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排序方式: 共有119条查询结果,搜索用时 31 毫秒
101.
102.
采用实例推理和遗传算法相结合的方法,研究了航空机械零部件失效模式识别的问题。对用于识别的失效属性的选择、检索相似度计算、训练用遗传算法的适应度函数设计以及训练策略的影响进行了较为详细的描述。应用测试表明,对包含分布均衡的3种模式的情况取得了高于74.67%的识别率,所获得的最佳权值向量对另外2种模式具有很好的识别精度(大于73.3%),对混合多模式情况也具有较好的推广能力。验证了该方法对航空零部件失效模式的识别是可行的。 相似文献
103.
Abstract We propose and systematically formalise a dynamical spatial systems approach for the modelling of changing spatial environments. The formalisation adheres to the semantics of the situation calculus and includes a systematic account of key aspects that are necessary to realize a domain-independent qualitative spatial theory that may be utilised across diverse application domains. The spatial theory is primarily derivable from the all-pervasive generic notion of “qualitative spatial calculi” that are representative of differing aspects of space. In addition, the theory also includes aspects, both ontological and phenomenal in nature, that are considered inherent in dynamic spatial systems. Foundational to the formalisation is a causal theory that adheres to the representational and computational semantics of the situation calculus. This foundational theory provides the necessary (general) mechanism required to represent and reason about changing spatial environments and also includes an account of the key fundamental epistemological issues concerning the frame and the ramification problems that arise whilst modelling change within such domains. The main advantage of the proposed approach is that based on the structure and semantics of the proposed framework, fundamental reasoning tasks such as projection and explanation directly follow. Within the specialised spatial reasoning domain, these translate to spatial planning/re-configuration, causal explanation and spatial simulation. Our approach is based on the hypothesis that alternate formalisations of existing qualitative spatial calculi using high-level tools such as the situation calculus are essential for their utilisation in diverse application domains such as intelligent systems, cognitive robotics and event-based GIS. 相似文献
104.
Jennifer Smith Mason Alexander Klippel Susanne Bleisch Aidan Slingsby Stephanie Deitrick 《Spatial Cognition & Computation》2016,16(2):97-105
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
105.
内窥检测在航空发动机维护中得到广泛应用,但是目前的人工检测方式已经难以满足民航业的需求,将智能诊断专家系统引入到航空发动机内窥故障检测中,并集合了基于规则的专家系统和基于案例的专家系统的优点.研究了一种航空发动机内窥检测智能诊断混合专家系统,该系统首先对处理后的内窥图像进行规则推理,若无法找到匹配规则再转入案例推理,直至给出故障诊断结果和维修策略。通过实验检验,专家系统可以准确、快速地给出诊断结果。 相似文献
106.
ABSTRACTKnots can be found and used in a variety of situations in the 3D world, such as in vines, in the DNA, polymer chains, electrical wires, in mountaineering, seamanship and when ropes or other flexible objects are involved for exerting forces and holding objects in place. Research on knots as topological entities has contributed with a number of findings, not only of interest to pure mathematics, but also to statistical mechanics, quantum physics, genetics, and chemistry. Yet, the cognitive (or algorithmic) aspects involved in the act of tying a knot are a largely uncharted territory. This paper presents a review of the literature related to the investigation of knots from the topological, physical, cognitive and computational (including robotics) standpoints, aiming at bridging the gap between pure mathematical work on knot theory and macroscopic physical knots, with an eye to applications and modeling. 相似文献
107.
Ernest Davis 《Spatial Cognition & Computation》2013,13(4):264-294
Abstract Simple natural language texts and narratives often raise problems in commonsense spatial knowledge and reasoning of surprising logical complexity and geometric richness. In this article, I consider a dozen short texts—five taken from literature, the remainder contrived as illustrations—and discuss the spatial reasoning involved in understanding them. I conclude by summarizing their common features, and by tentatively drawing some morals for research in this area. 相似文献
108.
基于D-S证据理论的GPS/MM组合系统车辆定位算法 总被引:9,自引:0,他引:9
根据分段、特征提取等地图匹配关键技术探讨了地图匹配的一般原理,提出了基于D-S证据推理理论的GPS(Global Positioning System)/MM(Map Matching)组合算法,提高了GPS单点定位精度.仿真结果和跑车实验验证结果表明上述方法是行之有效的.地图匹配算法不增加系统的硬件成本,对目前广泛应用的车载GPS导航定位系统是一个有效的解决方案. 相似文献
109.
提出了一种多媒体数据库语义检索原型MSFRP。介绍了系统原型设计及其多媒体对象分割匹配技术,设计了多媒体对象语义模型,描述了模糊推理检索方法。MSFRP实现从特征层到语义层的多媒体数据检索,有效支持多媒体数据库的复杂查询应用。 相似文献
110.
TCAS是保证飞机安全飞行的重要保障。本文分析了TCAS板卡的故障模型和电路结构,在故障诊断系统中引入案例推理方法,对增强TCAS板卡深度故障诊断的效率有很大帮助。 相似文献