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The product concept evaluation plays a very important role in product development. It can be considered as multi-criteria decision making (MCDM) problem. In a MCDM problem, a decision maker has to choose the best alternative that satisfies the evaluation criteria among a set of candidate solutions. This paper introduces a compromise MCDM evaluation model which combines fuzzy DEMATEL and VIKOR methods. The criteria weights are determined based on separate cause-effect assessment of a group of experts using the fuzzy DEMATEL approach. The resulting criteria weights are applied to the decision analysis where the fuzzy VIKOR approach is adopted which determines a compromise solution by using utility weight.

Scheduling for the flexible job shop is very important in fields of production management. To solve the multi–objective optimization in flexible job shop scheduling problem (FJSP), the FJSP multi-objective optimization model is constructed. The cost, quality and time are taken as the optimization objectives. An improved strength Pareto evolutionary algorithm (SPEA2+) is put forward to optimize the multi-objective optimization model parallelly. The algorithm uses a new model of a Multi-objective genetic algorithm that includes more effective crossover and could obtain diverse solutions in the objective and variable spaces to archive the Pareto optimal sets for FJSP multi-objective optimization. Then an approach based on fuzzy set theory was developed to extract one of the Pareto-optimal solutions as the best compromise one. The optimization results were compared with those obtained by NSGA-II and POS. At last, an instance of flexible job shop scheduling problem in automotive industry is given to illustrate that the proposed method can solve the multi-objective FJSP effectively.

Multiscale visualization approaches are proposed to efficiently assist designers not familiar with statistical mathematics in determining the optimal process parameter schemes for achieving desired part quality in injection molding, based on which the parameters’ relative importance to part quality and their influence on either single quality index or comprehensive part quality can be visually described by the map of the sum of squared deviations, response surface diagram and distribution map of comprehensive part quality. The proposed visualization approaches are universal for analyzing the effects of process parameters on the quality of any injection-molded plastic parts although the mobile phone cover is utilized as an example in the presentation of our work.

A theorem regarding the termination criterion for subdivision of triangular Bezier patch is presented with detailed proof. As the number of times for subdividing a triangular Bezier patch can be a determined prior, according to the given tolerance, the subdividing process can be conduced consecutively without checking for linearity after each subdivision. The theorem has potentials in various CAD/CAM applications.