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关键词： Intelligent controller   Path navigation   A* search with fuzzy logic   Best path   MATLAB  

摘要： In this paper, an intelligent controller is introduced for effective path navigation and control of single and multiple autonomous vehicles in unknown environments with obstacle avoidance mechanisms. Path navigation of multiple autonomous vehicles is necessary to solve problems in different types of traffic, industrial, military, and surveying applications. The controller uses an A* search with fuzzy logic to determine the best path to the goal. A navigation strategy has been established to maintain cooperation between autonomous vehicles in an environment with static and dynamic obstacles. Autonomous vehicles achieve multiple goals in coordination with each other. The proposed controller was tested in a MATLAB simulator. The path lengths and elapsed times of the autonomous vehicles with the proposed controller are calculated and compared with those of other existing approaches. The proposed controller improves the travel distance by approximately 18.24%.

关键词： 建筑工程   钢结构   工程质量   安全控制   应用措施  

摘要： 国民经济水平的不断提高推动了建筑行业的蓬勃发展,建筑钢结构工程规模及数量随之增加.较长的施工周期、较多的施工内容、较广的影响因素等,提高工程项目建设过程中出现质量隐患的可能性,这就要求施工企业加强质量与安全控制,特别是对于特殊部位,以提高工程质量,延长使用寿命.通过对建筑钢结构特点进行分析,探讨了建筑钢结构工程质量与安全控制现状,并提出了相应的优化措施,以期更好地推动我国建筑行业高质量发展.

关键词： 建筑工程   意义   造价   全过程管控  

摘要： 建设单位在工程项目中的成本投入受造价管控水平直接影响,这一管理水平与建筑企业的经济效益及利润紧密相连.在激烈的市场竞争中,如何有效控制工程造价,成为建筑行业关注的焦点.建筑工程造价的全过程管控,即从投资决策到竣工结算的各个环节都进行严格的管控,是实现这一目标的重要手段.因此,基于建筑工程全过程造价管控的意义,深入探究了建筑工程中全过程造价管控要点,以期能为相关人员提供参考.

关键词： 工业污水处理厂   化工废水   水解酸化   臭氧催化氧化  

摘要： 为解决化工园区综合工业污水处理问题,以南通经济技术开发区化工园区污水处理厂为例,对工业废水水质特点及处理设施效能进行研究,提出"预处理(分质处理)+二级处理(水解酸化+氧化沟+混凝沉淀)+深度处理(高级催化氧化+磁混凝高效沉淀池+反硝化滤池)+次氯酸钠消毒"的工艺路线,探讨了化工园区综合工业污水处理厂的部分设计要点,为国内类似化工园区的工业污水厂建设提供借鉴思路和案例参考.

关键词： Magnetic levitation vehicles  

摘要： Rich-nickel layered ternary NCM811 has been widely used in the field of electric vehicles ascribed to its high theoretical specific capacity. However, poor cycling stability and rate-performance hindered its further development. Herein, different amounts of nitrogen-doped carbon were wrapped on the surface of NCM811 via a facile rheological phase method by regulating the amount of dopamine hydrochloride. The effects of the coating amounts on the structure and electrochemical performance are investigated. The DFT calculation, XRD, SEM and XPS reveal that an appropriate amount of nitrogen-doped carbon coating could uniformly form a protective layer on the NCM811 surface and the introduced N could anchor Ni atoms to inhibit the Li+/Ni2+ mixing, but excessive amount would reduce Ni3+ to Ni2+ so as to conversely aggravate Li+/Ni2+ mixing. Among the samples, the NCM811-CN0.75 sample exhibits the most excellent electrochemical performance, delivering a high-rate capacity of 151.6 mA·h/g at 10C, and long-term cyclability with 82.2% capacity retention after 300 cycles at 5C, exhibiting remarkable rate-performance and cyclability.

