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51.
智能制造是“中国制造2025”的主攻方向。本文先浅谈了智能船厂,并结合国内首个智能船厂试点对智能船厂的初级发展建设等进行初步探索,主要对船舶智能制造机器人生产线应用进行梳理分析,如工艺流程及布置、生产模式改进、提质增效和人员减配等。 相似文献
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陈勇 《浙江交通职业技术学院学报》2012,13(2):48-52
本文以基于工作过程系统化思想,对汽车车身修复技术课程进行了设计.阐述了本课程基于工作过程系统化的课程设计思路、学习情境设计、课程教学方法及考核方法设计. 相似文献
53.
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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The Floating Production Storage and Offloading Unit (FPSO) is an offshore vessel that produces and stores crude oil prior to tanker transport.Robust prediction of extreme hawser tensions during Floating Production Storage and Offloading (FPSO) operation is an important safety concern. Excessive hawser tension may occur during offloading operations, posing an operational risk. In this paper, AQWA has been used to analyze vessel response due to hydrodynamic wave loads, acting on a specific FPSO vessel under actual sea conditions. Experimental validation of numerical results has been discussed as well.This paper advocates methodology for estimating extreme response statistics, based on simulations (or measurements). The modified ACER (averaged conditional exceedance rate) method is presented in brief detail. Proposed methodology provides an accurate extreme value prediction, utilizing all available data efficiently. In this study the estimated return level values, obtained by ACER method, are compared to the corresponding return level values obtained by Gumbel method. Based on the overall performance of the proposed method, it is concluded that the improved ACER method can provide more robust and accurate prediction of the extreme hawser tension.Data declustering issue has been addressed. Paper highlights ability of ACER method to account for a set of varying sea state probabilities, as required in engineering long term statistical analysis.Described approach may be well used at the vessel design stage, while defining optimal vessel parameters that would minimize potential FPSO hawser tension. 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
58.
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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