基于“作业面”模式下集卡配置的仿真研究

为了合理利用集装箱码头的固有资源,提高码头的作业效率,通过集卡调度优化模型算出集卡的最优行驶路径并带入仿真模型中对案例进行分析,得出了在“作业面”模式下集卡配置量与码头作业效率及集卡阻塞时间之间的关系,旨在使码头的装卸效率和资源的浪费状况达到可接受的平衡状态而给出集卡合理配置量的建议。     

大鼠海马神经元自发放电对皮下注射福尔马林的反应

采用玻璃微电极细胞外记录法，观察了清醒完整大鼠海马神经元自发放电对皮下注射福尔马林的反应。结呆显示，在海马CA2／CA3区可记录到痛兴奋、痛抑制和非痛敏三种神经元。同侧前爪皮下注射福尔马林后，痛兴奋神经元的自发放电显著增多，而痛抑制神经元的自发放电显著减少，这种变化在给予福尔马林后30min左右达到最大值，在60min左右恢复到对照水平；但在给予福尔马林后，非痛敏神经元的自发放电无明显变化。以上实验结果提供了在福尔马林痛模型中，海马在痛感受或痛反应过程中发挥一定作用的电生理证据。     

风化泥质板岩路堤工程性状的模型试验研究

介绍了泥质板岩全风化及强风化料作为高速公路、高速铁路路堤的室内模型试验研究,采用不同的颗粒级配、不同的含水量,通过施加不同的竖向荷载作用于模型路堤,获取了路堤面板的沉降以及堤内应力、应变、土压力值和变形性状以及模型路堤的极限承载力等,试验结果表明模型路堤内的应力、应变和沉降位移随堤面竖向荷载、含水量和颗粒粒径不同而变化。它将对软岩风化料填筑高速铁路路堤设计、施工与质量控制起到一定的借鉴作用。     

遂渝铁路无碴轨道桩板结构路基大比例动态模型试验研究

土质路基上的无碴轨道在国外高速铁路上已得到广泛应用,而在我国却处于刚起步阶段。桩板结构路基是土质路基上无碴轨道的一种新型结构形式,其设计及计算还不成熟。在遂渝铁路土质路基上无碴轨道综合试验段桩板结构设计方案的基础上,对此类结构进行大比例动态模型试验研究,希望为此类结构的设计及工程应用提供参考。     

基于"当前"统计模型的机动目标运动要素解算

在避碰过程中,舰船一般处于机动状态.因而,对机动目标运动要素解算的精度直接影响到避碰的效果.通过对多种模型的比较,选用了"当前"统计模型,"当前"统计模型相对于其他模型能够更为真实地反映目标的机动变化.仿真结果表明,此算法收敛迅速并有较高精度,其解算所得的目标运动要素能够满足舰船避碰等实用要求.     

Experimental study on the nonlinear pressure acting on a high-speed vessel in regular waves

It is well known that the hydrodynamic responses of a high-speed vessel traveling in regular head waves of even moderate wave height can show significant nonlinear behavior, and so linear statistical techniques become insufficient for predicting the statistics of responses in irregular waves. On the other hand, it has been shown that an approximate third-order Volterra model is applicable to handling the statistics of some nonlinear seakeeping problems, such as motions and vertical hull girder loads. In the present study, the focus is on the nonlinear behavior of the pressure responses of the hull surface, especially on the pressures acting on alternately wet and dry areas near the waterline and on the bow zone with high deadrise angles that may be subject to slight impact and water pile-up effects. To clarify the validity of applying Volterra modeling to this problem, a series of experiments in regular and irregular head waves were carried out, and approximate third-order and fifth-order Volterra models with the proposed algorithm for finding frequency response functions (FRFs) were applied as a means of validation. In the present article, the first part of the validation was performed using experimental data in regular waves. It was confirmed that the third-order Volterra model has adequate accuracy to simulate deterministically the variation of pressure responses in regular waves of different wave steepness up to a wave amplitude to wavelength ratio of 0.01 even for the highly nonlinear pressures acting on the above-mentioned areas of the hull surface.     

太平洋航线集装箱货流量GM(1,1)-马尔可夫链预测方法探讨

运用灰色系统理论对太平洋航线集装箱货流量进行定量预测,并结合马尔可夫预测方法对航线运量进行定性分析,达到定量与定性预测相结合的目的,使预测结果更加合理。采用马尔可夫链划分系统的状态,得出状态转移概率矩阵,分析了太平洋航线集装箱货流量的发展变化区间并预测集装箱航运市场的发展前景。     

时变胶系统的建模与控制

时间/压力型流体点胶技术在半导体封装过程中有着广泛的应用。由于胶液的非牛顿特性和点胶过程的时变特性,很难建立精确实用的点胶模型。本文通过分析过程参数(胶体体积)变化对系统性能的影响,提出了点胶过程分段变参数模型,并利用该模型对实际点胶系统进行了分段控制。仿真和实验验证了模型与控制的有效性。     

Hybrid neural network model for history-dependent automotive shock absorbers

The method of numerical multi-body simulation is an often used and well-understood development tool in the automotive industry. In order to reproduce the ride comfort or handling behaviour of vehicles, mathematical models have to be built up. To achieve accurate simulation results, highly detailed component models are required. However, the formulation of appropriate physically-based model equations of complex automotive components (e.g. air springs, shock absorbers, rubber bearings, tyres, etc.) can be very difficult. To handle this, empirical modelling methods have been developed. Simple algebraic equations are used to describe complex system behaviour. This simplification is very effective, although it largely ignores the natural laws of mechanics and thermodynamics but is still capable to predict the component response. This article illustrates how to take advantage of this approach in numerical simulations. We describe the development of a hybrid automotive shock absorber model based on both spline and neural network (NN) approaches. By combining these different approaches, an accurate model is achieved without loss of variability. Non-isothermal laboratory force-displacement measurements of an automotive shock absorber are being used to estimate the parameters of the NN. As shown, the model replicates the measured data with sufficient accuracy, especially the hysteresis. Finally, we present a set of quarter-car simulations with a built-in hybrid NN shock absorber.     

弧形防浪墙波浪力的试验研究

在斜坡式防浪建筑物中,为满足越浪与稳定要求,减少工程投资,常在堤顶设置防浪墙。通过三分力天平对常用的直立式、不同墙底高程和墙高组合下的圆弧式防浪墙进行物理模型试验,直接测量作用其上的波浪力,分析不同形式下防浪墙的整体稳定性,讨论防浪墙形式引起的波浪力的变化关系。