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The functional principle and failure analysis of a landing gear cabin door lock mechanism are researched in this paper. The fastening process is important for achieving the mission of the mechanism. There are two potential risks in the fastening process that may impact the stealthy performance of an aircraft: accidentally open errors and lock hook position errors. These two risks compete with each other. Competing failure models are established for the fastening process of the lock mechanism. The extreme model is used to describe accidentally open failures, while Brownian motion (BM) with non-linear drift and the Poisson process are adopted to model lock hook position error failures. The reliabilities for the lock mechanism are calculated at different working times. Results and conclusions are illustrated and provide helpful insight into the changes and degradation of the fastening process of the lock mechanism. [ABSTRACT FROM AUTHOR]

A modified solvent casting/particulate leaching (SC/PL) method was developed to fabricate thick three-dimensional poly(lactic acid) (PLA) scaffolds with controlled pore size and porosity, and much shorter processing time. The pasty mixture of PLA/CHCl3/NaCl was sealed in a Buchner funnel by a piston with a suction flask connected. A vacuum pump was used to facilitate the volatilization of solvent. The scaffolds were obtained by subsequent removal of NaCl in deionized water. The pore size within the scaffold was in good accordance with the particle size of NaCl (< 210, 210∼310, 310∼420 and 420∼500 μm), all of which had more than 89 % of porosity, 1.95 ± 0.2 MPa of compressive modulus and non-cytotoxic to L929 cells. To demonstrate the applicability of the SC/VV/PL method, thick cylindrical and tubular porous scaffolds have been produced in this study. Compared with the traditional SC/PL without vacuum volatilization, the modified method, namely, solvent casting/vacuum volatilization/particulate leaching (SC/VV/PL) method, provide a more efficient way to fabricate thick scaffolds. [ABSTRACT FROM AUTHOR]