关键词： 构造地质   薄煤层   构造定量评价   构造曲率   趋势面分析   煤厚变异系数   稳定性   精准开采  

摘要： 薄煤层条件下的煤炭开采对精确掌握煤厚与构造的空间变化规律提出了更高要求。陕西延安黄陵矿区北部发育薄煤层，对其构造发育特点与煤厚空间变化规律认识不清，限制了煤炭高效开采与智能化矿井建设。笔者以延安芦村二号煤矿主采的2号煤层为研究对象，基于煤层底板标高数据，开展趋势面分析与构造曲率分析，揭示构造展布与发育特点;基于网格剖分法计算了775个网格节点的煤厚变异系数，揭示煤层厚度及其稳定性变化规律，克服了传统煤厚变异系数单一评价值对揭示煤厚稳定性空间变化的不足。结果显示，芦村二号煤矿2号煤层属于较稳定煤层，整体呈一走向NE、倾向NW的单斜构造，在此背景下，叠加了轴向为NW的次级波状起伏。新识别并圈定了3处典型构造，分别为：煤矿东北部发育一局部凹陷，中北部发育一局部凸起，煤矿南部发育一个呈NW—SE向展布的马鞍状构造。在马鞍状构造北部叠加了勘探与采掘期间发现的若干断层，使得煤矿南部构造相对复杂。煤厚变异系数介于0.16%～15.24%，平均为1.98%，呈现从北向南逐渐增加的趋势，在西南部12-7和12-8号钻孔附近达到最大值。在可采范围内，煤层厚度稳定性由NE向SW逐步变差，马鞍状构造与煤厚变异系数高值区高度吻合。基于煤厚及煤厚变异系数分级，识别出6类煤厚及稳定性组合方案，实现了煤厚及稳定性的平面分区评价，揭示可采范围内东部的开采条件好于西部，西南部最差，源于马鞍状构造加剧了煤厚变化。研究成果可为薄煤层安全、高效、精准开采提供地质保障。

关键词： 移动机器人   多传感器融合   同步定位与地图构建   误差状态卡尔曼滤波   闭环检测  

摘要： 同步定位与地图构建(SLAM)技术是移动机器人智能导航的基础。该文针对单一传感器SLAM技术存在的问题，提出一种基于激光雷达多层迭代最近点(MICP)点云匹配闭环检测的误差状态卡尔曼滤波(ESKF)多传感器紧耦合2D-SLAM算法。在完成视觉与激光雷达多模态数据的时空同步后，建立了里程计误差模型以及激光雷达与机器视觉点云匹配误差模型，并将其应用于误差状态卡尔曼滤波进行多模态数据融合，以提高SLAM的准确性和实时性。在公共数据集KITTI下进行的Gazebo环境仿真结果表明，该所提算法能够完整还原单一激光2D-SLAM无法获取到的环境障碍物信息，并能显著提高机器人轨迹估计和相对位姿估计精度。最后，采用Turtlebot2机器人在复杂实际大场景下进行了SLAM实验验证，结果表明所提多模态融合SLAM方法可以完整复原环境信息，实现实时的高精度2D地图构建。

关键词： Cracks  

摘要： In existing studies, most slope stability analyses concentrate on conditions with constant temperature, assuming the slope is intact, and employ the Mohr-Coulomb (M-C) failure criterion for saturated soil to characterize the strength of the backfill. However, the actual working temperature of slopes varies, and natural phenomena such as rainfall and groundwater infiltration commonly result in unsaturated soil conditions, with cracks typically present in cohesive slopes. This study introduces a novel approach for assessing the stability of unsaturated soil stepped slopes under varying temperatures, incorporating the effects of open and vertical cracks. Utilizing the kinematic approach and gravity increase method, we developed a three-dimensional (3D) rotational wedge failure mechanism to simulate slope collapse, enhancing the traditional two-dimensional analyses. We integrated temperature-dependent functions and nonlinear shear strength equations to evaluate the impact of temperature on four typical unsaturated soil types. A particle swarm optimization algorithm was employed to calculate the safety factor, ensuring our method’s accuracy by comparing it with existing studies. The results indicate that considering 3D effects yields a higher safety factor, while cracks reduce slope stability. Each unsaturated soil exhibits a distinctive temperature response curve, highlighting the importance of understanding soil types in the design phase.