Building reconstruction is one of the most difficult and important 3D modelling problems for urban environment. In this paper, we develop an approach using minimum number of basic geometric elements to reconstruct the buildings. The basic element is a number of unstructured 3D points representing the topological identity of a building roof. Such point primitives can be measured by human or comp...

This paper presents a model-based approach for 3-D building reconstruction unstructured distinct points. The data structure of a building is an unstructured roof point cloud digitized by operators. Constructive Solid Geometry (CSG) model is applied in our approach for a complex roof which can be decomposed into three types of primitive models. The primitive model is represented as a tree. The l...

Let be a commutative ring with 1 and left unitary . In this paper, the generalizations for notions of compressible module retractable are given. An is termed to semi-essentially if can embedded in every non-zero semi-essential submodules. module, submodule an Some their advantages characterizations examples We also study relation between these classes some other modules.

This paper compares the paradigms of LiDAR and aerophotogrammetry in the context of building extraction and briefly discusses a photogrammetric strategy for refining building roof polyhedrons previously extracted from LiDAR data. In general, empirical and theoretical studies have confirmed that LiDAR methodologies are more suitable in extracting planar roof faces and ridges of the roof, whereas...

The soil water retention curve (SWRC) relates moisture to energy (matrix potential). calculation of the volumetrichumidity considers sample volume. In retractable soils, this volume varies according drying or wetting soil, which can result in errors calculated moisture. objective study is quantify variation soils and elaborate SWRC via traditional method, does not consider retraction, a second ...

This paper presents a data-driven method for automatic building reconstruction from raw airborne laser scanner data. The method utilises a TIN-structure that is calculated into the point cloud. The parameters of every TIN-mesh are mapped into a 3D trianglemesh parameter space, which is then analysed using a cluster analysis technique. By analysing the clusters, significant roof planes are deriv...

INTRODUCTION The medial maxillary sinus roof is a ridge formed by the superior margin of the maxillary sinus antrostomy. The posterior wall of the maxillary sinus is always included in operative fields. OBJECTIVE To perform a radiologic study assessing the utility of the medial maxillary sinus roof and the posterior wall of the maxillary sinus as fixed landmarks for providing a safe route of ...