arXiv subjects

Weining Zhu

Publications and source records attributed to Weining Zhu.

3 recordsLinked to original sources

arXiv2026

A unified cell-merge algorithm for generating diverse Voronoi diagrams and new tessellations based on spatial chromatic model

As a type of spatial tessellation model and an important spatial structure of computational geometry, Voronoi diagrams (VDs) are widely used in many fields. Due to differences in generation spaces, types of spatial entities, distance metrics, and relationships between entities and Voronoi regions, Voronoi diagrams vary into many types, such as the ordinary VD, VD on spheres, VD for linear entities, weighted VD, and ordered higher-order VD. These VDs also have their own generation algorithms. In this study, we propose a new cell-merge (CM) Voronoi generation algorithm based on the spatial chromatic model. The advantage of the CM algorithm is that it can quickly generate diverse VDs by retrieving and merging cells from a unified database, without requiring the development of specific algorithms for each VD. The CM Voronoi algorithm can be particularly applied in cases where a variety of Voronoi diagrams are frequently required for computation and analysis, such as in location-based spatial analysis. Furthermore, the proposed CM method can also generate some new types of spatial tessellations, such as competition intensity and couple-cell diagrams which are different from classical VDs.

cs.CG↗

arXiv2022

Statistical parameters for assessing environmental model performance related to sample size: Case study in ocean color remote sensing

Environmental model performances need to be assessed using some statistical parameters, such as mean absolute error (MAE) and root mean square error (RMSE). The advantages and disadvantages of these parameters are still in controversial. The purpose of this study is to introduce a statistical parameter, type A uncertainty (UA), into model performance evaluations. We particularly focus on the relations between sample sizes and three evaluation parameters, and tested a few ocean color remote sensing algorithms and datasets. The results indicate that RMSE, MAE and UA all vary with the sample size n but present different trends. Based on our tested results and theoretical analysis, we therefore conclude that UA is better than RMSE and MAE to express model uncertainty, because its downward trends indicate that the more samples we take, the less uncertainty we get. RMSE and MAE are good parameters for assessing model accuracy rather than uncertainty.

stat.AP↗

arXiv2016

Entity-oriented spatial coding and discrete topological spatial relations

Based on a newly proposed spatial data model - spatial chromatic model (SCM), we developed a spatial coding scheme, called full-coded ordinary arranged chromatic diagram (full-OACD). Full-OACD is a type of spatial tessellation, where space is partitioned into a number of subspaces such as cells, edges, and vertexes. These subspaces are called spatial particles and assigned with unique codes - chromatic codes. The generation, structures, computations, and properties of full-OACD are introduced and relations between chromatic codes and particle spatial topology are investigated, indicating that chromatic codes provide a potential useful and meaningful tool not only for spatial analysis in geographical information science, but also for other relevant disciplines such as discrete mathematics, topology, and computer science.

cs.CG↗