Combination Of Mesh Refinement Research Articles

PROCEDURE FOR RECONSTRUCTION OF GAJETA HULL FORM USING PHOTOGRAMMETRIC MEASUREMENT METHOD

Traditional shipbuilding is an important part of Croatian cultural and national heritage that needs to be preserved. This refers to the importance of documenting and transmitting knowledge and skills and preserving the authenticity of the shapes, dimensions, materials and technology of building traditional boats. One of the problems that arises in the revitalization and reconstruction of traditional boats is the lack of documentation, so it is necessary to make line drawings and show the details of traditional construction solutions. The paper presents a procedure for reconstruction of the hull form of a traditional boat using the photogrammetric method. In the preparation phase of the procedure the activities of recording and analysis of photographs are necessary. The SfM approach was used in this phase. The result of the processed data with this method is a cloud of measured points. These points were used in the next step of the procedure for the creation of the preliminary mesh to describe the hull form. In the final phase of the procedure the exact 3D hull model was created using combination of mesh refinement in specialized software and measurement updates from the boatbuilders. The advantages in use of photogrammetric measurement method, in combination with the SfM method for photo analysis, for the reconstruction of the hull form of a traditional boat are highlighted in the conclusion.

SOLUTION OF THE TWO‐DIMENSIONAL NEUTRON TRANSPORT EQUATION BY A HIERARCHICAL FINITE ELEMENT METHOD

Following the results obtained by Marchuk et al. concerning the variational principles for kinetic equations, a hierarchical finite element method is proposed for solving the two‐dimensional neutron transport equation. The combination of mesh refinement with additional basis functions leads to an accurate and efficient iterative solution of the resulting block linear systems. Numerical results are provided to illustrate the efficiency of the method.

Implementation of a finite element software system with H and P extension capabilities

Some aspects of implementation of an advanced finite element software system is described. The software system, called PROBE, permits assessment of the quality of finite element solutions through p-extension, (i.e. increase in the polynomial degree of elements), and permits the user to control of the quality of finite element solution through a combination of mesh refinement and p-extension. An example, showing how feedback information generated by p-extension can be used for controlling the quality of the finite element solution, is presented