动力传动系统的双微处理器联合控制

介绍了基于双微处理器联合控制的动力传动一体化控制系统。控制系统是由发动机控制、自动换挡控制、液力变矩器闭锁闭环控制、换挡品质控制等部分组成。最后给出了动力传动一体化控制系统的装车试验结果。从试验结果可以看出，动力传动一体化控制系统的设计是有效的。     

On the role played by turbulence closures in hull shape optimization at model and full scale

 The practical use of automated computational fluid dynamics (CFD)-based design tools in the ship-building industry requires powerful flow solvers which are able to take into account realistic geometries as well as complex physical phenomena, such as turbulence. A shape optimization tool is developed in this framework. A derivative-free optimizer, yielding both flexibility and robustness, is preferred to the classical gradient-based method, which is more difficult to implement and is still limited to only moderately complex problems. The flow solver included in the design procedure solves the incompressible Reynolds-averaged Navier–Stokes equations on unstructured grids using a finite-volume formulation involving several near-wall low-Reynolds-number turbulence models. The design tool is used to optimize the stern of a modern hull shape at model and full scale, with different purposes being considered. More precisely, the drag reduction and the homogenization of the flow in the wake are expected by controlling the longitudinal vortex generated. Our interest is particularly focused on the influence of turbulence modeling in the design process. The effects of a two-equation model based on the eddy-viscosity assumption and a second-order closure relying on the Reynolds stress transport equations are compared. Received: September 24, 2002 / Accepted: April 14, 2003 RID="*" Acknowledgment. The authors thank the scientific committee of CINES (project dmn2050) for the attribution of CPU time.     

九江长江公路大桥主塔钢锚梁施工技术

文章结合九江长江公路大桥,介绍了主塔钢锚梁施工组织设计中需要考虑的主要目标,施工程序步骤以及施工精度控制措施,可供今后类似桥梁的施工参考.     

Radiosensitivity of β-elemene on rabbit VX2 renal transplant carcinoma model

Objective To investigate the effects of low dosage of β-elemene on the radiosensitivity of rabbit VX2 renal transplant carcinoma model. Methods We took the rabbit VX2 renal transplant carcinoma as the model. Experimental rabbits were divided into three groups: the control group, the radiation group, and the radiation +β-elemene (radiosensitivity) group. The change of tumor was observed by Spiral CT and B ultrasound to compare its regrowth period. The tumor was measured by light microscopy and electron microscopy. Results The tumor in radiosensitivity group was restrained obviously and the sensitization enhancement ratio (SER) of β-elemene was 1.89. Different apoptosis was observed under transmission electron microscopy. Conclusion Low dosage β-elemene can enhance the radiosensitivity of rabbit VX2 renal transplant carcinoma model and induce the apoptosis of tumor cells, but the mechanism needs further study. It promotes apoptosis in mechanisms in vitro.     

RWLS-I型便携式铁道车辆智能轮重仪的设计

针对铁路车辆的超载、偏载问题,研制RW:S-I型便携式铁道车辆钾能轮重仪.整机采用一体化结构、铝合金机架、微电机驱动.利用电测法测量举升力,具有数字显示输出、数值标定等功能,提高了测定精度.轮重仪总质量约10 kg,操作方便,可降低劳动强度.     

地铁列车运行调整策略选择与制约因素分析

地铁突发事件带来最直接的影响就是列车运行秩序紊乱,客流积压。在制定列车运行调整方案的过程中,不仅要综合运用各种调整策略,而且要考虑各种制约因素,尤其是对各种不确定因素的判断,才能使调整方案更加科学、合理。介绍了地铁列车运行调整的各种策略和方法,分析了各种调整策略选择的制约因素,并结合实际案例分析不同调整策略的综合应用与策略选择。     

轨道交通通信系统的传输技市比较

为了更好地推荐轨道交通领域对传输网络的建设方案,构建健壮、多业务、弹性的传送平台,提出构建弹性可重购(3R:Reconfigurable,Resilient,Reliable)、高效性价比、统一的多业务传递平台的解决方案.对主流传输技术进行了详细比较,认为弹性可重购3R多业务传送平台满足轨道交通分拆和延长分期建设的要求.展望了未来的承载网技术,分析和比较了MSTP(多业务传送平台)和IP传送平台.     

城市轨道交通枢纽综合开发功能配置及建设模式

当前我国城市轨道交通枢纽存在交通衔接功能不全,用地功能单一,建设模式不清晰等诸多问题,在一定程度上影响了轨道交通功效的发挥和城市用地功能的优化.在分析轨道交通枢纽分类及其综合开发设施分类的基础上,采用定性与定量相结合的方法,探讨不同类型的轨道交通枢纽进行综合开发时,如何配置与之相适应的各种功能的交通衔接设施和兼容性设施...     

南京地铁运营电耗分析及改进措施

随着地铁开通线路的增多,运营成本中电费所占的比例大幅度增加。结合南京地铁运营分公司自身的发展需要及现有的运营管理模式,在确保安全运营与服务质量不受影响的前提下,通过技术手段和精细化管理,降低不必要的能源消耗,减少用能浪费,实现合理用能,科学节能。     

子结构组合系统分析中的分步计算法——用试验模态参数进行汽车整车动力学模型建模的探讨

本文应用子结构组合模态综合法,利用试验模态数据,在计算机上建立了一个包括汽车20Hz之前各阶弹性模态和刚体模态的整车动力学模型。为容纳尽可能多的模态数和测点数,提出了在模型计算过程中的分步计算法。