Showing 3 results for Mashayekhi
A. N. Mashayekhi and B. Arbabshiriani,
Volume 21, Issue 2 (1-2003)
Abstract
Knowledge is one of the most important organizations assets. To manage knowledge effectively, it is necessary to be able to measure knowledge. There are few methods for knowledge measurement with certain limitations. One important weakness of current methods is their insufficient attention to definition, dimensions and attributes of knowledge.
In this paper, we propose a new method for measuring the level of an engineering organizations knowledge. According to our proposed method, the level of an organizations knowledge is a function of both knowledge hierarchy and knowledge dimensions. The method is applied to an engineering organization to measure the level of knowledge at two different times and the results are presented.
Keywords: Knowledge, Knowledge management, Knowledge measurement, Knowledge hierarchy, Knowledge dimensions
M. Mashayekhi, S. Ziaei-Rad, and J. Parvizian,
Volume 25, Issue 2 (1-2007)
Abstract
The continuum mechanic simulation of micro-structural damage process is important in the study of ductile fracture mechanics. In this paper, the continuum damage mechanics model formulation proposed by Lematire has been validated against ductile damage evolution experimentally measured in A533B-C1 steel under stress triaxiality conditions. First, a
procedure to identify the model parameters from test was defined. Then, the finite element model was used to simulate the experiment carried out on a notched flat rectangular bar. Good agreement was observed between the experimental results and finite element predictions. Next, the identified parameters on A533B-C1 steel were used to simulate the results from a conventional tensile test by finite element method. The specimen was prepared according to ASTM E08 standard. The stresses at necking stage and ultimate load calculated by the damage based method were compared with those obtained from the test. The comparisons indicate a good agreement between the simulated and the experimental results.
A. H . Mehdizadeh, M. Mashayekhi, M. Kadkhodaei,
Volume 35, Issue 1 (9-2016)
Abstract
This article predicts lifetime of high cycle fatigue loading using Chaboche-Lemaitre damage model. The Chaboche-Lemaitre damage model takes into account mean stress effect as well as compressive stresses effect, making crack to close. In the this paper, a numerical algorithm is offered to integrate this model implicitly and the obtained algorithm is implemented as a user material subroutine of the ABAQUS finite element software. To reduce computation time, Jump-in-Cycles procedure is used based on fatigue loading simulation. To verify the proposed algorithm, a V-notched specimen is chosen under a fatigue loading with different stress ratios, and its lifetime is compared with experiments. Next, an aviation industry part, main rotor spindle of an aircraft blades, subjected to a variable fatigue loading is analysed.
