从站务英语教学看高职专门用途英语课程建设与教学研究

高职专门用途英语是符合当下国内外发展而诞生的一门较为新颖的学科,它在应用时拥有很强的定向性和实践性,但同时在教师的教学中和学生的学习中拥有明显的跨学科性。因此这就在准备课程和建设课程方面向教师提出了更高的要求,对专门用途英语课程建设的研究有着重要的意义。教师对于专门用途英语课程的教学研究尚处于初级阶段,专门用途英语课程由于是一个比较宽广的范畴,因此本文以其中的站务英语课程为例进行研究。     

公路隧道交通智能无线预警系统布设方案

随着我省长隧道及隧道群的不断增多,隧道安全管理和隧道事故的预防已成为重要的研究课题。文章在分析隧道事故预防现状的基础上,从研究隧道事故预警、事故应急体系和隧道事故发生机理入手,根据当前隧道事故预警和应急处理存在的问题,提出建立有效的隧道事故智能预警系统的方案,以提高隧道预警和事故应急处理的能力和效率。     

Serial cost allocation in the cooperative purchasing organization

Under the seller＇s quantity discount, buyers self-organize or rely on a third party to aggregate their purchasing quantities to obtain lower prices. Because of the unequal member contributions in the cooperative purchasing organization, the buyers＇ strategy is different, the members often fluctuate, and the organizations do not sustain themselves. An effective mechanism is necessary to improve the performance of purchasing groups. We study the various forms of cost allocation mechanism in practice. Different allocation rules may have influence on the buyers＇ behavior （i.e., purchasing quantities, whether joining the organization or not）. We analyze the serial cost allocation and equilibrium purchasing quantity based on a Nash equilibrium, and the results show that each buyer is worse off when not participating in the existence buying organization of the other buyers. We further find that the serial mechanism just confirms the most efficient Nash equilibrium： reasonable cost allocation rule is necessary for the subjects to identify their optimal strategy.     

钢箱拱临时合拢构造措施及力学行为分析

钢箱一砼组合拱桥采用两段钢箱吊装合拢施工,在拱脚、拱顶利用连接板临时合拢整个钢箱拱肋,合拢连接板的力学行为对拱肋受力、安全显得十分必要,通过对钢箱拱肋临时合拢连接板的参数计算,得出钢箱拱两段合拢中拱脚、拱顶处连接板的合理布置理论依据,并建立有限元分析合拢过程中钢箱拱肋的受力行为,获得典型作用下的连接板布置数量。     

采空区地层变形产生的隧道附加荷载及变形容许值计算与分析

文章分别计算了采空区上方地层弯曲时对隧道产生的附加荷载q1、q2及地层水平应变时对隧道产生的附加荷载qH,并推导出了采空区地层容许弯曲变形和水平应变数值.结果表明,现行交通部《采空区公路设计与施工技术细则》规定的采空区地基容许变形值较为笼统且偏大,结构偏于不安全.最后,文章根据计算结果对比,对不同围岩级别提出了更严格、更安全、更有针对性和可操作性的隧道对采空区地层变形限制要求,以供广大隧道工作者参考使用.     

汽车电平衡的设计计算与验证方法

介绍汽车电平衡的设计方法,具体说明汽车电平衡性能所涉及关键零部件的计算选型,列出汽车电平衡的验证方法,并结合实际试验车型对测试结果进行分析。     

Fatigue life prediction of a rubber material based on dynamic crack growth considering shear effect

This paper suggests a fatigue life calculation method (A fatigue life calculation method is suggested) for rubber components based on the dynamic crack growth considering shear effect. Dynamic tearing tests were carried out, and the crack length was measured using an optical microscope to calculate the dynamic crack growth rate which characterizes and determines the fatigue life. The algorithm was numerically implemented in finite element code, ABAQUS standard, by using the user subroutine and applied to several rubber components. In the finite element analysis, deformation mode of an element was classified into tension and shear, and a weighting factor was multiplied to a strain energy density according to the degree of shear strain. Tension and compression of an elliptic dumbbell specimen was simulated in order to verify the material parameters of the suggested fatigue life prediction equation and to enhance the reliability of the algorithm. Finally, the fatigue life of a vehicle suspension bushing was calculated and compared with test. There were good agreements in the failure location and the magnitude of the fatigue life.     

Analysis of the shifting behavior of a novel clutchless geared smart transmission

Conventional geared transmissions use some kinds of clutches to control the power flow from an internal combustion engine to the driveline while shifting gears. However, the shifting performance is seriously affected by the clutch engagement and an unavoidable drop in the torque may occur when the clutch is disconnected. Moreover, wear of the clutch, the need for hydraulic equipment, and the load limit may together aggravate the limits of the clutch system. For this reason, as a novel transmission without a clutch, the clutchless geared smart transmission (henceforth CGST) is proposed by our research team. The CGST controls the power flow in a multiple-input gear-train by controlling the electric motor attached to the planetary gear system. However, no CGST has been realized in an actual vehicle thus far, and the performance has been predicted only theoretically. In this research, we analyzed the achievable performance based on a developed CGST dynamic model with a typical CGST structure. In addition, a CGST gear-shifting algorithm is proposed for use with the dynamic model. From the simulation results, the CGST does not show an abrupt drop in its torque or oscillation while shifting gears due to the absence of a discontinuous power flow. The developed dynamic model can serve as a performance reference for the CGST. Moreover, it can be used as a simulation tool for developing a gear-shifting control logic scheme.     

SX5256DH434PHEV型混合动力环卫车动力系统浅谈

近年来,随着石油资源的消耗,人类生存环境的不断恶化,发展绿色能源交通已刻不容缓。节约能源,低排放甚至零排放的电动汽车成为解决问题的手段。而混合动力汽车作为传统汽车到纯电动汽车之间的过渡类型成为现阶段新能源汽车的主力军。混合动力汽车较传统汽车有着良好的燃油经济性,较低的油耗和良好的排放特性。本文从混合动力重型汽车工作原理出发,依据汽车设计原则,介绍了陕汽集团SX5256DH434PHEV型混合动力环卫车驱动模式,并在此基础上确定了整车底盘驱动动力分配机构,为我国混合动力汽车的发展提供借鉴。     

关于某动力总成悬置支架的优化设计

本文针对某动力总成悬置系统NVH性能道路试验中,全油门缓加速工况受发动机频率激振影响,某悬置主动侧支架发生共振,导致在260Hz左右产生车内结构噪声的情况,采用hypermech-nastran有限元软件建立该悬置支架的有限元模型对其模态进行分析,并根据模态分析结果对该悬置支架设计优化。最后通过道路试验结果验证悬置支架结构设计优化的正确性,可使整车在全油门缓加速工况260Hz附近的振动和车内噪声明显降低。