Fault Knowledge Management And Reasoning Application Of Pump Truck Hydraulic System Based On Ontology

In order to ensure the safe operation of the concrete pump hydraulic system and reduce the maintenance costs, one of the important measures is the maintenance and fault diagnosis of hydraulic system. With the continuous development of technology, to realize the integrated use of the existing knowledge about hydraulic system has become an inevitable measure to optimize the maintenance and intelligent diagnosis. Under the guidance of knowledge, system maintenance can realize its knowledge integration and process optimization, then reduce the complexity of maintenance work, which will improve the maintenance efficiency; fault diagnosis can integrate the interrelated experience from various enterprises, automatically generating diagnostic strategy under the guidance of knowledge inference, which helps staff to complete maintenance tasks.The realization of system maintenance and fault diagnosis based on knowledge first need to complete the knowledge management. However, the knowledge about hydraulic system exists in different sectors, which have characteristics of heterogeneous structure, so it is not easy to realize effective knowledge integration by using some former methods. In order to realize the real ascension of knowledge management about hydraulic system of concrete pump, and make the hydraulic system maintenance and optimization of intelligent diagnosis acquire corresponding knowledge security, the thesis introduces the ontology knowledge representation and retrieval, carrying out an in-depth study on the knowledge management and application reasoning about the hydraulic system of concrete pump. The main research work of the thesis includes the following aspects:(1) According to the requirement of the knowledge management about hydraulic system of pump truck, the solution scheme of multi-source heterogeneous knowledge based on ontology for the hydraulic system of pump truck is put forward. The model uses ontology to describe variously domain knowledge and realize the overall knowledge integration through ontologymapping, under which the optimization of maintenance and fault reasoning of hydraulic system can realize the effective use of existing knowledge.(2) In the view of the massive and complex computation on the knowledge ontology mapping during the process of knowledge management about hydraulic system, the double perspective way of ontology mapping is designed.On this basis adding to ontology block theory, a new way is put forward, of which that basing on the extracted anchor point of ontology, a sub ontology is extracted from two original ontologys and the similarity propagation algorithm is designed semantically guided by the anchor point, completing the sub ontology mapping. Compared with the general method, it improves the mapping accuracy and reduces the amount of calculation, which lay the foundation for fault reasoning based on ontology of hydraulic system.(3) The fault reasoning method based on ontology of improved C-F model is designed. With the hydraulic system ontology as knowledge base, this method carries out the fault reasoning through the improved C-F model to establish inference rules engine. With the help of knowledge inference, the role of ontology is given a full play, whose result provides decisive support for staff at the same time.(4) A prototype system on knowledge management application of concrete pump is exploited, introducing the system framework and development process,including the ontology knowledge base, the reasoning scheme and the development of functional module, and the effectiveness of the system is verified by practical example.