Geographic visualisation systems require methods for efficient data access. Retrieval of geographic data from large databases, of tens to thousands of Gbytes, needs optimisation using spatial indexing mechanisms. This paper describes how the indexing mechanism based on Ellipsoidal Quadtrees, EQT, can be implemented in software, e.g. for real-time or Internet visualisation. EQT fulfils the so-ca...

The current paper primarily aims to suggest a mathematical model for the shape-dependent term of Khan- Liu (KL) Yield/ fracture criterion as a function of Plastic Strain for DP590 steel alloy. The shape-dependent term in the mention criterion can generalize the application of this criterion in order to predict the behavior of other materials. Plane stress case and the first quarter of the stres...

natural sites with spiritual values are parts of land or sea that play key role in conserving biodiversity and cultural identity. the aim of this study is prioritizing protected zones with spiritual values. in the first step for this survey, based on literature review and according to multi criteria assessment, convenient conservation criteria were compiled, then for each of criterion, indices ...

For any wire-grid model, a fundamental question is the choice of the optimum wire radius and grid spacing. The most widely used criterion to fix the wire size is the so-called same-area rule [2], coming from empirical observation: the total surface area of the wires has to be equal to the surface area of the object being modelled. However, just few authors have investigated the validity of this...