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PHM (Prognostics and Health Management) is an engineering technology focusing on failure prognostics and so it has critical effects on the performance of the task system. In this paper, the qualitative analysis method of FMEA (Failure Mode and Effects Analysis) is proposed to analyze the prognostics' performance of PHM system and five corresponding evaluation parameters are derived. Based on some...
In this article, we proposed a MARI&A model for single-unit and two-unit system maintenance. The model is combinations of arithmetic reduction of failure intensity and virtual age, which can be apply to continuous operating system with corrective maintenance and preventive maintenance during its maintenance process. Failure interactions and maintenance interactions among units are also taken into...
In this paper, a repairable system consisting of identical component is studied, both the mean time between failure (MTBF) of the component and the repair time are assumed to be exponentially distributed, Additionally, we assume that the component after a repair is “as good as new”. Maintenance strategies and the change of maintenance rate can affect the performance of the system, in order to further...
Availability allocation is required when the manufacturer is obliged to allocate proper availability to various components in order to design an end product to meet specified requirements. But in designing phase of products, design parameters such as components' failure rate and repair rate are normally under uncertainties. This paper presents a methodology for solving the availability allocation...
Aircraft operational readiness is one of the important indicators of military aircraft fighting capacity and equipment performance, which is closely associated with the reliability, testability, maintainability and supportability of the aircraft. Based on the analysis and existing research about the model of operational readiness of aircraft, the parameter value of model on evaluating operational...
Aiming at the problem of spares inventory in warranty logistics, this paper applies Markov modeling to the optimization of spares during the warranty period which considers the case where the repairable item is discarded, analyzes the transfer process of spares in operation, and stock, repair and discard of spares. In the Markov model, the actual situation of installation quantity of components in...
Simulation system with random factors presents new challenges to the software testing. The random factors in availability simulation system bring the uncertain running path and it is difficult for the test personnel to construct the expected output of the program. In view of this situation, this paper proposes a grey box testing method for availability simulation software based on event tree model...
In support process of equipment systems, spare inventory strategy, turnaround time, and product maintenance strategies have a great impact on system support time, and support time is one of the most important factors for the readiness and the task persistence of systems. Therefore, the use of reasonable spare inventory strategy, as well as maintenance and support decisions to systems is essential...
Availability indicates the degree of equipment or weapons systems to work properly when they are needed, spare parts are important factors that can influence operational readiness and mission sustainability of equipment, and its shortage has an indirect impact on the system availability. By supportability simulation analysis, many supportability parameters of system can be obtained; however, the complicated...
Support equipment is indispensable in the maintenance support process. Its allocation including what kind of support equipment and how many for each of them to be equipped determines whether relevant maintenance support tasks can be started and finished timely and effectively at maintenance support stations, and has a huge influence on the support system's cost, footprint and versatility. So far,...
In order to eliminate inter-symbol interference (ISI) in multi-h continuous phase modulation (CPM) systems due to the existence of multi-path in communications, frequency domain equalization (FDE) using a cyclic prefix (CP) is often used. However, to improve the synchronization and channel estimation, leveraging a training sequence of known symbols instead of a CP for multi-h CPM-FDE is more practical...
With the extensive application of new types of sensors, the rate of data acquisition and transmission are becoming a problem in Prognostic and Health Management(PHM). This paper presents an FPGA-based method for high speed data acquisition and transmission taking full advantage of the parallel processing capabilities and easy to modify and upgrade features of FPGA, to cope with the difficulties of...
When false alarm being occurrence non-failure product could be misdiagnose and sent to spare parts requirements so that spare parts demand rate could be overestimate, so if false alarm rate was introduced to correct the requirement the demand rate would be made more accurate. The fact is proven which demand process is still stationary when false alarm rate is constant and PALM theory is still applicable...
This paper proposes the support equipment function merging criterions based on the support function equivalent relationships and the optimization target parameter of different support equipment categories. First, the definition of equipment catalogue optimization target parameter (ECPM) is given. Then, the authors elaborate the support equipment categories merging optimization method on the base of...
The problem of how to formulate support policy with spares under the consideration of discarding is researched. In order to solve this problem, Firstly, the mathematical model is constructed, which obtains the relationship of failing number of repairable items before it discarded and the repair-discarding rate. Secondly, the repair item extreme value of failures under the consideration of discarding...
The maintenance support process of the equipment with failure prognostics is analyzed carefully in this paper. And the uncertainty factors which exist in this process are presented. Then they are separated into two groups: from the randomness and from the incomplete comprehend. The definitions of each group are given and researched in detail at the same time. And the quantitative analysis method of...
Equipment faults will produce irreversible effects for a maintenance support system. Based on the change of maintenance support resource in a maintenance support organization, maintenance support process, and external environment, the concept of maintenance support system entropy is proposed. Without considering time and cost, it is carried out from three aspects which are organizational structure...
The dynamic characteristics and the estimation method of operational availability under general mission scenarios are researched. Though the simulation method can be used to study the time-varying operational availability, it has shortage in finding and analyzing the inherent law of operational availability. According to definition, the operational availability can be derived by the supply availability...
This paper addresses the issue of determining the single item inventory level and turnaround time to make system expected backorders achieve the optimal with marginal effect analysis. First, the objective function of system expected backorders is created under cost constraint, and its characteristics are analyzed. Next, the solution to the model will be developed in two steps: for a single first-indenture...
SysML (Systems Modeling Language) is a new kind of Systems Modeling Language for Systems Engineering application. Military Aircraft Support System is a complicated system. Aiming at the insufficiency of modeling its support process, this paper attempts to build the model of support process by using SysML. Analyses support requirement of Military Aircraft by SysML Requirement Diagram Based on the Three-dimensional...
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