化了总体工艺设计方案。 相似文献