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To obtain the global optimum of large‐scale complex engineering systems, the paper proposes a decomposition‐coordination method of multidisciplinary design optimization (MDO).

A rational decomposition approach based on artificial neural network (ANN) and genetic algorithms is proposed for partitioning the complex design problem into smaller, more tractable subsystems. Once the problem is decomposed into subsystems, each subsystem may be solved in parallel provided that there is some mechanism to coordinate the solutions in the different subsystems. So the response surface approximation model based on the ANN as a coordination method is described and a MDO framework is presented.

The proposed method was implemented in the design of a tactical missile. Numerical results show the effectiveness of the decomposition‐coordination method, as indicated by both better performance and lower computational requirements.

This paper adopts a novel MDO method to solve complex engineering problem and offers a potential and efficient MDO framework to researchers.

The essence of competition among modern enterprises is time; hence the time for product development must be greatly reduced. This paper presents a new process model of product development with uncertainty based on activity overlapping, borrowing ideas from the uncertainty model and activity overlapping model proposed by Loch and Terwiesch, and Krishnan respectively, to realize reduction on the time. Besides the fundamental framework of the proposed model, some derivations on the formula computing the total execution time of upstream and downstream activities are made. The effectiveness of the proposed model is verified through some further discussions and initial computational results.

The technical level of aircraft failure analysis plays a special role in ensuring the safety of civil aviation flight. Using appropriate methods for functional failures analysis can provide a reliable reference for aircraft safety. The purpose of this paper is to provide a new and comprehensive measure based on conventional functional hazard analysis (FHA) and grey system theory to analysis and evaluate the class that each failure belongs to.

This paper integrates multiple methods including the FHA, the fixed weight cluster, the Delphi method and the analytic hierarchy process (AHP). To begin with, use FHA method to sort out the corresponding failure states of a certain system from the perspective of function and determine the evaluation index. And then using group decision and AHP, determine the expert weight and index weight in the fixed weight cluster. The fixed weight cluster function is used to determine the grey class to which a certain functional failure belongs in the complex system.

In the past, the risk assessment of aircraft was mostly dominated by the subjective judgment of the experts, but it was not possible to give an objective observation score for each failure state. This paper addresses the problem efficiently as well as the feature of “little data, poor information.” The risk degree of each failure state can ultimately be replaced by a quantitative value.

This paper uses the idea of clustering in grey system theory to evaluate the risk of landing gear system. In the expert evaluation stage, different experts evaluated the impact degree of the aircraft's failure caused by its functions, so the final risk classification is subjective to some extent.

This study analyzed the different conditions of the landing gear, including the front wheel steering, front wheel damping, front wheel steering system, brake system fault information and so on. It can effectively divide the different failure states and their effects, which is helpful to improve the safety of aircraft landing gear system and provide some useful methods and ideas for studying the safety of aircraft systems.

Based on the FHA analysis process and the grey system theory, this paper determines various potential risks and their consequences of various functions according to the hierarchy, so as to carry out further detailed analysis on the risks that may occur under various functional conditions and take certain measures to prevent them. It is helpful to improve the risk management and control ability of aircraft in the actual flight process and to guarantee the safety of people's lives and property.

This paper is a pioneer in integrating the FHA method and the grey system theory, which exactly can be used to address the problem with the character of “little data, poor information.” The model established in this paper for the defects of FHA can effectively improve the accuracy of FHA, which is of great significance for the study of safety. In this paper, a case about landing gear system is given to illustrate the effectiveness of the model.