As an important source of inspiration, the great number of patent documents provides designers with valuable knowledge of design rationale (DR), including issues, intent, pros and cons of the solutions. Researchers have carried out a number of data analysis studies based on patent information, which is now a new discipline called Patinformatics, including the analysis of patent information from a macro perspective and the identification and extraction of patent knowledge from a micro perspective. If DR knowledge could be extracted automatically from the patent documents and provided to designers as a source of inspiration, it would greatly promote innovative design, and at the same time promote the reuse of patent documents and the wide application of DR theory, which can be like killing three birds with one stone. To address this issue, this study proposes an improved lexical-syntactic pattern method for DR centric patent knowledge extraction, including DR Vector Space model (DRVS), DRV Trigger Word (DRV-TW), Design Rationale Vector (DRV), DR credibility (DRC) and others, and DRV based knowledge extraction algorithms. Knowledge extraction experiments were conducted on 1491 patent documents to verify the feasibility and performance of the method. In addition, two other sets of comparative experiments were conducted using the FastText and BERT machine learning methods, and the results further confirmed the reliability of the proposed method for lowresource corpus.INDEX TERMS Patent analysis, design rationale, knowledge extraction, design knowledge network.

Multidisciplinary reliability analysis (MRA) is an important part of reliability-based multidisciplinary design optimization (RBMDO). In order to solve the problem of low computational efficiency caused by nested loops in multidisciplinary reliability analysis, an efficient multidisciplinary reliability analysis method based on decoupling idea is proposed. The method decouples system analysis, system sensitivity analysis and reliability analysis of Single discipline to form a recursive cycle, which eliminates the complete optimization calculation of reliability analysis model by system-level optimizer in each iteration. In the process of system sensitivity analysis, the global sensitivity equation is used to perform the concurrent subspace sensitivity analysis, which improves the efficiency of MRA. The decoupled multidisciplinary reliability analysis can get rid of the restriction that the traditional reliability analysis can only be carried out by using nonlinear optimization method, and the modified advanced mean value (MAMV) and other most probable point (MPP) search algorithms can be used to solve the reliability problem. Finally, three examples are used to verify the effectiveness of the method.