The Research On The Fault Diagnosis Expert System For Aviation Engine Based On Function Model

With rang of use of air force increased and war efficacy strengthened. Being first used and being whole used is the true-to-life portrayal of the local war under the advanced technology. In order to make sure that the air force wins at any time, it is very essential for aviation equipments to keep and recover reliability. Any equipment will be transformed from reliable status to unreliable status sooner or later when they are used, or they are affected by inner and exterior factor. The aviation maintenance is the work to fix or maintain the aviation equipment, whit the purpose of keeping and recovering the reliability of the equipment, ensuring the equipments are used safely, and making the equipment functional, only in this way can air force perform the tasks efficiently. The aviation glimmer work is to perfect the commanded maintenance works and fixed works in time, if these works are delayed, the airplane would put off or delay takes off, in wartime, it would result serious loss. Many breakdowns occur randomly during the airplane flying, many system's breakdowns involve lots of profession, and are difficult to diagnose. But all the breakdowns required fix quickly .To complete the task, the employee must be skillful. In recent years. The artificial intelligence technique enters to the impediment diagnosis realm to form a kind of all new intelligence impediment diagnosis method. The intelligence diagnosis system is a kind of technique guided by the artificial knowledge .It fully sum the mankind's analytical skill to the affairs, using of the artificial intelligence method to deliver, handle, rebirth and make use of the information, the method has the ability to recognize and forecast the affairs in the future. Its successful example is the development of the impediment diagnosis expert system. The development of the impediment diagnosis expert system is to design a kind of program by combining the expert's knowledge with the calculator technique, and according to the proper detective method to design the computer program .the operator dialog with the computer and answer the computer's questions, so the impediment diagnosis system offer the operator correct result. To diagnose the system correctly, we should comprehend the system correctly and detect correctly. It is easier to build the rule library if we make a clear and easy description to the system before we build the library .so we should first build a modal, the modal compiles the knowledge regularly and layerlly organized. In this article, the function modal is different from other modals in the feature of function; the function modal involves the knowledge of function. The function of the technique system is objective and belongs to the system itself; the description should obey the follow rules: (DThe objective contents; (2) The unique meaning; (3) The proper abstracting; (4) The full information; (5) The general using; (6) The easily using . In this article, we define the function as follows conception: Under the particular condition, the objector has the ability to make its function objector's existing status change, the ability showed by the changes of the function objector's existing feature, if a function corpus makes a several changes of its function objector .we say that the function corpus has several functions. The objector's existing status can be expressed by the objector's existing feature; each feature reflects an existence of a status. The changing of status of the function objector due to the existing feature. Once the objector 's existing feature changes, we say that the function corpus has a function. One of the function corpus ' s functions is the description of the function objector 's existing feature. In this article, we express the function as the follow formulation: Feature (Masten, Objectj, Value K.F-Condition,M-Condition)...