Multi-Objective Image Optimization of Product Appearance Based on Improved NSGA-II

A second-generation fast Non-dominated Sorting Genetic Algorithm product shape multi-objective imagery optimization model based on degradation(DNSGA-II)strategy is proposed to make the product appearance optimization scheme meet the complex emotional needs of users for the product.First,the semantic differential method and K-Means cluster analysis are applied to extract the multi-objective imagery of users;then,the product multidimensional scale analysis is applied to classify the research objects,and again the reference samples are screened by the semantic differentialmethod,and the samples are parametrized in two dimensions by using elliptic Fourier analysis;finally,the fuzzy dynamic evaluation function is used as the objective function of the algorithm,and the coordinates of key points of product contours Finally,with the fuzzy dynamic evaluation function as the objective function of the algorithm and the coordinates of key points of the product profile as the decision variables,the optimal product profile solution set is solved by DNSGA-II.The validity of the model is verified by taking the optimization of the shape scheme of the hospital connection site as an example.For comparison with DNSGA-II,other multi-objective optimization algorithms are also presented.To evaluate the performance of each algorithm,the performance evaluation index values of the five multi-objective optimization algorithms are calculated in this paper.The results show that DNSGA-II is superior in improving individual diversity and has better overall performance.

Fabrication of a three-dimensional micro/nanocarbon structure with sub-10 nm carbon fiber arrays based on the nanoforming and pyrolysis of polyacrylonitrile-based jet fibers

To produce a three-dimensional micro/nanocarbon structure,a manufacturing design technique for sub-10 nm carbon fiber arrays on three-dimensional carbon micropillars has been developed;the method involves initiating electrostatic jetting,forming submicron-to-nanoscale PAN-based fibers,and maximizing the shrinkage from polyacrylonitrile(PAN)-based fibers to carbon fibers.Nanoforming and nanodepositing methods for polyacrylonitrilebased jet fibers as precursors of carbon fibers are proposed for the processing design of electrostatic jet initiation and for the forming design of submicron-to-nanoscale PAN-based fibers by establishing and analyzing mathematical models that include the diameter and tensile stress values of jet fibers and the electric field intensity values on the surfaces of carbon micropillars.In accordance with these methods,an array of jet fibers with diameters of~80 nm is experimentally formed based on the thinning of the electrospinning fluid on top of a dispensing needle,the poking of drum into an electrospinning droplet,and the controlling of the needle–drum distance.When converting thin PANbased jet fibers to carbon fibers,a pyrolysis method consisting of the suspension of jet nanofibers between carbon micropillars,the bond between the fibers and the surface of the carbon micropillar,and the control of micropillar spacing,stabilization temperature,and carbonation rate is presented to maximize the shrinkage from PAN-based fibers to carbon fibers and to form sub-10 nm carbon fiber arrays between three-dimensional carbon micropillars.The manufacturing design of a three-dimensional micro/nanocarbon structure can produce thin PAN-based jet nanofibers and nanofiber arrays aligned on micropillar surfaces,obtain shrinkage levels reaching 96%and incorporate sub-10 nm carbon fibers into three-dimensional carbon micropillars;these actions provide new research opportunities for correlated three-dimensional micro/nanocarbon structures that have not previously been technically possible.