The processing of cartographic data demands human involvement. Up-to-date algorithms try to automate a part of this process. The goal is to obtain a digital model, or additional information about shape and topology of input geometric objects. A topological skeleton is one of the most important tools in the branch of science called shape analysis. It represents topological and geometrical characteristics of input data. Its plot depends on using algorithms such as medial axis, skeletonization, erosion, thinning, area collapse and many others. Area collapse, also known as dimension change, replaces input data with lower-dimensional geometric objects like, for example, a polygon with a polygonal chain, a line segment with a point. The goal of this paper is to introduce a new algorithm for the automatic calculation of polygonal chains representing a 2D polygon. The output is entirely contained within the area of the input polygon, and it has a linear plot without branches. The computational process is automatic and repeatable. The requirements of input data are discussed. The author analyzes results based on the method of computing ends of output polygonal chains. Additional methods to improve results are explored. The algorithm was tested on real-world cartographic data received from BDOT/GESUT databases, and on point clouds from laser scanning. An implementation for computing hatching of embankment is described.
In this paper were conducted virtual tests to assess the impact of geometry changes on the response of metallic hexagonal honeycomb structures to applied loadings. The lateral compressive stress state was taken into consideration. The material properties used to build numerical models were assessed in laboratory tests of aluminium alloy 7075. The modelling at meso-scale level allow to comprehensive study of honeycomb internal structure. The changes of honeycomb geometry elements such as: fillets radius of the cell edges in the vicinity of hexagonal vertexes, wall thickness were considered. The computations were conducted by using finite element method with application of the ABAQUS finite element method environment. Elaborated numerical models allowed to demonstrate sensitivity of honeycomb structures damage process response to geometry element changes. They are a proper tools to perform optimization of the honeycomb structures. They will be also helpful in designing process of modern constructions build up of the considered composite constituents in various branches of industry. Moreover, the obtained results can be used as a guide for engineers. Conducted virtual tests lead to conclusion that simplification of the models of internal honeycomb structure which have become commonplace among both engineers and scientist can lead to inaccurate results.