摘要：针对智能车辆在结构化道路上,处理动态复杂场景能力较弱以及实时性差的问题,基于可达集的方法设计一种分层式时空耦合的轨迹规划方法,完成车辆在动态不确定场景下的轨迹规划。首先,根据自车与周围的障碍物状态信息,预测障碍物在未来一段时间内的位置分布概率,基于可达集的方法计算各时刻的可达区域,得到最优行驶走廊及一条初始轨迹。其次,利用二次规划的方法在最优行驶走廊内根据初始轨迹进行优化,求解出一条平滑轨迹,并对该轨迹进行跟踪行驶。最后,利用PreScan、CarSim和Matlab软件搭建仿真平台,在动态复杂交通场景下进行仿真分析,并在实车平台上进行避障测试。结果表明,所设计的规划方法能够有效处理动态不确定场景,在保证安全性的前提下能够规划出高效的通行轨迹,同时也能兼顾预测准确度与实时性。

摘要：Quasi-two dimensional(2D)perovskites have emerged as a promising class of materials due to their remarkable photoluminescence efficiency,which stems from their exceptionally high exciton binding *** spatial confinement of excitons within smaller grain sizes could enhance the formation of biexcitons leading to higher radiative recombination ***,the synthesis of high-quality quasi-2D perovskite thin films with controllable grain sizes remains a challenging *** this study,we present a facile method for achieving quasi-2D perovskite thin films with controllable grain sizes ranging from 500 to 900 *** is accomplished by intermediate phase engineering during the film fabrication *** results demonstrate that quasi-2D perovskite films with smaller grain sizes exhibit more efficient bound exciton generation and a reduced stimulated emission threshold down to 15.89µJ cm^(−2).Furthermore,femtosecond transient absorption measurements reveal that the decay time of bound excitons is shorter in quasi-2D perovskites with smaller grain sizes compared to that of those with larger grains at the same pump density,which is 230.5 *** observation suggests a more efficient exciton recombination process in the smaller grain size *** findings would offer a promising approach for the development of efficient bound exciton lasers.

摘要：如何在极限工况下合理地利用耦合的轮胎力,实现轨迹跟踪和运动稳定性的协同优化是当前智能汽车控制的难题之一。为了在保证智能车辆行驶稳定性的前提下提高对期望轨迹的跟踪精度,作者提出了一种基于运动学前馈模型的轨迹跟踪和底盘动力学稳定性协调的控制框架。首先,介绍了基于多点预瞄的四轮转向车辆-道路系统动力学模型;其次,基于LQR最优控制提出了一种四轮转向轨迹跟踪反馈控制器;再次,设计了一种基于滑模控制的底盘稳定性集成控制方法;同时,以轮胎侧偏特性作为切换门限进行轨迹跟踪与稳定性控制的协调优化;最后,在Simulink与TruckSim联合仿真的平台上进行了4种工况的对比试验,研究结果表明:文中所提出的轨迹跟踪与底盘稳定性协调控制方法,在各种路面附着和行驶工况下,相比于现有控制方法在轨迹跟踪准确性和行驶稳定性方面都有明显的提升,具有一定的工程应用价值。

摘要：简介SUPER位于中国某省X市,是一个智能科技与历史文化并存的城市。这里依山傍水,曾是楚国重镇。这里有丰富的自然资源,但垃圾处理问题及交通问题阻碍着城市的发展。在2020年,X市有很多垃圾,居民在没有进行分类的情况下随意扔垃圾是导致城市脏乱的主要原因。垃圾处理厂只能将未分类的垃圾直接焚烧或填埋。