A comparative study on damage assessment of tubular members subjected to mass impact

This paper focuses on the behaviour of tubular members when subjected to low-velocity mass impact. Particular emphasis is given to the numerical assessment of impact damage and the classification of impact response of tubular members. Damage extents of 12 tubular frame test models were predicted and used for quantifying the modelling uncertainties of the numerical tools. USFOS and ABAQUS software packages were used with beam and shell elements, respectively. Based on the test results and the parametric studies performed, the influence of the geometrical parameters and the interaction between the local shell denting and the global beam deformation modes are discussed. A classification of the impact response of the tubular members based on their relative resistance against shell denting and beam plastic collapse load is proposed. Finally, existing analytical models for each energy dissipation mode are visited and modifications are proposed.     

饱和软粘土地基沉降速率的计算方法

为了探讨饱和软粘土地基沉降速率的计算方法,根据饱和软粘土应变固结度与应力固结度的近似关系,推导出地基沉降速率的计算公式,提出了饱和软粘土地基沉降速率的计算方法,所得结果与工程实测数值相符。结果表明:软土层超固结比对计算结果有较大影响,计算时应根据地质资料及地区经验合理选择各土层超固结比。     

Reintroducing attitude theory in travel behavior research: The validity of an interactive interview procedure to predict car use

A methodological challenge is to develop methods which satisfy the need in transport planning of accurately forecasting travel behavior. Drawing on a review of the current state of attitude theory, it is argued that successfully forecasting travel behavior relies on a distinction between planned, habitual, and impulsive travel. Empirical illustrations are provided in the form of stated-response data from two experiments investigating the validity of an interactive interview procedure to predict household car use for different types of trips, either before or after participants were required to reduce use.     

对GPS接收机欺骗式干扰效果的灰色评估模型和算法

对GPS接收机的欺骗式干扰效果评估是一个全新而又十分复杂的问题,而且由于存在信息不完全和不确定等因素,故灰色系统理论是解决此类评估问题的一种很好的办法。通过分析对GPS接收机的欺骗式干扰方法,提出了对欺骗式干扰效果的灰色评估方法,建立了评估模型和评估算法。并利用MATLAB语言进行了仿真评估举例,结果表明该方法简单有效,可对GPS接收机的欺骗式干扰效果进行科学、合理的评估。     

企业降低财务费用的策略探讨

企业的财务人员可以在实际工作中采取灵活的方法,合理降低企业的财务费用,从而有效降低生产经营成本,提高企业竞争力。     

用自动子结构有限元法实现预应力混凝土桥空间应力分析

本文介绍了一种用于求解大型有限元问题的方法－自动子结构方法。用该方法对某地一座三跨预应力混凝土连续梁进行了桥跨中支点墩顶梁段混凝土应力分析，取得良好效果。     

内河架空直立式集装箱码头结构计算中的作用效应组合探讨

文章中采用单位力法对内河大水位差架空直立式集装箱码头可能出现的荷载工况进行了有限元计算，并采用MATLAB软件编程对计算结果进行分析组合，得到了计算结构各主要构件控制内力的最不利作用效应组合情况，提出了内河架空直立式集装箱码头结构计算的作用效应组合方法。     

Optimal tyre usage for a Formula One car

Variations in track temperature, surface conditions and layout have led tyre manufacturers to produce a range of rubber compounds for race events. Each compound has unique friction and durability characteristics. Efficient tyre management over a full race distance is a crucial component of a competitive race strategy. A minimum lap time optimal control calculation and a thermodynamic tyre wear model are used to establish optimal tyre warming and tyre usage strategies. Lap time sensitivities demonstrate that relatively small changes in control strategy can lead to significant reductions in the associated wear metrics. The illustrated methodology shows how vehicle setup parameters can be optimised for minimum tyre usage.     

关于轮机工程专业船舶电气教学的几点思考

《船舶电气设备与系统》是轮机管理专业学生的一门主修专业课程,它对培养学生扎实的理论基础、较强的动手能力及顺利通过大证考试起着重要的作用。文章针对非船电专业船舶电气的教学进行了探索和研究。     

考虑结构长期性能多梁式预应力混凝土斜梁桥合理施工方法研究

采用梁格法建立多梁式预应力混凝土斜梁桥空间有限元分析模型,通过模拟不同施工过程进行计算分析,发现采用不同施工方法实现的结构成桥后的内力和变形差异很大;支座反力的分布也有较大的差别.成桥后钢束二次效应对结构的内力和反力的影响也较大,因此在设计选择斜粱桥施工方法时应引起注意.