四轮驱动ABS控制方法的分析

以四轮驱动汽车为研究对象,分析了其在差速器锁止时制动防抱死控制过程所出现的问题,归纳总结了四轮驱动ABS控制技术的特点及对制动安全性的影响。     

间歇式沥青搅拌设备称量系统设计

从沥青搅拌设备供料系统到称量系统机构及控制系统设计,全面阐述了影响沥青搅拌设备称量精度的因素及在实际应用中的合理解决办法,并提出沥青搅拌设备称量精度指标要求.     

一种确定高圆簧横向刚度的有效方法

文中将高圆簧简化为等截面弹性直杆，导出高圆簧横向刚度计算式，并用试验结果进行修正，提出高圆横向刚度分析方法。理论分析和试验结果表明：高圆簧横向刚度的大小取愉于高圆簧的自由高度和工作高度，即由其结构几何参数和工作载荷决定。按文中方法确定的高圆簧横向刚度理论值与试验结果间的最大误差不超过１０％，满足工程理论分析要求。     

间歇式沥青拌和站冷料供给系统流量的标定方法

以实例介绍间歇式沥青拌和冷料供给系统流量的标定方法和步骤，以确保冷料供给器按目标配合比准确供料，使沥青混合料的生产配比更加接近目标配比，保证拌和成品料的质量。     

双速搅拌工艺

根据传统二次搅拌理论,提出了混凝土双速搅拌工艺,介绍了双速搅拌工艺的原理及优点,并指出了该工艺的实现方案.该工艺的应用可降低生产成本,提高混凝土的强度和生产率.     

Comparing different contour methods with response-based methods for extreme ship response analysis

Environmental contours are often applied in probabilistic structural reliability analysis to identify extreme environmental conditions that may give rise to extreme loads and responses. They facilitate approximate long term analysis of critical structural responses in situations where computationally heavy and time-consuming response calculations makes full long-term analysis infeasible. The environmental contour method identifies extreme environmental conditions that are expected to give rise to extreme structural response of marine structures. The extreme responses can then be estimated by performing response calculations for environmental conditions along the contours.Response-based analysis is an alternative, where extreme value analysis is performed on the actual response rather than on the environmental conditions. For complex structures, this is often not practical due to computationally heavy response calculations. However, by establishing statistical emulators of the response, using machine learning techniques, one may obtain long time-series of the structural response and use this to estimate extreme responses.In this paper, various contour methods will be compared to response-based estimation of extreme vertical bending moment for a tanker. A response emulator based on Gaussian processes regression with adaptive sampling has been established based on response calculations from a hydrodynamic model. Long time-series of sea-state parameters such as significant wave height and wave period are used to construct N-year environmental contours and the extreme N-year response is estimated from numerical calculations for identified sea states. At the same time, the response emulator is applied on the time series to provide long time-series of structural response, in this case vertical bending moment of a tanker. Extreme value analysis is then performed directly on the responses to estimate the N-year extreme response. The results from either method will then be compared, and it is possible to evaluate the accuracy of the environmental contour method in estimating the response. Moreover, different contour methods will be compared.     

Optimal placement of omnidirectional sensors in a transportation network for effective emergency response and crash characterization

Rapid motor vehicle crash detection and characterization is possible through the use of Intelligent Transportation Systems (ITS) and sensors are an integral part of any ITS system. The major focus of this paper is on developing optimal placement of accident detecting omnidirectional sensors to maximize incident detection capabilities and provide ample opportunities for data fusion and crash characterization. Both omnidirectional sensors (placed in suitable infrastructure locations) and mobile sensors are part of our analysis. The surrogates used are acoustic sensors (omnidirectional) and Advanced Automated Crash Notification (AACN) sensors (mobile). This data fusion rich placement is achieved through a hybrid optimization model comprising of an explicit–implicit coverage model followed by an evaluation and local search optimization using simulation. The compound explicit–implicit model delivers good initial solutions and improves the detection and data fusion capabilities compared to the explicit model alone. The results of the studies conducted quantify the use of a data fusion capable environment in crash detection scenarios, and the simulation tool developed helps a decision maker evaluate sensor placement strategy.     

美国限速制定方法及启示

为使我国道路限速的制定更为合理,借鉴国外相关经验是必不可少的。总结了美国设置限速时考虑的主要因素、限速设置方法及其适用条件。对美国部分城市的州际道路及主干路的限速实施状况进行了分析,认为测速相机等自动执法设备的辅助使用能够在很大程度上提高驾驶人对限速的遵守程度。在借鉴美国限速方法及实施经验的基础上,指出我国在制定道路相关限速标准时,应结合国情确定限制速度与运行速度、设计速度之间的互动关系,以及限速与安全、执法等之间的关系。然后针对不同的道路类型、等级等特性研究采用不同的限速方案,解决速度区限速取值及不同速度区之间如何平滑过渡衔接等问题,明确了我国限速研究的基础性内容。     

城市混合交通控制设计理念与方法

针对我国城市特有的混合交通特性,在分析城市路网特征和交通流运行特征的基础上,确立了混合交通控制系统设计的基本理念。基于混合交通流理论,建立了城市交通控制的方法体系,包括匝道控制、单点控制、干线协调控制、区域协调控制以及公交优先控制。运用此设计理念与方法开发出的混合交通控制系统（HiCON）,在北京、青岛、福州三地的应用表明：车辆平均延误减少10％～20％,平均行程时间降低5%-10％。     

Simple Identification of Some Coastal Marine Habitats by Modeling with Sea-Chart Data

A simple numerical model was applied to distinguish permanently oxygenated marine sill basins from periodically anoxic basins in Nordland County, northern Norway. Input data are sill depth, width of the tidal channel, sea surface area, and tidal range. The model produces a Topography Tidal Factor (TTF) that seems to be an adequate index correlating with empirical field data when sills have saddle depths <30 m. The depth of the pycnocline, and the oxygen concentration of the basin water increases logarithmically with the calculated TTF value toward an asymptotic level. At TTF ≥0.02 basins are mostly well-oxygenated and have a permanent fauna of epibenthic and hyperbenthic animals. Basins with TTF <0.02 may become anoxic each autumn, which permanently prevents establishment of communities with multi-annual sessile benthos. Low oxygen concentration may also cause seasonal variation in the occurrence of motile species. In tidal channels, the abundance of bivalves and fish, as well as the biodiversity in general, probably increases with TTF. The applied method may be universally valid in regions shaped by glacial erosion but needs to be further developed by more detailed studies.