基于对地理信息系统(geographic information system,GIS)图形美观技术的需求,将基于泰森多边形的缓冲区骨架线提取技术应用于配电网GIS图中,提出基于泰森多边形的配电网GIS图美化算法。首先通过缓冲处理把若干条距离相近的馈线合并为...基于对地理信息系统(geographic information system,GIS)图形美观技术的需求,将基于泰森多边形的缓冲区骨架线提取技术应用于配电网GIS图中,提出基于泰森多边形的配电网GIS图美化算法。首先通过缓冲处理把若干条距离相近的馈线合并为一个整体,得到包络缓冲区;再利用泰森多边形,得到该缓冲区的中心线和每段“廊道”所包含的具体馈线段;然后等间隔排列此段廊道内的所有馈线段;再采用“前推后代”法得到整条馈线上、下级线段之间的连接关系;最后将相关配电设备和开关设备接入其所属馈线段,即完成整条馈线的美化。该算法解决了配电网GIS单线图美化的技术难题,使其经程序自动化处理后即可用于配电网地理接线图的规划编制工作。展开更多
针对现有任意多边形骨架线提取方法存在的算法设计繁琐、代码实现复杂、实现成本高和周期长的缺点,提出一种基于地理信息系统(geographic information system,GIS)空间分析的任意多边形骨架线自动提取方法。首先,以电子地图为数据源,在E...针对现有任意多边形骨架线提取方法存在的算法设计繁琐、代码实现复杂、实现成本高和周期长的缺点,提出一种基于地理信息系统(geographic information system,GIS)空间分析的任意多边形骨架线自动提取方法。首先,以电子地图为数据源,在ENVI和Arc GIS平台的支持下,通过调用Arc Toolbox工具箱中的ENVI分类模型工具提取出空间对象的多边形矢量边界,并对其进行预处理;其次,综合运用数据处理、空间分析和文件转换工具提取其骨架结点,并对其进行后处理;再次,采用Python面向对象编程语言结合Arc Py站点包,通过编写脚本程序自动提取其骨架线;然后,进一步利用ModelBuilder工具,通过构建模型实现骨架线的自动提取;最后,将该方法分别应用于电子地图道路和建筑物多边形骨架线的提取。实验过程及其结果表明该方法具有一定有效性、实用性和可操作性。展开更多
Inspired by the safe landing of a cat falling from a high altitude,a bio-inspired polygonal skeleton(BIPS) structure is proposed,and its nonlinear characteristics are systematically studied to explore its potential ap...Inspired by the safe landing of a cat falling from a high altitude,a bio-inspired polygonal skeleton(BIPS) structure is proposed,and its nonlinear characteristics are systematically studied to explore its potential application in the suppression of vibration. The polygon is formed by the skeleton structure of the cat’s entire body and the ground. The BIPS system consists of two symmetrical bionic legs with three robs(as skeleton) and four horizontal springs(as muscle). Two bionic legs are connected through the bearing platform(as spine),which could adjust the distance between the two bionic legs. A theoretical model is developed to characterize its stiffness nonlinearity through geometrical and mechanical analysis. Parameter analysis reveals that the BIPS structure has diverse stiffness,including nonlinear positive stiffness and negative stiffness. By imitating adjustment of leg posture and telescopic function of the spine(control the distance between legs),these flexible stiffness properties can be adjusted by structure parameters. In addition,the load capacity and working range can also be designed by the length of the bars,the initial angle,the mounting position,and the spring stiffness. The experimental setup is established,and the vibration isolation performance under various excitation is tested. The experimental results verify the accuracy of the dynamic model and also show that the proposed BIPS structure can suppress the vibration effectively under a variety of excitations. These peculiarities may provide potential possibility of an innovative approach to passive vibration control and isolation.展开更多
文摘基于对地理信息系统(geographic information system,GIS)图形美观技术的需求,将基于泰森多边形的缓冲区骨架线提取技术应用于配电网GIS图中,提出基于泰森多边形的配电网GIS图美化算法。首先通过缓冲处理把若干条距离相近的馈线合并为一个整体,得到包络缓冲区;再利用泰森多边形,得到该缓冲区的中心线和每段“廊道”所包含的具体馈线段;然后等间隔排列此段廊道内的所有馈线段;再采用“前推后代”法得到整条馈线上、下级线段之间的连接关系;最后将相关配电设备和开关设备接入其所属馈线段,即完成整条馈线的美化。该算法解决了配电网GIS单线图美化的技术难题,使其经程序自动化处理后即可用于配电网地理接线图的规划编制工作。
基金This work was supported by the National Science Fund for Distinguished Young Scholars(Grant No.11625208)the Innovation Program of Shanghai Municipal Education Commission(Grant No.2019-01-07-00-02-E00030)the Program of Shanghai Academic/Technology Research Leader(Grant No.19XD1421600)。
文摘Inspired by the safe landing of a cat falling from a high altitude,a bio-inspired polygonal skeleton(BIPS) structure is proposed,and its nonlinear characteristics are systematically studied to explore its potential application in the suppression of vibration. The polygon is formed by the skeleton structure of the cat’s entire body and the ground. The BIPS system consists of two symmetrical bionic legs with three robs(as skeleton) and four horizontal springs(as muscle). Two bionic legs are connected through the bearing platform(as spine),which could adjust the distance between the two bionic legs. A theoretical model is developed to characterize its stiffness nonlinearity through geometrical and mechanical analysis. Parameter analysis reveals that the BIPS structure has diverse stiffness,including nonlinear positive stiffness and negative stiffness. By imitating adjustment of leg posture and telescopic function of the spine(control the distance between legs),these flexible stiffness properties can be adjusted by structure parameters. In addition,the load capacity and working range can also be designed by the length of the bars,the initial angle,the mounting position,and the spring stiffness. The experimental setup is established,and the vibration isolation performance under various excitation is tested. The experimental results verify the accuracy of the dynamic model and also show that the proposed BIPS structure can suppress the vibration effectively under a variety of excitations. These peculiarities may provide potential possibility of an innovative approach to passive vibration control and isolation.
