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Purpose The purpose of this paper is to propose a three-dimensional (3D) assembly model retrieval method based on assembling semantic information to address semantic mismatches, poor accuracy and low efficiency in existing 3D assembly model retrieval methods. Design/methodology/approach The paper proposes an assembly model retrieval method. First, assembly information retrieval is performed, and 3D models that conform to the design intention of the assembly are found by retrieving the code. On this basis, because there are conjugate subgraphs between attributed adjacency graphs (AAG) that have an assembly relationship, the assembly model geometric retrieval is translated into a problem of finding AAGs with a conjugate subgraph. Finally, the frequent subgraph mining method is used to retrieve AAGs with conjugate subgraphs. Findings The method improved the efficiency and accuracy of assembly model retrieval. Practical implications The examples illustrate the specific retrieval process and verify the feasibility and reasonability of the assembly model retrieval method in practical applications. Originality/value The assembly model retrieval method in the paper is an original method. Compared with other methods, good results were obtained.

A method is proposed to analyze and evaluate brittle source of the key procedure in increasing the stability during complex parts' manufacturing. Based on the concept of machining cell, brittleness risk is introduced into the stability analysis of manufacturing process; the key procedure in manufacturing process is obtained by analyzing and calculating the brittleness risk entropy of each machining cell. Moreover, brittleness factors of the key process are analyzed to obtain a human-machine-environment brittleness model from man-machine-environment. The improved fuzzy analytic hierarchy process (FAHP) is used to analyze the relationship between the brittleness factor and the brittleness event, and a quantification method of the brittle factor in the key process is given. Thus, dangerous brittle sources in key procedure as well as abnormal control points for anomalies can be identified to improve the stability of complex parts' manufacturing processes. Finally, the correctness and effectiveness of this method are verified by using the manufacturing process of an aeroengine blade.