The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Testability growth is a process that aims to improve the testability level of the equipment via identifying and removing the testability design defects (TDDs). The establishment of the existing testability growth model (TGM) needs to consider a variety of factors, it's difficult to describe it accurately. To solve this problem, a TGM based on evidential reasoning (ER) method with nonlinear optimization...
The point that the failure rate of a product tends to be steady and low from the high infant period is called change point. An ideal starting time of a warranty period should be exactly set as this point. The infant period of a life cycle is usually believed to be highly relative with the defects and failures which originated in production. However, due to the lack of studies on the mechanism of product...
Health condition estimation is an important means to guarantee the normal work and the optimal maintenance for CNC machine tool servo system. The health condition is denoted by features. In order to estimate the health condition for servo system, belief-rule-base (BRB) model is employed as estimation method in this paper. This method can composite multiple knowledge including some uncertain information...
The model of the pantograph and catenary system is established based on the commercial finite element analysis software ANSYS. And the dynamic performance of the pantograph-catenary system at different speed is simulated. Meanwhile, the reliability of the simulation model was verified by comparing the contact force with the test data. In order to enhance the dynamic performance and quality of the...
Wireless localization can provide position information for limitary, aerospace, emergency scheduling, rescue and relief work, fault diagnosis and many other related location-based services system in various application fields. Location information always supports critical decision-making of these application systems. So the localization accuracy is of great importance. As availability, low computation...
When faults happen at gas path components of gas turbines, some charged abnormal debris will be generated. An electrostatic sensor can be installed at the tail end of the exhaust pipe to monitor the abnormal debris online and further indicate the faults. However, the electrostatic sensor itself is faced with a problem of function failure because of a severe working condition of high temperature and...
In this paper, we propose to optimize both the assignment of missions and the maintenance scheduling of moving systems (e.g. trains) in a Prognostics and Health Management (PHM) context. The problem is to associate a system to each mission and to integrate the necessary maintenance operations in the schedule according to the real state of health of systems. This problem, which falls within the decision...
Degradation of multi-component system exists widely in the field of engineering. And the degradation failure of multi-component system is due to the overall degradation of the system to a certain extent, or the degradation of component. In this paper, we focus on the reliability model of multi-component degradation system, which failure caused by degradation of component failure, was simplified and...
Testability optimization is an important part of testability design. In the past, testability optimization design often neglects the correlation between testability and reliability and does not pay much attention to the influence of system reliability. Considering such circumstance, this paper studies the impact of the basic reliability of the system and the Built-In Test (BIT) working mode. Different...
This paper studies reliability allocation methods for aircraft engines. The objective of the research is to develop an effective reliability allocation method for complex systems when only limited data can be obtained. A practical approach is proposed by considering complexity of the engine and data availability. Using this method, MTBF and Dispatch Reliability targets can be decomposed from higher...
The automatic recognition of hidden defects plays a key role in the structure integrity and healthy monitoring (SIHM) system. The article proposes a novel method that combines the Hilbert Huang transform (HHT) and hybrid support vector machine-particle swarm optimization (Hybrid SVM-PSO) model for recognizing hidden defects during using pulsed eddy current (PEC) testing. The proposed approach uses...
Aiming at some characteristics of servo valves that the complex influence between the failure modes and the high order nonlinearity of the fault datum, this paper presents a fault diagnosis model-Deep Intelligent Generalized Regression Neural Network (DGN). The DGN is a supervised deep learning model. In order to fully learning the fault datum, this paper proposed a logistic mapping and dynamic step...
Different kinds of operating environment and multiple mission conditions result in dynamic mission definitions, stages and profiles of complex systems like avionic systems in airplanes. A complex system usually consists multiple parts, units or subsystems which perform limited functions and are hardly under operation for all time. Based on such circumstances, traditional system reliability and testability...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.