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New passive double L-shaped micromixers have been investigated based on the split and recombination flow. Numerical study on micromixers was performed in the Reynolds number range of 50 to 200. The three-dimensional Navier-Stokes equations have been used to analyze flow and mixing behavior. Two different configurations from the positioning of L units have been investigated and two solutions have been proposed to improve the mixing index. If two L units are same shaped, aligned on one plate (design 1), the mixing index is low due to inappropriate split and recombination. The placement of two L units of the same shape on a two-plane parallel and non-aligned (design 2) improve the mixing index and increase to over 95% in Reynolds numbers of 100, 150, and 200. The orthogonal solution to the inputs did not affect the pressure drop and only in design 1, the mixing index could exceed 95% in all Reynolds numbers. Unbalanced micromixer solution improves mixing index by increasing pressure drop. The effect of geometric parameter of asymetric width ratio in both designs was studied and design 1 in asymetric width ratio 2.5 and design 2 in asymetric width ratio 2 and 2.5 have been completely mixed in all Reynolds numbers. Also, the performance of proposed micromixers was better than L-shaped micromixer due to the split and recombination mechanism. In addition, the mixing index was higher in porposed micromixers compared to the split and recombined micromixers of previous researchers due to the use of L-shaped units.
 

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Construction projects are one of the most complex types of projects due to unpredictability process, operation and resource constraints. This leads to crucial role of project manager for the success of construction projects. Therefore, construction manager’s project selection is a significant issue. On the other hand, systematic selection of the project manager is necessary. In the past, systematic selection has not been considered and further personal and expert’s opinions have been toward project manager selection. In order fill this void, a research was conducted to select the construction project manager based on the competence model. Initially, by comparing standards of project management competence, project management standard of Australia was selected as the most appropriate model. Then, by distributing a questionnaire to experts of the decision-making team using the SWARA method, the criteria and the sub criteria were weighted. Weighting results showed that sub-criteria of leadership ability, ability to conduct and ability to manage environmental change were identified as the most important sub-criteria. Then, using the WASPAS method, project management alternatives were ranked.