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Nowadays, the society is paying more and more attention to the issues that plague the environment. There is a growing need for enterprises to design and manufacture environmentally friendly products, in order to take up the responsibility of sustainable development of the society. The entire product life cycle consists of design, manufacturing, usage and recycling phases. These phases involve various economic and environmental factors that affect the recyclability of products. Previous researchers mainly focused on the single phase of the product’s life cycle. Moreover, they did not take into account the dynamic change of the recyclable material’s cost. In this paper, a time-series forecasting methodology is proposed to evaluate the product’s recyclability at the product design phase. It considers various economic and environmental factors of different stages of the product’s life cycle. In addition, a time-series forecasting method is utilised for predicting the cost of the recycled material at the product’s end-of-life. To demonstrate the effectiveness of this methodology, a case study of a cylinder engine design was presented. The results showed that the proposed methodology was fully capable of providing decision support to the designers by accessing the recyclability of the product at the design phase. [ABSTRACT FROM AUTHOR]

Purpose - The purpose of this paper is to present a novel strategy used for acceleration of free-vibration analysis, in which the hierarchical matrices structure and Compute Unified Device Architecture (CUDA) platform is applied to improve the performance of the traditional dual reciprocity boundary element method (DRBEM). Design/methodology/approach - The DRBEM is applied in forming integral equation to reduce complexity. In the procedure of optimization computation, H-Matrices are introduced by applying adaptive cross-approximation method. At the same time, this paper proposes a high-efficiency parallel algorithm using CUDA and the counterpart of the serial effective algorithm in H-Matrices for inverse arithmetic operation. Findings - The analysis for free-vibration could achieve impressive time and space efficiency by introducing hierarchical matrices technique. Although the serial algorithm based on H-Matrices could obtain fair performance for complex inversion operation, the CUDA parallel algorithm would further double the efficiency. Without much loss in accuracy according to the examination of the numerical example, the relative error appeared in approximation process can be fixed by increasing degrees of freedoms or introducing certain amount of internal points. Originality/value - The paper proposes a novel effective strategy to improve computational efficiency and decrease memory consumption of free-vibration problems. H-Matrices structure and parallel operation based on CUDA are introduced in traditional DRBEM. [ABSTRACT FROM AUTHOR]

Measured data of a product can be incomplete because of the inaccessibility or invisibility of some portions of the product surface for measure tools in reverse engineering. Usually, the missed surface areas include some key form features of the product, which represent important design components. However, flat surfaces are often used to mend the incomplete form features in current reverse engineering systems. In this paper, an incomplete data repair method is presented using a deformable model under the constraints of given feature forms. The method ensures the accuracy of identifying the missed local areas by choosing a set of proper rules of mesh construction according to the density distribution of measured data, and fills them with an energy-based, deformable local mesh that is adaptively-formed using an iteration of the procedure of mesh subdivision, constraint satisfaction and finite element equation solving. [ABSTRACT FROM AUTHOR]

The one-dimensional velocity interferometer system for any reflector (VISAR) is widely used in inertial confinement fusion (ICF). Compressed ultrafast photography (CUP) is recently combined with VISAR to enable two-dimensional imaging, in which, the time-varied two-dimensional fringe images reconstruction from one image is a challenging problem. In this Letter, a new l 1 norm based sparse reconstruction approach is presented, to the best of our knowledge, in which: (1) fringe images are sparsely represented with a few coefficients over the discrete cosine transformation (DCT) basis; (2) the image reconstruction is formulated as an l 1 norm based sparse coefficients optimization problem; and (3) the two-step iterative shrinkage/threshold algorithm combined with a soft-thresholding operator is proposed to efficiently solve such a problem. Finally, the results show that, compared with the usual method, reconstructed fringe images with clear boundaries and good continuity are obtained. Additionally, the maximum relative error of the velocity is reduced from 14% to 8%, which is a reduction of approximately half.