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1.
With question answering system in medicine, users could use sentences in daily life to raise questions. The question answering system will analyze and comprehend these questions and return answers to users directly. Aiming at the problems in automatic diagnosis for medicine, such as low precision of question answering, imperfect expression of domain knowledge, low reuse rate, and lack of reasonable theory reference models, we put forward the information integration method of semantic Web based on pervasive agent ontology (SWPAO method) in medicine, which will integrate, analyze, and process enormous Web information and extract answers on the basis of semantics. A novel approach for automatic diagnosis in medicine based on ontology and fuzzy rough set is brought forward. The data mining algorithm for automatic diagnosis rules in medicine is brought forward: (1) computing the measurement matrix of effect; (2) extracting rules; (3) computing the importance of rules; (4) shearing the rules by genetic algorithm. In this paper, rough sets method is used to take potential diagnosis rule from the decision‐making table in medicine. These rules can offer effective automatic diagnosis service. With the SWPAO method as the clue, we mainly study the method of concept extraction based on uniform semantic term mining, pervasive agent ontology construction method on account of multipoints and the answer extraction in view of semantic inference. Meanwhile, we present the structural model of the question answering system applying ontology, which adopts OWL language to describe domain knowledge base from where it infers and extracts answers by Jena inference engine, thus the precision of question answering in QA system could be improved. In the system testing, the precision has reached 86% and the recalling rate is 93%. The experiment indicates that this method is feasible, and it has the significance of reference and value of further study for the question answering systems in medicine. © 2010 Wiley Periodicals, Inc.  相似文献   

2.
从已有的数据模型中进行语义提取,经过一定的规则映射生成本体的过程称为本体学习。关系数据库模型是当前数据的存取与组织的主要模型,从中学习得到本体,一直是本体工程领域研究的热点之一。利用手工定义的E-R模型到本体的映射规则来完成本体的构建,是国内外大部分学者采用的方法。但这样获得的本体概念层次关系主观依赖性强,不利于本体的实际应用。为了能更加客观地获取数据之间的概念层次关系与语义信息,提出了一种基于FCA(形式概念分析)从关系数据库进行本体学习的方法。该方法既保持了关系数据表中原有的数据语义关系,又发挥了FCA自动提取语义信息的特点,提高了最终本体生成的质量,有利于在具体的领域应用中使用本体。最后结合材料服役安全数据库的数据信息,演示了运用所提出的方法学习得到领域本体的过程。  相似文献   

3.
探讨一种基于数据融合和可拓理论的电力变压器故障诊断方法,基于此方法,应用无线传感器网络技术和.NET开发平台构建和开发出一套电力变压器故障诊断系统。该系统将WSN技术用于电力变压器油中溶解气体的无线数据采集,实现变压器油中溶解气体的实时数据采集和传送;同时运用信息融合技术对数据进行优化处理,既可以降低网络能耗又保证了数据的准确和客观;在变压器进行故障诊断时,针对现有电力变压器故障诊断的气体比值法存在的编码规则不完整、诊断故障类型单一等缺陷,使用可拓诊断方法,定量与定性相结合,使变压器故障诊断方法更为精细化。在线故障诊断可视化系统可以实现变压器油中溶解气体参数的采集、显示、分析、存储和回放等功能,实现对变压器故障信息的实时分析与自动诊断,既解决了作业人员远程实时监测变压器运行状态问题,又大大提高了变压器故障诊断的性能,为变压器在线监测和故障诊断技术提供新的发展方向。  相似文献   

4.
基于本体不确定性推理的故障诊断   总被引:1,自引:0,他引:1       下载免费PDF全文
针对航空维修行业内不同角色企业故障诊断知识、系统、资源的分散、封闭、异构等原因导致的故障知识不易共享、重用的问题,采用本体来构建故障知识库;并设计其本体知识模型结构,以表达故障现象与故障结论间存在的不确定性关系;进一步编写相应的推理规则,设计基于本体的不确定性推理系统。以飞机发动机故障诊断为例进行了验证。  相似文献   

