基于贝叶斯可信度的直升机安全性分析

本文基于贝叶斯网络理论建立了直升机在"人—机—环境系统"的飞行安全性模型,其目的是通过网络模型分析,发现影响安全性的薄弱环节,以及通过相应的纠正措施提高直升机飞行的安全性。     

基于社交网络视角的广西会展发展经济途径研究

社交网络不仅加速了会展信息传播速度、便捷了参展流程,改变了会展主体之间的沟通模式,也为会展经济的发展带来一场革命性的变革。在此种发展趋势下,本文对社交网络的内涵进行了分析,就社交网络对广西会展经济产生的影响进行总结和提炼,,并以会展行业需求为指导提出以社交网络为突破口加强广西会展经济发展的途径。     

模块化开放式航空电子系统架构标准研究

国外对开放式系统架构（OSA）概念的探索至今已有40 多年。美国国防部模块化开放式系统方法 （MOSA）正是建立在OSA 概念之上，综合了采办和工程方法，来实现低成本、优化和快速能力升级的武器 系统灵活开发。本文将集中讨论MOSA 构建方法及其开放式架构的最佳实践，包括开放式任务系统、未来机 载能力环境和传感器开放式系统架构。最后，本文讨论了MOSA 在开放式架构上开展的工作及其挑战，以期 对我国在航空电子OSA 标准研究和实践上有所裨益。     

熵损失下无失效数据的 Bayes估计

讨论了在熵损失下定时截尾数据的Bayes估计问题，将无失效数据看作逐次定时截尾试验的结果，进而得到无失效数据的Bayes估计，利用相关定理证明该估计是容许的。通过数值例子，进一步说明所得估计的合理性。     

A learning-based approach for solving shear stress vector distribution from shear-sensitive liquid crystal coating images

A learning-based approach for solving wall shear stresses from Shear-Sensitive Liquid Crystal Coating(SSLCC) color images is presented in this paper. The approach is able to learn and establish the mapping relationship between the SSLCC color-change responses in different observation directions and the shear stress vectors, and then uses the mapping relationship to solve wall shear stress vectors from SSLCC color images. Experimental results show that the proposed approach can solve wall shear s...     

Synthetic damage effect assessment through evidential reasoning approach and neural fuzzy inference: Application in ship target

The damage effect assessment of anti-ship missiles combines system science and weapon science, which can provide reference for the assessment of battlefield damage situation. In order to solve the difficulty of heterogeneous data aggregation and the difficulty in constructing the mapping between factors and damage effect, this paper analyzes the specific damage process of the anti-ship missile to the ship, and proposes a synthetic Evidential Reasoning (ER) – Adaptive Neural Fuzzy Inference System (ANFIS) to assess the damage effect. To solve the problem of fuzziness and uncertainty of criteria in the assessment process, the belief structure model is used to transform qualitative and quantitative information into a unified mathematical structure, and ER algorithm is used to fuse the information of lower-level criteria. In order to solve the problem of fuzziness and uncertainty of the information contained in the first-level variables, and the strong non-linear characteristics of the mapping between first-level variables and damage effect, the ANFIS with self-adaptation and self-learning is constructed. The map between the three first-level variables and damage effect is established, and the interaction process of the various factors in the damage effect assessment are clear. Sensitivity analysis shows that assessment model has good stability. The result analysis and comparative analysis show that the process proposed in this paper can effectively assess the damage effect of anti-ship missiles, and all criteria data are objective and comparable.     

Study on excitation force characteristics in a coupled shaker-structure system considering structure modes coupling

The interaction between an elastic structure and electrodynamic shakers commonly exists in Ground Flutter Simulation Tests(GFST) with multi-point excitations, causing a considerable discrepancy between the practical excitation forces and desired ones. To investigate the excitation force characteristics on a cantilever beam excited by a voltage-sourced electrodynamic shaker,the coupled shaker-beam system is modeled to derive the excitation force formula using Hamilton’s principle and Galerkin’s a...     

Autonomous navigation for lunar final approach based on gravity gradient measurements

Lunar final approach navigation is critical for pin-point lunar landing in future missions. This study investigates the use of lunar gravity gradient measurements for autonomous navigation of a lunar probe during the final approach phase. As the spacecraft approaches the Moon, the strength of gravity gradient signals improves. A spaceborne gravity gradiometer can precisely measure local gravity gradients, and the latest lunar gravity model GL1500E is used to provide reference values. The employed truncation degree and order of the gravity model are increased stepwise considering the decreasing altitude of the spacecraft in order to reach a compromise between computational costs and model accuracy. An iterative Kalman filter is developed for coupled orbit and attitude estimation using gravity gradient measurements and attitude quaternions obtained from star sensors. A simulated spacecraft with a gradiometer noise level of 0.01 E is considered. Simulation results show that the spacecraft’s position converges rapidly and achieves an accuracy of less than 100 m at the last epoch.