有限供给条件下的深圳大鹏交通出行链研究

大鹏城郊旅游交通组织是深圳城市交通不可回避的问题。在大鹏新区成立的当下,城市开发的冲动催生交通基础设施建设规模有不断提升的趋势,势必与大鹏"保护为先"的发展思路产生对立,大鹏的交通何去何从?从梳理不同城区功能发展诉求下交通出行链构建角度,探寻有限供给下的新区交通系统构建方式。     

隧道竖井连接部扩大断面支座支顶台车施工技术

通过通省隧道2#通风竖井井底左洞送风口扩大断面的施工实践,介绍了扩大断面挑顶扩挖、二衬台车改装加高以及顶隔板横梁安装加固等一些特殊的施工技术。既保证了隧道的施工安全和工程质量,也最大限度的减少了施工成本和加快了施工进度,取得了较好的经济效益和社会效益。对类似工程可提供借鉴。     

《深圳市综合交通体系规划((2013—2030)》编制探索——以更具竞争力、可持续的综合交通体系促进城市转型发展

通过回顾评价深圳市历次综合交通体系规划的得失,分析城市转型对于综合交通体系的挑战以及新形势下综合交通体系规划的定位。以《深圳市综合交通体系规划(2013—2030)》为例,对规划编制的内容和方法开展研究,具体包括:转型导向的交通发展目标与指标体系、一体化的综合交通体系组织、立足区域协作的整体交通战略、与组团结构相匹配的交通分区组织、与城市功能布局的协调互动、注重协同的交通管控政策,以及应对大数据的智能交通策略等。最后介绍规划编制组织特点并提出城市转型期综合交通体系规划的进一步思考。     

循环载荷下考虑累积塑性影响的含中心穿透裂纹板CTOD研究

裂纹尖端张开位移(CTOD)是评估结构材料韧性以及分析低周疲劳破坏引起的裂纹扩展的重要参量。结合Dugdale模型,以裂纹尖端累积塑性应变为控制参量,提出了一个循环载荷下含裂纹船体板的CTOD计算模型;利用有限元法模拟了裂纹尖端累积塑性应变、平均应力、裂纹长度等相关因素影响;结合最小二乘法拟合出了基于累积塑性塑性应变、平均应力比以及裂纹长度的两阶多项式。研究表明,基于累积塑性应变的CTOD计算模型为正确评估循环载荷下船体板的累积塑性破坏提供了一种新途径。     

Virtual prototype simulation on underwater hydraulic impingement shovel

The virtual prototype technology is applied to the design of the hydraulic impingement shovel, which is to increase the reliability of the design. The work principle of hydraulic impingement shovel is expatiated, and its dynamic equations are established. The 3D model of virtual prototype is built by PRO/E. Then the couple between the mechanical body of prototype and the hydraulic system is completed by virtue of ADAMS. Finally, the simulation is made on the virtual prototype. The simulation results show that the design of underwater hydraulic impingement shovel is rational. The virtual prototype technology could lay sound foundation of successful manufacturing of physical prototype for the first time and offer highly effective and feasible means for the design and production of underwater equipments.     

Experimental study on the width of the turbulent area around bridge pier

At present, the method of calculating the turbulent flow width around the bridge pier is not given in the "Standard for Inland River Navigation" (GB50139-2004) in China, and the bridge designer usually increases the bridge span in order to ensure the navigation safety, which increases both of the structural design difficulty and the project investments. Therefore, it is extremely essential to give a research on the turbulent flow width around the bridge pier. Through the experiments of the fixed bed and the mobile bed, the factors influencing the turbulent flow width around the bridge pier have been analyzed, such as the approaching flow speed, the water depth, the angles between the bridge pier and the flow direction, the sizes of bridge pier, the shapes of the bridge pier, and the scouring around the bridge pier, etc. Through applying the dimension analytic method to the measured data, the formula of calculating the turbulent flow width around the bridge pier is then inferred.     

Using a SVM to evaluate damage to vibration isolators in an elastic raft system

Predicting damage to vibration isolators in a raft experiencing heavy shock loadings from explosions is an important task when designing a raft system. It is also vital to be able to research the vulnerability of heavily shocked floating rafts unreliable, especially when the allowable values The conventional approach to prediction has been or ultimate values of vibration isolators of supposedly uniform standard in a raft actually have differing and uncertain values due to defective workmanship. A new model for predicting damage to vibration isolators in a shocked floating raft system is presented in this paper. It is based on a support vector machine（SVM）, which uses Artificial Intelligence to characterize complicated nonlinear mapping between the impacting environment and damage to the vibration isolators. The effectiveness of the new method for predicting damage was illustrated by numerical simulations, and shown to be effective when relevant parameters of the model were chosen reasonably. The effect determining parameters, including kernel function and penalty factors, has on prediction results is also discussed. It can be concluded that the SVM will probably become a valid tool to study damage or vulnerability in a shocked raft system.     

A second order volume of fluid （VOF） scheme for numerical simulation of 2-D breaking waves

Among all environmental forces acting on ocean structures and marine vessels, those resulting from wave impacts are likely to yield the highest loads. Being highly nonlinear, transient and complex, a theoretical analysis of their impact would be impossible without numerical simulations. In this paper, a pressure-split two-stage numerical algorithm is proposed based on Volume Of Fluid (VOF) methodology. The algorithm is characterized by introduction of two pressures at each half and full cycle time step, and thus it is a second-order accurate algorithm in time. A simplified second-order Godunov-type solver is used for the continuity equations. The method is applied to simulation of breaking waves in a 2-D water tank, and a qualitative comparison with experimental photo observations is made. Quite consistent results are observed between simulations and experiments. Commercially available software and Boundary Integral Method (BIM) have also been used to simulate the same problem. The results from present code and BIM are in good agreement with respect to breaking location and timing, while the results obtained from the commercial software which is only first-order accurate in time has clearly showed a temporal and spatial lag, verifying the need to use a higher order numerical scheme.     

42 V电控发动机冷却系统的研究

冷却系统是发动机的重要组成部分,分析了传统冷却系统的不足,设计基于模糊控制的42V发动机电子控制冷却系统,该冷却系统能够实现散热风扇的无级变速,使发动机工作在最佳温度,使之更经济、更环保,给出了模糊控制器的仿真结果,对比试验结果显示较传统冷却系统性能优越。     

基于ADAMS的双横臂独立悬架的仿真分析及优化设计

在现有的汽车前悬架数据的基础上,用ADAM S/VIEW模块建立悬架模型,并对模型进行仿真计算,研究分析汽车运动中悬架随车轮上下跳动时定位参数的变化规律,评价悬架数据合理性。采用优化分析对悬架不合理数据进行优化,进一步改善悬架系统性能,以提高产品开发质量。