5.
Despite extensive research in the area of model-based fault diagnosis, the number of applied solutions is still rather limited. The reason for this is to be partly sought in the relatively high costs related to the development of a diagnostic system. Hopefully, the efficiency of the development cycle can be substantially improved with the use of computer-aided design (CAD) tools. This fact served as a major motivation for the realisation of a CAD prototype which performs automatic synthesis of rule-based diagnostic systems for industrial processes. The tool relies on fault propagation models and an object-oriented modelling paradigm. A model of the whole process derives from the component models and information about the way the components are interconnected. As the library of component models is inherent to the tool, the major input expected from the user is a process flowsheet. This can be simply provided through a graphic user-interface. The synthesis of propagation models, and synthesis of the rules thereof, is performed using an automatic synthesis procedure. An algorithm that transforms fault trees into event trees and diagnostic rules is presented. Handling complex structures, such as feedback loops, is also addressed. For on-line execution of the resulting diagnostic rules, the approximate reasoning scheme referred to as the transferable belief model (TBM) is suggested. The underlying CAD tool is suitable for performing several routine tasks that occur in the process of the development of a diagnostic system. This is illustrated on an example of a laboratory test rig.  相似文献   

6.
This paper models the traffic light control domain using a fuzzy ontology and applies it to control isolated intersections. Proposing an independent module for reusing traffic light control knowledge is one of the most important purposes of this paper. In this way, software independency increases and other software development activities, such as test and maintenance, are facilitated. The ontology has been developed manually and evaluated by experts. Moreover, the traffic data is extracted and classified from images of intersections using image processing algorithms and artificial neural networks. According to predefined XML schema, this information is transformed to XML instances and mapped onto the fuzzy ontology for firing suitable fuzzy rules using a fuzzy inference engine. The performance of the proposed system is compared with other similar approaches. The comparison shows that it has a much lower average delayed time for each car in each cycle in all traffic conditions as compared with the other ones.  相似文献   

7.
针对复杂航空装备诊断知识缺乏、诊断效率低和知识共享性差等问题,以某型红外弹为例,提出一种基于OWL本体和SWRL规则的导弹智能故障诊断方法。首先以导弹FMECA结果作为知识源,通过基于ATML语法的OWL逻辑描述语言建立导弹本体模型,完成故障模式和故障原因本体之间的映射;其次采用语义网络规则语言SWRL描述知识库规则,建立本体知识单元之间类、属性和实例的对应关系,最后通过Racer推理机对导弹知识库进行故障诊断推理,获取故障诊断优先级顺序。推理结果表明,该方法能够解决复杂航空装备专家诊断系统中的知识表示困难、缺乏自动语义推理、重用共享性差等问题,获得最优的故障诊断路径的同时减少了故障排查步骤,从而实现了故障原因的快速定位,提高了复杂航空装备专家诊断系统的诊断效率和可靠性。  相似文献   

8.
Fault prediction and fault compensation are beneficial for the production technology and give a new dimension to fault diagnosis in technical systems. The overall goal of this paper is the presentation of fault prediction and fault compensation procedures as they are studied, implemented and embedded in a real time expert system. This expert system detects and diagnoses faults in hydraulic systems. For this purpose dynamic modelling information, on-line sensor information, special features of the domain of hydraulic systems and expert systems technology are used co-operatively.  相似文献   

9.
当前由于缺乏完整的转换规则描述和相应的实现机制,难以实现灵活、自动的模型转换。采用基于本体的方法来建立模型元素之间的映射关系,并结合本体描述语言给出了模型元素和转换规则在本体库中的描述方法,实现了在两个不同的计算无关层(CIM)建模工具所建模型之间的自动转换。该成果已成功地应用到基于MDA的军工企业数字化项目中。  相似文献   

10.
灰色动态预测在AUV传感器故障诊断中的应用   总被引:2,自引:0,他引:2  
针对自主水下机器人(AUV)传感器故障诊断中样本数据少、随机性强、实时性要求高的特点,将灰色动态预测模型的建模原理引用到AUV传感器的故障诊断中。在对传感器进行数据滤波、小样本灰色建模与灰色动态预测的基础上,可以实现AUV传感器的实时故障诊断。文章详细阐述了基于灰色动态预测的传感器故障诊断的具体实现方法和步骤,对AUV传感器中典型的四种故障模式进行了仿真研究。结果表明该方法能快速、准确地诊断出传感器故障,并且在传感器发生故障后的一段时间内能够实现信号恢复。  相似文献   

11.
为保证机场场面运行安全,从知识建模角度出发,提出智能信息处理方法诊断违规项目,使用SWRL、领域本体等技术构建跑道侵入违规诊断系统的本体模型。研究了将跑道侵入案例用语义规则形式化表示的方法,构建推理规则得出违规项目和硬件预防措施。结果表明,提出的方法较传统方法,结合本体和SWRL推理技术的方法准确率更高,性能更佳。  相似文献   

