Reconstruction Layout Optimization of Multivariety and Small Batch Workshop in Aerospace Industry.

To cope with the problems of frequent mold changes, long production cycles and serious logistics crossings in workshop of aerospace enterprise. First, a manufacturing cell layout planning method based on the feature bit code domain method and K-Means++ is proposed to realize the accurate division of manufacturing cells. Then, a multiobjective optimization method of dynamic reconstruction layout based on improved fruit fly optimization algorithm (IFOA) is proposed to solve the reconstruction layout optimization of the production workshop problem with the optimization objectives of logistics cost, reconstruction cost, loss cost, and cell integrated area. Finally, plant simulation software is applied to simulate the workshop layout before and after optimization. The simulation results show that the logistics cost of the workshop cell layout after optimization is reduced by 8.7%, the utilization rate of the workshop area is improved by 5.2%, and the value-added rate of products is increased by 6.6%, which verifies the effectiveness and feasibility of the proposed model and method.

1,4-Dimeth-oxy-2,5-bis-{2-[4-(trifluoro-meth-yl)phen-yl]ethyn-yl}benzene.

The asymmetric unit of the title compound, C(26)H(16)F(6)O(2), contains one half of the mol-ecule situated on an inversion centre. In the rod-like mol-ecule, the two terminal benzene rings form a dihedral angle of 71.9 (1)° with the central benzene ring. The trifluoro-methyl group is rotationally disordered over two orientations in a 0.53 (1):0.47 (1) ratio. The crystal packing exhibits no classical inter-molecular inter-actions.