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141.
稳定分析是斜拉桥设计的重要组成部分。珠江桥稳定分析按特征值屈曲问题处理,采用整体有限元分析模型,分析了施工、运营4个工况。计算结果表明珠江桥主桥在施工及运营阶段均不会发生整体失稳。 相似文献
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文章分析了现阶段广西船舶生产企业现状及存在的主要问题,并从管理角度提出了推动船舶修造工业健康发展的对策和建议,为广西船舶生产企业提升船舶生产水平、实现跨越式发展提供思路。 相似文献
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文章通过分析当前高速公路路面施工安全状况,划分高速公路路面施工危险区域,找出存在的危险控制点,确定项目重大危险源。同时针对项目施工主要危险区域及危险控制点,提出了高速公路路面现场施工安全管理方法。 相似文献
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为解决船舶产品设计(Ship Product Design, SPD)软件在舾装件制作图出图及物料清单(Bill of Material, BOM)输出方面经常需要设计师大量手动干预、设计效率低下的问题,开发舾装快速出图系统。基于SPD二次开发接口,实现舾装标准件数量和材料的快速抽取,1∶1制作图的批量生成,材料明细表和部件列表的自由增删改,图名、图号和页码的自动批处理,各类BOM数据定制化表格的自动输出等功能。该系统成功应用于实船舾装设计,大幅提升舾装件制作图和BOM表的绘制效率,为后续舾装件的自动化和智能化生产提供数据支撑。 相似文献
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Jeom Kee Paik Jae Myung Lee Young II Park Joon Sung Hwang Chang Wook Kim 《Marine Structures》2003,16(8):567-600
Many bulk carrier losses have been reported of late, and one of the possible causes of such casualties is thought to be the structural failure of aging hulls in rough weather. In aging ships, corrosion and fatigue cracks are the two most important factors affecting structural safety and integrity. This paper uses a set of the time-dependent corrosion wastage models for 23 different member locations/categories of bulk carriers previously developed by the authors, based on the available corrosion measurements for existing large bulk carrier structures. Differences due to the location and corrosion severity of every member type are taken into account. The nominal design corrosion values for the primary members are suggested based on the annualized corrosion rates obtained in the present study. The effect of time-variant corrosion wastage on the ultimate hull girder strength as well as the section moduli is studied. The criteria for repair and maintenance of heavily corroded structural members so as to keep the ultimate longitudinal strength at an acceptable level are discussed. Important insights and conclusions developed are summarized. 相似文献
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Road traffic accident fatalities lead to important private and social costs in the metropolitan areas of most low and middle income countries. An important share of these fatalities is due to injuries to the head and the neck. Helmets can provide efficient protection, but many drivers do not use them. We focus on helmet use behavior among motorbike users in Delhi. We use a detailed data set collected for the purpose of the study. To guide our empirical analysis, we rely on a model in which drivers decide on self-protection and self-insurance. The empirical findings suggest that risk-averse drivers are more likely to wear a helmet and that this has no systematic effect on speed. Helmet use also increases with education. Drivers who show a higher awareness of road risks seem to be both more likely to wear a helmet and to speed less. Controlling for risk awareness, we observe that drivers tend to compensate between speed and helmet use. The results can provide a basis for awareness-raising policies. They also show that improvements to the road infrastructure risk leading to risk-compensating behavior. 相似文献