工程车辆智能换挡规律的仿真

以装载机为研究对象,分析了工程车辆自动变速系统的结构及原理,建立了工程车辆电控自动变速系统组成原理图。针对工程车辆的作业特点,以适应性和在线实时性等综合性能最优为控制目标,确定了工程车辆智能换挡规律控制原则。基于仿人智能模糊控制方法,对换挡规律进行了分析研究,建立了装载机动力传动系统动态仿真模型,并应用Matlab/Simulink软件进行了仿真分析。仿真结果表明,将仿人智能模糊控制方法应用于工程车辆智能变速系统具有可行性。     

Validating the Passenger Traffic Model for Copenhagen

The paper presents a comprehensive validation procedure for the passenger traffic model for Copenhagen based on external data from the Danish national travel survey and traffic counts. The model was validated for the years 2000–2004, with 2004 being of particular interest because the Copenhagen Metro became operational in autumn 2002. We observed that forecasts from the demand sub-models agree well with the data from the 2000 national travel survey, with the mode choice forecasts in particular being a good match with the observed modal split. The results of the 2000 car assignment model matched the observed traffic better than those of the transit assignment model. With respect to the metro forecasts, the model over-predicts metro passenger flows by 10–50%. The wide range of findings from the project resulted in two actions. First, a project was started in January 2005 to upgrade the model’s base trip matrices. Second, a dialog between researchers and the Ministry of Transport has been initiated to discuss the need to upgrade the Copenhagen model, e.g. a switching to an activity-based paradigm and improving assignment procedures.     

风场作用下趸船区域溢油动态模拟研究

以舟山定海港区某油库码头为背景建立了风场作用下的趸船区域溢油动态模型。针对趸船区域可能产生油品溢漏的位置,对趸船区域的溢油运动情况进行了模拟分析。模拟结果显示,当泄漏油品为柴油(850kg/m3,0.003825Pa·s)、泄漏点宽度为0.5m、油品泄漏速度为1m/s时,受风场作用,发生在趸船附近的溢油事故,其溢漏油品不仅随潮水运动流动,还会大量的在码头与岸线之间的区域及码头两端部附近产生积聚。在进行溢油事故快速控制和污油回收时,需要重点针对该区域进行监控防治。     

Road classification for two-wheeled vehicles

This publication presents a three-part road classification system that utilises the vehicle's onboard signals of two-wheeled vehicles. First, a curve estimator was developed to identify and classify road curves. In addition, the curve estimator continuously classifies the road curviness. Second, the road slope was evaluated to determine the hilliness of a given road. Third, a modular road profile estimator has been developed to classify the road profile according to ISO 8608, which utilises the vehicle's transfer functions. The road profile estimator continuously classifies the driven road. The proposed methods for the classification of curviness, hilliness, and road roughness have been validated with measurements. The road classification system enables the collection of vehicle-independent field data of two-wheeled vehicles. The road properties are part of the customer usage profiles which are essential to define vehicle design targets.     

青藤碱对家兔血管平滑肌细胞增殖的影响

目的　研究青藤碱对血管平滑肌细胞增殖作用及 DNA合成的影响。方法　采用内皮素刺激的离体家兔血管平滑肌细胞增殖模型 ,细胞计数 ,氚 -胸腺嘧啶核苷掺入方法。结果　青藤碱明显抑制血管平滑肌细胞增殖反应及 DNA合成 ,呈剂量依赖关系。结论　表明青藤碱具有抗血管平滑肌细胞增殖作用     

基于核心优势识别的汽车4S店服务价值链拓展策略分析

针对中国汽车市场进入服务竞争时代的趋势,在分析汽车4S店所面对后市场竞争环境的基础上,首先提出汽车4S店核心竞争优势的识别方法;而后基于价值链模型提出服务价值链拓展的若干模式,分析汽车4S店核心业务的不同发展策略;最后给出汽车4S店开展未来业务的一些建议。     

Autonomous vehicles in mixed motorway traffic: capacity utilisation,impact and policy implications

In upcoming years, the introduction of autonomous vehicles (AVs) will reshape the transport system. The transition from a regular to an autonomous transport system, however, will take place over many years and lead to a long period with a mixed driving environment where AVs and regular vehicles (RVs) operate side by side. The purpose of this study is to investigate how the utilisation of the road capacity degrades as a function of heterogeneity in congested motorways. The analysis is based on a dedicated traffic simulator, which enables the investigation of complex dynamic spillback from congestion while allowing for different degrees of heterogeneity. The representation of autonomous vehicles is based on a modified intelligent driver model (IIDM) presented by Treiber et al. (Phys Rev E 62(2):1805–1824, 2000) and Treiber and Kesting (Traffic flow dynamics, Springer, Heidelberg, 2013), while the behaviour of drivers of RVs relies on a stochastic version of the IIDM. Three main conclusions stand out. Firstly, it is shown that in an idealised environment in which AVs operate alone, a substantially improved capacity utilisation can be attained. Secondly, when drivers of RVs are mixed with AVs, capacity utilisation degrades very fast as a function of the share of RVs. Thirdly, it is shown that the improved capacity utilisation of AVs comes in the form of reduced travel time and increased throughput, with indications that travel time reductions are the most important. From a strategical planning perspective, the results underline that dedicated lanes are preferable to attain the positive effects of AVs. Specifically, we compare a stylised situation with three lanes with a share of 33% AVs to a situation with two regular lanes and a single dedicated AV lane. The latter represents a tripling in consumer surplus all other things being equal.

     

20000DWT近海散货船概念设计多学科优化

以20 000 DWT近海散货船为研究对象,分别建立以船舶造价、航速、回转性指数、应舵指数为目标的多个船舶概念设计优化数学模型。应用iSIGHT软件对这些数学模型进行集成,采用非支配解排序的多目标遗传算法(NSGA-Ⅱ)求解船舶概念设计多目标问题以获得Pareto解集。优化结果证明了NSGA-Ⅱ算法解决近海散货船优化设计问题的有效性,为解决更复杂工程系统的设计优化问题奠定了基础。     

船体外板大拼接焊缝高效无尘喷砂除锈器

为适应船体外板大拼接焊缝大范围高效环保喷砂除锈,开发大腔室多枪旋转高效无尘喷砂器,并对其气固两相流特性进行研究.将整个喷砂过程置于一个直径100.0 m m以上的密闭腔室,采用单/双喷砂枪通过电机高速旋转喷枪对工件表面进行喷砂,并基于真空负压对反弹的磨料和冲蚀掉的铁锈、油污、粉尘等进行回收、分离和循环再利用.采用基于欧...     

复杂结构船舶船体托盘划分方案

基于船体零件的托盘化管理在主船体建造中的重要性，结合实际生产流程，确立以中组立为基础的新的托盘划分方案，通过实船检验，可有效提高零件的流转效率，对大型复杂结构船舶的主船体建造具有较强的指导意义。