Research On 3D Modelling Theory And Technology Of Global Ocean Body

From the 20 th century,the marine science has obtained a quick development,and people gradually realize that the ocean plays a crucial role in regulating the global environment and maintaining the sustainable development of human society.Since the 1990 s,researches focused on both the offshore and inshore have become the international oceanographic research trends,and this has showed some global,holistic,and systemic characteristics.The body of the global marine water is the basis of a global perspective for the study of marine environment monitoring in ocean currents,weather forecasting,disaster prevention and mitigation,environmental governance,and polar expedition.For the marine water bodies worldwide,three-dimensional polar ice modeling,simulation,and analysis have become several research hotspots.In this thesis,the author focuses on the requirement of three-dimensional modeling of the global ocean water,polar ice,and the visualization,and the work is performed in terms of three-dimensional geometric model of the global ocean water grid model,storage model,data organization.Specifically,the main results are as follows:(1)Through analyzing the structure of space-based global marine water body,the author proposes the space for elements of geometry,and the spatial dimension elements of the space which involves the following relationship: the space factor equal elements of the border on behalf of its geometry in the space dimension of its space;dimensional space when the number of elements below it in the space dimension of space.This does not represent elements of the geometry of the boundary elements,but needs to increase the number of low-dimensional data points,or type a value line(also called skeleton)in order to completely describe the spatial geometry of the elements.According to above statements,the proposed "Being on the lower surface of the suture in the ocean water coastline constitute geometric border" concept model of the global ocean water macroscopic geometry.Among them,the ocean is approximately spherical marine geoids or measured on the surface of the global ocean surface water bodies,rugged terrain surface of the lower surface of the seabed,while the upper and lower surfaces stitched on the coastline composition.Global ocean water to build three-dimensional geometric model of the global ocean water space grid,and building a global data organization and management of the marine environment should be supported by the basic theory.(2)The proposed global ocean water diamond prism mesh models includes surface mesh,mesh radial surface with radial sectional asynchronous parts.Firstly,according to the spherical octahedron Quaternary Triangular Mesh(QTM)with quadtree structure,the surface of the diamond mesh method is proposed based on the latitude circle interpolation method,that can reduce the surface diamond grid cell calculated from the level of consumption of subdivision process.In addition,the ellipsoid and spheres are analyzed with maximum and minimum area ratio diamond grid cell,the maximum and minimum side length ratio is based on the discovery of the index ellipsoid geometry changes and positive sphere converge,and therefore the difference is small.Then,the designed division of radial bisection method is to achieve the global ocean water at different depths of space subdivision.Thirdly,taking into account of the marine environmental data surface resolution and the larger different radial resolution proposed subdivision surface with radial-step approach to enhance the adaptability of the three-dimensional mesh.With this surface diamond mesh which bisecting the radial division,a rule-based Octree diamond prism-dimensional mesh model is formed.(3)For the global marine environment of multi-source,multi-resolution,features massive data and application requirements,a diamond prism grid storage solutions is designed,and in detail the author discusses the image,elevation,water field data(temperature,salinity,density,etc.)of the conversion process;the proposed construction of a sparse octree indexing and retrieval algorithms and implementation based on relational databases.(4)For the water treatment field data in three-dimensional grid interpolation problem,a prism tetrahedral diamond segments based on body function interpolation algorithm is proposed.Firstly,the design of the rhombic prism vertex grid cell sorting method is proposed as a subdivision algorithm diamond prism tetrahedral grid cell.Then,the mathematical model and body function fitting method are both analyzed,and proposed the tetrahedral body function interpolation algorithm.(5)Finally,a three-dimensional modeling of global ocean waters and visualization prototype system is developed,and it realized the global seabed depth,sea surface height,sea data field and other basic environmental and attribute field data unified organization and management,constructed including the global body of water ice at the poles body,the global water land,ice three-dimensional model,three-dimensional analysis of the evolution of the polar sea ice,dense seawater temperature and salinity data visualization.Some typical tasks,such as China ocean waters surrounding data modeling and organization,have been applied to verify the diamond prism-based three-dimensional the effectiveness of the grid global ocean water or ice and three-dimensional geometric model attribute field data organization model for the global ocean water or ice environmental research provides new tools and methods.