02414nas|a2200253 i 450000500170000000800410001703500150005810000240007324501000009726000520019730000150024949000270026450001360029150200580042752013090048565000230179465000360181770000400185370000510189370000450194471000470198981000590203685600650209520260817161531.0010713s2001    th  uzm rtt  00|  a1eng d  a.b118294970 aPamuda Pudjisuryadi13aAn adaptive technique for 2d elastostatic analysis by the meshless local Petrov-Galerkin method  aBangkok :bAsian Institute of Technology,c2001  a114 leaves1 aThesis ;vno. ST-01-08  aA thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Civil Engineering   aThesis (M.Eng.) - Asian Institute of Technology, 2001  aA meshless local Petrov-Galerkin method that employs polygonal nodal sub-domains constructed from several triangular patches rather than the typically used circular sub-domains is presented. Moving least-squares approximation is used as the trial functions while linear Lagrange interpolation functions are used as the test functions. In the MLPG method, redescritization of the problem domain is relatively simple as compared to the finite element methods, and therefore an adaptive technique to improve the accuracy of approximate solutions with a minimum of extra computational cost is developed. The adaptive MLPG method, which considers with local error assessment and placement of additional nodes, is the focus of this study. Two refinement indicators, a local L2-norm of displacement error and an approximate effective stress gradient are introduced. Additional nodes are placed at the middle of each of the edges of the patch which exceeds the prescribed error level. A method to vary the domain of influence (DOI) adaptively is also proposed in this study. Numerical examples show that the adaptive MLPG method performs well. The combination of the effective stress gradient error indicator and the variable DOI was found to provide exceptional accuracy at a highly reduced computational cost. 10aNumerical analysis10aDifferential equations, Partial1 aBarry, William Joseph,eChairperson0 aWorsak Kanok-Nukulchai,eExamination Committee1 aPing,  Zhu Hong, eExamination Committee2 aGovernment of Austria, eScholarship Donor2 aAsian Institute of Technology.tThesis ;vno. ST-01-08  3Full-Textuhttp://203.159.5.9/ait-thesis/detail.php?q=B09463