Measurement and mathematical model of a driver's intermittent compensatory steering control

The compensatory (feedback) component of a human driver's steering control is examined. In particular, the effect of the cognitive process is studied. Model predictive control theory is used to implement models of intermittency in cognitive processing. Experiments using a fixed-base driving simulator with periodic occlusion of the visual display are used to reveal the nature of the driver's steering behaviour. An intermittent serial-ballistic control strategy is found to match the measured behaviour better than intermittent zero-order hold or continuous control. The findings may enable some insight to driver-vehicle interaction and vehicle handling qualities.     

Roll and pitch independently tuned interconnected suspension: modelling and dynamic analysis

In this paper, a roll and pitch independently tuned hydraulically interconnected passive suspension is presented. Due to decoupling of vibration modes and the improved lateral and longitudinal stability, the stiffness of individual suspension spring can be reduced for improving ride comfort and road grip. A generalised 14 degree-of-freedom nonlinear vehicle model with anti-roll bars is established to investigate the vehicle ride and handling dynamic responses. The nonlinear fluidic model of the hydraulically interconnected suspension is developed and integrated with the full vehicle model to investigate the anti-roll and anti-pitch characteristics. Time domain analysis of the vehicle model with the proposed suspension is conducted under different road excitations and steering/braking manoeuvres. The dynamic responses are compared with conventional suspensions to demonstrate the potential of enhanced ride and handling performance. The results illustrate the model-decoupling property of the hydraulically interconnected system. The anti-roll and anti-pitch performance could be tuned independently by the interconnected systems. With the improved anti-roll and anti-pitch characteristics, the bounce stiffness and ride damping can be optimised for better ride comfort and tyre grip.     

An optimal torque distribution control strategy for four-independent wheel drive electric vehicles

In this paper, an optimal torque distribution approach is proposed for electric vehicle equipped with four independent wheel motors to improve vehicle handling and stability performance. A novel objective function is formulated which works in a multifunctional way by considering the interference among different performance indices: forces and moment errors at the centre of gravity of the vehicle, actuator control efforts and tyre workload usage. To adapt different driving conditions, a weighting factors tuning scheme is designed to adjust the relative weight of each performance in the objective function. The effectiveness of the proposed optimal torque distribution is evaluated by simulations with CarSim and Matlab/Simulink. The simulation results under different driving scenarios indicate that the proposed control strategy can effectively improve the vehicle handling and stability even in slippery road conditions.     

中国南海ASDD深水试验井中的锚泊设计与作业(英文)

Mooring systems play an important role for semi-submersible rigs that drill in deepwater.A detailed analysis was carried out on the mooring of a semi-submersible rig that conducted a trial well drilling at a deepwater location in the South China Sea in 2009.The rig was 30 years old and had a shallow platform with a designed maximum operating water depth of 457 m.Following the mooring analysis,a mooring design was given that requires upgrading of the rig’s original mooring system.The upgrade included several innovations,such as installing eight larger anchors,i.e.replacing the original anchors and inserting an additional 600 m of steel wires with the existing chains.All this was done to enhance the mooring capability of the rig in order for the rig to be held in position to conduct drilling at a water depth of 476 m.The overall duration of the drilling was 50 days and the upgraded mooring system proved to be efficient in achieving the goal of keeping the rig stationary while it was drilling the trial well in the South China Sea.This successful campaign demonstrates that an older semi-submersible rig can take on drilling in deep water after careful design and proper upgrading and modification to the original mooring system.     

秦皇岛港煤炭装卸设备调研和建议

秦皇岛港自1970年代末期开始筹建煤炭码头一期工程。在此后近30年中,先后建成了煤炭码头一至五期工程。港口设备数量多、时间跨度大、型式多样、型号齐全。对秦港煤一期至煤五期所有码头的装卸设备进行了考察。在考察设备的基础上,对于秦皇岛港目前的设备布局、使用情况、性能等进行了细致的分析研究,并提出了若干建议。以期对将来秦港的设备更新以及相关港口有一定的借鉴意义。     

煤码头装卸系统仿真优化研究

为了提高装卸效率,台州发电厂煤炭专用码头对煤炭装卸工艺进行革新,建立仿真优化模型。介绍台州发电厂仿真优化的基本原理和煤炭装卸仿真系统的设计。着重介绍电厂煤码头装卸工艺系统优化的方法。此方案将有效提高煤炭装卸作业效率和码头营运效率。     

针对现阶段公路招投标相关问题的探讨

公路工程招投标是一项在坚持"公开、公平、竞争、择优"的原则下进行的经济活动,实行招投标对工程造价控制,工程质量控制有着积极的作用。在建筑市场内引入竞争机制,促使建筑企业在竞争中寻找差距,以便改善经营管理,提高综合实力。该文分析了当前招投标市场出现的问题,有针对性地提出若干处理方式及有关投标技巧的建议,可供有关单位参考。     

探地雷达在旧路改造病害调查中的应用

文章结合工程实例,分别描述了探地雷达在探测路面混凝土布筋及板底脱空情况中的应用,指出了相应的雷达图和波形特征,介绍了探地雷达基本原理和工作方法,特别是天线阵技术在旧路改造路况病害调查检测中的应用。     

Multioutput analysis of cargo handling firms: An application to a Spanish port

Cargo handling in ports is a multioutput activity, as freight can arrive in many forms such as containers, bulk, rolling stock, or non-containerised general cargo. In this paper, the operation of cargo handling firms in a Spanish port is analysed through the estimation of a multioutput cost model that uses monthly data on three representative firms located at the Las Palmas port. This permits the calculation of product specific marginal costs, economies of scale (general and by firm) and economies of scope, which help identifying optimal pricing policies and the potential cost advantages of increasing production.     

驾驶员PO预瞄模型参数的时域辨识

本文通过斜坡响应不变法实现离荼到连续传递函数间的转换，运用Ｍａｒｑｕａｒｄｔ阻尼最小二乘法辨识驾驶员ＰＯ预瞄模型的物理参数。辨识结果中，当信噪比为２０ｄＢ、４ｄＢ时，最大偏差分别为１．６％及１０％，从而表明斜坡响应不变法具有很高的辨识精度，且因采用阻尼最小二乘法致使物理参数识精度进一步提高。