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Profile measurement with boundary information plays a vital role in the detection of quality in the assembly of aviation parts. The purpose of this paper is to improve the evaluation accuracy of the aerodynamic shapes of airplanes, the profiles of large-sized parts need to be measured accurately.

In this paper, an accurate profile measurement method based on boundary reference points is proposed for the industrial stereo-vision system. Based on the boundary-reference points, the authors established a priori constraint for extracting the boundary of the measured part. Combining with the image features of background and the measured part, an image-edge compensation model is established to extract the boundary of the measured part. The critical point of a laser stripe on the edge of the measured part is extracted corresponding to the boundary constraint. Finally, as per the principle of binocular vision, the profile of the measured part is reconstructed.

Laboratory experiments validate the measurement accuracy of the proposed method which is 0.33 mm. In the analysis of results between the measured data and the theoretical model, the measuring accuracy of the proposed method was found to be significantly higher than that of the other traditional methods.

An aviation part was measured in the part-assembly shop by the proposed method, which verified the feasibility and effectiveness of this method. The research can realize the measurement of smooth surface boundary which can solve existing profile reconstruction problems for aviation parts.

According to the two-dimensional contour constraint, critical points of the laser strip sequence at the edge of measured part are extracted and the accurate profile reconstruction with the boundary is realized.

The purpose of this paper is to examine various aspects of regional and global production networks, with a special focus on China.

The author studies four different approaches to measure production networks and discuss their strengths and weaknesses. The author presents some of the results associated with some of these measurements.

The author finds that using trade data alone is simple but incomplete. Bringing in input–output tables is useful but much more data would be needed. In addition, for the case of China, electronic goods and telecommunication goods tend to have a higher foreign value added.

Data with good quality can be a problem. The authors also have difficulty getting input–output tables for many years.

The results can guide policymakers as to which industries can create more domestic value added. The results can also lead to betting of an understanding of trade balances measured in the value added.

The results can generate further understanding among citizens of many different countries, including China, about the importance of different sectors in generating the value added.

The value of this paper is to focus on alternative ways to measure the value added in exports from China. The paper is the first to discuss the strengths and weaknesses of different approaches and present some of these results.