自主机器人的噪声影响及其消解策略的研究

该文针对典型的觅食任务,以计算机仿真为手段,直观地揭示噪声对机器人系统性能的影响.在此基础上,提出了以过程奖赏（process reward）代替传统的结果奖赏（result reward）,并与优先扫除（prioritized sweeping）的强化学习算法结合作为噪声消解策略.然后与基于结果奖赏的Q学习算法（Q-learning）等其它四种算法进行比较,结果表明基于过程奖赏和优先扫除的强化学习算法能显著降低噪声的影响,提高了系统整体性能.     

Experimental study of pollutant accumulation on an urban road surface

An understanding of pollutant characteristics on impervious surfaces is essential to estimate pollutant washoff characteristics and to design methods to minimise the impacts of pollutants on the environment. This paper presents data on surface pollutant characteristics on an urban road surface in Melbourne, Australia, from samples collected over a 36 day period. The data indicate that buildup over the dry days occurs relatively quickly after a rain event, but slows down after several days as redistribution occurs. The surface pollutant also becomes finer over the dry days as it is disintegrated. The washoff of surface pollutant is dependent on the rainfall and runoff characteristics, but the results here show that common storms only remove a small proportion of the total surface pollutant load. The data also show that street sweeping may have an adverse impact on pollutant washoff because the street sweeper releases the finer material but only removes some of them, making the fine sediment available for washoff by the next storm. The data also show that most of the nutrients are attached to the finer sediments, and to effectively reduce nutrient loads in particulates, treatment facilities must be able to remove the finer particles (down to 50 μm for TP and down to 10 μm for TN), and not just the total sediment or suspended solid load.     

混凝-超滤去除腐殖酸的试验研究

进行了直接超滤和混凝－超滤组合工艺对腐殖酸的去除效果和膜污染状况的试验。结果表明，超滤前另混凝土预处理对腐殖酸的DOC和UV254的去除率分别从28％、40％提高到53％、78％。同时高效液相色普（HPLC）分析表明，混凝－超滤组合工艺对分子质量＜6000u的有机物的去除率提高幅度更为显著。混凝－超滤组合工艺的最佳pH值条件pH=7,通过卷扫混凝使小分子有机物结合成微絮体，降低了膜孔污染，使超滤保持了较同的渗透通量。     

布袋除尘系统设计中的两个问题

指出了当前在布袋除尘系统设计工作中,存在着不能正确选定过滤风速、不能正确确定大气反吹布袋除尘器的反吹风压的问题;分析了产生问题的原因;提出了作者的看法。     

氧化铝料箱排气管冒料分析及对策

针对电解槽氧化铝料箱排气管“冒料”现象，从料箱和下料器结构、工作过程及工作条件等方面分析，找出“冒料”原因，采取措施，取得了明显的效果。     

高速公路多功能电动养护车的设计及可行性分析

高速公路的快速发展,对其养护提出了更高的要求,应用新型高速公路电动养护车将较好地解决人工养护生产率低,劳动强度大的问题,为保证良好的路容路貌提供了有力地保障.     

基于局部Lax-Friedrichs通量分裂格式的透视SFS

提出了一种基于局部Lax-Friedrichs通量分裂格式的快速扫描算法,用以解决透视投影下的SFS问题。先对透视投影SFS进行建模,将其转换为静态Hamilton-Jacobi方程,再结合局部Lax-Friedrichs通量分裂格式和快速扫描算法对静态Hamilton-Jacobi方程进行求解,从而得到物体表面。本文算法可以用于非凸Hamiltonian函数的情况,提高了局部分析能力,不需要对初始高度进行估计,且算法简单,易于实现。对合成图像和实际图像的实验表明本文算法可以得到较好的透视投影SFS的恢复结果。      

Determination of the Normal Contact Stiffness and Integration Time Step for the Finite Element Modeling of Bristle-Surface Interaction

In finite element modeling of impact, it is necessary to define appropriate values of the normal contact stiffness, K_n, and the Integration Time Step (ITS). Because impacts are usually of very short duration, very small ITSs are required. Moreover, the selection of a suitable value of K_n is a critical issue, as the impact behavior depends dramatically on this parameter. In this work, a number of experimental tests and finite element analyses have been performed in order to obtain an appropriate value of K_n for the interaction between a bristle of a gutter brush for road sweeping and a concrete surface. Furthermore, a suitable ITS is determined. The experiments consist of releasing a steel bristle that is placed vertically at a certain distance from a concrete surface and tracking the impact. Similarly, in the finite element analyses, a beam is modeled in free fall and impacting a surface; contact and target elements are attached to the beam and the surface, respectively. The results of the experiments and the modeling are integrated through the principle of conservation of energy, the principle of linear impulse and momentum, and Newton’s second law. The results demonstrate that, for the case studied, K_n and the impact time tend to be independent of the velocity just before impact and that K_n has a very large variation, as concrete is a composite material with a rough surface. Also, the ratio between the largest height of the bristle after impact and the initial height tends to be constant.     

基于时序及相关检测的调频引信抗扫频干扰方法

针对调频引信抗扫频干扰能力差的问题,建立扫频干扰模型,分析扫频干扰下调频引信失效机理,提出了基于时序及相关检测的调频引信抗扫频干扰方法;综合利用弹目距离信息、双通道时序信息及时间间隔信息作为调频引信输出起爆控制信号的判决条件;仿真验证了算法的可行性,并进行了硬件实现。仿真及实测结果表明,与现有调频引信相比,基于时序及相关检测的调频引信抗扫频干扰方法,有效地提高了调频引信抗扫频干扰能力及引信定距精度,算法复杂度和实时性满足引信要求。     

脊型谐振腔的改进设计

脊型加速器最关键的部件是脊型谐振腔,本文根据射频性能对其进行了电磁场模拟与优化。为了进一步提高腔体的Q值和分路阻抗,提出了取消电极头。采用约束变量参数扫描方法对腔体机械参数进行了优化,在保持腔体谐振频率不变的情况下,找到了最优或合理的机械参数。研究结果表明,束流在谐振腔内加速次数的增加可提高腔体的分路阻抗。