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291.
While research on uncertainty and decision-making has a long history across several disciplines, recent technological developments compel researchers to rethink how to best address and advance the understanding of how humans reason and make decisions under spatial uncertainty. This introduction presents a visual summary graphic to provide an overview of each article in this special issue. Upon viewing these visual summaries, the reader will find that each of these articles covers different topics in the uncertainty visualization domain, offering complementary research in this field. Extending this body of research and finding new ways to explore how these visualizations may help or hinder the analytical and reasoning process of humans continues to be a necessary step towards designing more effective uncertainty visualizations to support reasoning and decision-making.  相似文献   
292.
在有人参与的控制过程研究中,确定人操作者的模糊控制模型的参数是非常困难而复杂的一步,也是此研究领域的一个重点。这个问题的解决,将对人一机控制系统的研究,分析和设计有着十分重要的意义。 本文根据已知的人的模糊控制模型,提出了一种参数辨识方法,并进行了参数辨识实验。实验结果表明:此辨识方法简单方便、且十分有效而实用。它不仅可以为人的模糊控制模型的研究提供基本数据,而且为参数辨识研究提供了新的途径。  相似文献   
293.
复合材料舷窗结构作为飞行器的重要组成部件,对其强度进行研究具有重要意义。采用试验与数值模拟相结合的方法对舷窗结构的力学行为进行研究,首先得到结构件的极限剪切载荷,然后建立基于连续介质损伤力学(CDM)的数值模型进行仿真模拟。结果表明:所建立的数值模型可以准确预测结构件的强度值及损伤破坏部位。  相似文献   
294.
复杂装备研制项目的风险源识别   总被引:1,自引:1,他引:0  
大型复杂装备研制项目高风险与参研单位多的特点使得研制过程中风险传导时有发生。针对风险传导要素风险源的识别问题,提出了一种基于关联规则(AR)与决策实验室分析法(DEMATEL)的风险源识别方法。该方法从数据挖掘的角度,先求解出风险类型与风险因素的关联规则,再求解出风险源之间的影响程度,最后通过DEMATEL得到各风险源相关参数。并且对某参研单位数据库中某阶段的数据用此方法完成了风险源的识别,识别结果显示了各风险类型对应的风险源以及易导致研制项目发生风险传导的风险源。  相似文献   
295.
针对内河船舶工况启停变化频繁导致瞬态动力性较差、动态响应较慢等问题,提出并联气电混合动力系统改进方案,利用模糊逻辑推理方法来提升动力响应性能。以某内河拖船为研究对象进行混合动力系统参数匹配设计,通过对系统关键参数设计切换规则,建立基于逻辑门限的能量管理控制策略;为进一步优化逻辑门限方法主观设定边界阈值不可调节问题,提出基于“模糊逻辑推理+动态协调”能量最优分配策略。通过最优设计相关试验验证管理策略,结果表明:采用基于模糊逻辑推理的能量管理策略能使天然气发动机的平均负荷提升37.86%,平均效率提高2.74%,动态响应时间缩短44.45%。  相似文献   
296.
《中国航空学报》2022,35(8):179-192
In the research of uncertain information processing, Dempster-Shafer Theory (DST) provides a framework for dealing with uncertain information, where evidence is defined on a Frame of Discernment (FOD) consisting of mutually exclusive elements. However, the requirement of exclusiveness on FOD sometimes is not satisfied, as shown in Dezert-Smarandache Theory(DSmT), a derivative of DST. In DSmT, the non-exclusiveness is expressed by propositions’ intersection and the fusion of evidence is realized through a Proportional Conflict Redistribution (PCR) rule. In order to handle non-exclusive FODs, a new framework called D Number Theory (DNT) has been proposed recently, which quantifies the non-exclusive degree between propositions different from DSmT. In previous studies, an Exclusive Conflict Redistribution (ECR) rule has been designed in DNT to implement the fusion of evidence defined on a non-exclusive FOD, but there are some deficiencies in the ECR rule. In this paper, a new rule called ECR-PCR rule is proposed by combining the ECR and PCR rules to better implement the fusion of evidence defined on a non-exclusive FOD. Within the proposed rule, the definition of conflict utilizes the idea of ECR’s exclusive conflict, and the disposal of conflict is following the idea of PCR’s proportional redistribution. Properties of the ECR-PCR rule are presented. The effectiveness of the proposed new rule is verified through numerical examples and applications, in comparison with other fusion methods.  相似文献   
297.
《中国航空学报》2023,36(5):306-327
Evidential Reasoning (ER) rule, which can combine multiple pieces of independent evidence conjunctively, is widely applied in multiple attribute decision analysis. However, the assumption of independence among evidence is often not satisfied, resulting in ER rule inapplicable. In this paper, an Evidential Reasoning rule for Dependent Evidence combination (ERr-DE) is developed. Firstly, the aggregation sequence of multiple pieces of evidence is determined according to evidence reliability. On this basis, a calculation method of evidence Relative Total Dependence Coefficient (RTDC) is proposed using the distance correlation method. Secondly, as a discounting factor, RTDC is introduced into the ER rule framework, and the ERr-DE model is formulated. The aggregation process of two pieces of dependent evidence by ERr-DE is investigated, which is then generalized to aggregate multiple pieces of non-independent evidence. Thirdly, sensitivity analysis is carried out to investigate the relationship between the model output and the RTDC. The properties of sensitivity coefficient are explored and mathematically proofed. The conjunctive probabilistic reasoning process of ERr-DE and the properties of sensitivity coefficient are verified by two numerical examples respectively. Finally, the practical application of the ERr-DE is validated by a case study on the performance assessment of satellite turntable system.  相似文献   
298.
《中国航空学报》2023,36(3):184-201
It is vital to establish an interpretable fault diagnosis model for critical equipment. Belief Rule Base (BRB) is an interpretable expert system gradually applied in fault diagnosis. However, the expert knowledge cannot be utilized to establish the initial BRB accurately if there are multiple referential grades in different fault features. In addition, the interpretability of BRB-based fault diagnosis is destroyed in the optimization process, which reflects in two aspects: deviation from the initial expert judgment and over-optimization of parameters. To solve these problems, a new interpretable fault diagnosis model based on BRB and probability table, called the BRB-P, is proposed in this paper. Compared with the traditional BRB, the BRB-P constructed by the probability table is more accurate. Then, the interpretability constraints, i.e., the credibility of expert knowledge, the penalty factor and the rule-activation factor, are inserted into the projection covariance matrix adaption evolution strategy to maintain the interpretability of BRB-P. A case study of the aerospace relay is conducted to verify the effectiveness of the proposed method.  相似文献   
299.
对成败型航空发动机部件可靠性增长试验抽样数的确定问题进行了研究。推导出了初始故障数服从典型离散分布时的最小化最大准则(Max-Min准则),提出了一种逐次抽样样本估计值反馈修正方法。最后给出了一个应用实例,验证了该方法的有效性。  相似文献   
300.
Due to the excellent performance in complex systems modeling under small samples and uncertainty, Belief Rule Base(BRB) expert system has been widely applied in fault diagnosis. However, the fault diagnosis process for complex mechanical equipment normally needs multiple attributes, which can lead to the rule number explosion problem in BRB, and limit the efficiency and accuracy. To solve this problem, a novel Combination Belief Rule Base(C-BRB) model based on Directed Acyclic Graph(DAG) structu...  相似文献   
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