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在辅助决策系统概念的基础上,分析了海军航空反潜决策的特点。针对雷达、红外前视仪、声纳浮标、磁探仪和电子支援系统五种常用的搜索设备,用模糊综合评判法建立了单因素和多因素决策评价计算模型,并给出对两种搜索策略进行评价的算例。分析结果表明,用模糊数学方法进行定量计算,是建立辅助决策系统的有效途径之一,其过程可在计算机中编程实现。 相似文献
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《中国航空学报》2020,33(12):3395-3404
In this study, a Dual Smoothing Ionospheric Gradient Monitor Algorithm (DSIGMA) was developed for Code-Carrier Divergence (CCD) faults of dual-frequency Ground-Based Augmentation Systems (GBAS) based on the BeiDou Navigation Satellite System (BDS). Divergence-Free (DF) combinations of the signals were used to form test statistics for a dual-frequency DSIGMA. First, the single-frequency DSIGMA was reviewed, which supports the GBAS approach service type D (GAST-D) for protection against the effect of large ionospheric gradients. The single-frequency DSIGMA was used to create a novel input scheme for the dual-frequency DSIGMA by introducing DF combinations. The steady states of the test statistics were also analysed. The monitors were characterized using BDS measurement data, whereby standard deviations of 0.0432 and 0.0639 m for the proposed two test statistics were used to calculate the monitor threshold. An extensive simulation was designed to assess the monitor performance by comparing the Probability of Missed Detection (PMD) according to the differential error with the range domain PMD limits under different fault modes. The results showed that the proposed algorithm has a higher integrity performance than the single-frequency monitor. The minimum detectable divergence with the same missed probability is less than 50% that of GAST-D. 相似文献
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《中国航空学报》2020,33(12):3437-3446
Fault tolerance designs are essential techniques for systems that require high levels of reliability, such as aircraft or spacecraft control system. Imperfect Fault Coverage (IFC) may lead to the failure of a system or subsystem even with adequate redundancy. Previous studies of IFC mostly concentrated on evaluating Coverage Factor (CF), whereas the system failure behaviors with IFC have rarely been involved. Failures that occur in low-layer may be covered by high-layer. However, if the coverage is imperfect, uncovered failure will have functional and physical impact on the system behavior. In this thesis, the failure behavior and reliability of IFC of multi-layer systems are studied and a Binary Decision Diagram (BDD)-based modeling and simulation method are proposed to evaluate system reliability. As a case, the failure behavior of an aero engine electronic controller with IFC is studied. The results show that the IFC may impact system behavior without taking the IFC into account, the system maintenance intervals may reduce, and thus the maintenance costs will increase. 相似文献
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论文首先介绍了数据挖掘的概念及相关技术,然后论述了数据挖掘技术在金融信用决策管理系统中的应用,通过对预测解析、内在理解、决策建模、策略优化和策略精调的介绍,对数据挖掘的实现进行了有效描述. 相似文献
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提出了针对含有斑、点目标的遥感图像进行有损压缩的一种方法,介绍了去局部均值算法原理,依据3σ准则推导了门限取值公式,给出了算法的流程。通过仿真实验,分析了算法的有效性。 相似文献
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