12.
针对基于Web页面信息本体的信息抽取中,需人工根据待抽信息项的概念和对应的实例值来建立本体的缺点,设计一个页面信息本体的自动学习方法。论文利用前期在基于DOM的页面相似路径归纳学习算法和基于PAT-tree的自动关键词识别算法上的研究成果,使用改进的TF.IDF统计方法和复合事件的关联规则算法完成概念和概念间关系的学习,建立页面信息本体,减少建立本体的人工工作量。  相似文献   

13.
提出一种实用的分层故障字典诊断模型。首先进行子网络撕裂,缩小字典规模,随后运用交流故障字典法划分故障模糊集,最后运用直流故障字典法定位故障元件。该诊断模型有效地克服了传统故障字典方法中字典规模过于庞大的缺点。并且便于实现模拟电路的自动测试,故障定位准确率高。文中同时阐述了算法的应用和软硬件设计要点,并在某高炮控制系统模拟电路故障诊断中得到了应用。  相似文献   

14.
基于规则映射的Web服务自动组合   总被引:1,自引:0,他引:1  
针对目前多数Web服务组合流程需要人工设计的问题,提出一种基于输入输出参数与规则关联映射自动构建Web服务组合路径的方法。该方法首先给出产生式规则库,并对输入输出参数本体建模,然后从用户给定的输入出发,建立输入输出参数与规则相关联的映射表,在映射表中由用户期望的输出开始回溯找出所有满足条件的组合路径,最后根据服务质量描述,选取最优的组合方案返回给用户。  相似文献   

15.
张定会 《微型电脑应用》2000,16(7):37-39,55
本文介绍了PC机与过程计算机间如何实现正确数据通信的方法。其中PC机作为上位机,用于运行故障诊断专家系统;过程计算机是德国西门子SIEMENS R30过程计算机,用来监测和控制某钢厂大型冷轧自动化生产线。该方法既保证了故障诊断专家系统对过程计算机及整个生产线实时地进行状态监测和故障,又不影响过程计算机本身对生产过程的监测和控制。  相似文献   

16.
基于多传感器的发动机故障诊断模糊专家系统   总被引:3,自引:4,他引:3  
本文介绍了采用多传感器综合监测技术的汽车发动机故障诊断专家系统。总结了汽车发动机常见故障,建立了汽车发动机典型故障集。介绍了汽车发动机的故障征兆提取方法,建立了汽车发动机故障征兆集。提出了一种基于模糊规则汽车发动机故障诊断方法。设计了基于模糊规则的发动机故障诊断专家系统,并通过实例证明了该诊断系统的有效性。  相似文献   

17.
现有的照片管理系统缺乏自动语义推理和扩展功能。为此,提出一种基于本体的智能照片管理系统。该系统以FamilyAlbum本体模型为知识框架,对照片进行多源信息的语义标注,并利用SWRL规则对系统中现有的语义标注进行自动推理,从而扩展出新的语义信息,为照片的智能管理提供有效支持。通过OntoAlbum原型系统的实现,验证了该方法的有效性。  相似文献   

18.
利用单一信息对雷达发射设备进行故障检测和诊断时,可靠性和准确性低。针对雷达发射设备器件温度反映发射机工作性能明显的特点,提出了基于电传感器和温度传感器等多传感器信息融合的快速故障诊断方法。给出了故障诊断中信息融合的模型和算法,讨论了多传感器信息融合的雷达发射设备故障快速诊断系统的组成和简单工作原理。在提高复杂电子装备故障诊断可靠性和准确性上提供了一条有效途径。  相似文献   

19.
针对一类带随机丢包的异步多传感器网络化系统,提出了基于网络化异步交互式多模型(Interacting multiple model,IMM)融合滤波的故障诊断方法.考虑不同传感器通道具有不同丢包概率的情况,将未知的故障幅值看作扩维的系统状态,利用提出的网络化异步IMM融合滤波算法对由系统正常模型和各种可能的故障模型构成的模型集进行滤波,根据模型概率进行故障检测和定位,同时得到故障幅值和系统状态的联合估计.提出的方法避免了传统IMM故障诊断方法模型集设计中故障大小难以确定的问题,适用于具有任意采样速率和任意初始采样时刻的异步多传感器网络化系统,并且通过融合多个传感器的信息提高了故障诊断的准确性.仿真实例验证了所提出方法的可行性和有效性.  相似文献   

20.
基于VI的恒温区段测量系统设计   总被引:1,自引:2,他引:1  
在半导体器件的生产过程中需要定期测量扩散炉、合金炉的恒温区段,针对人工测量效率低,精度差等问题,设计了基于LabVIEW虚拟仪器的恒温区自动测量系统,阐述了系统的组成和测量原理。  相似文献   

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