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The purpose of this paper is to study the effects of boundary‐layers bleeding on performance parameters of hypersonic inlets.

The inner flowfield of a hypersonic inlet at different bleeding rates is simulated with a Reynolds‐averaged Navier‐Stokes solver using a renormalization group k‐ε turbulence model.

In contrast with no bleeding, the performance parameter of hypersonic inlets without backpressure is reduced slightly, but the flow uniformity is improved. The interaction between boundary layers and shocks is weakened at the action of the bleeding, which leads to that the boundary‐layers separations at the entrance of the isolator caused by the high‐backpressure occur later, and it can improve the maximum backpressure ratio of hypersonic inlets. With the bleeding rate increasing, the maximum backpressure ratio of hypersonic inlets is added, while the total‐pressure recovery coefficient and mass‐captured coefficient are reduced.

This paper is a useful reference to the design and performance improvement of hypersonic inlets and propulsion systems.

The purpose of this paper is to provide a structured methodology to permit the optimal selection of the best‐suited computerized maintenance management system (CMMS) software within maintenance information technologies.

The analysis has been executed adopting a multi‐attribute decision‐making methodology, namely the technique for order preference by similarity to an ideal solution (TOPSIS). For the selection process, 17 criteria under five main heading have been defined. Data obtained from questionnaires and interviews with the company's maintenance managers have been used in fuzzy TOPSIS.

The application of the proposed approach allows the maintenance practitioners to concentrate on a limited subset of CMMS applications and to compare their actual capabilities in order to select the right one, rather than considering only their purchase cost.

Comparisons with other multi‐attribute decision‐making techniques such as AHP (analytic hierarchy process) and ELECTRE (elimination and choice expressing reality) under fuzzy conditions can be done for further research.

This paper is a very useful source of information both for maintenance managers and stakeholders in making decisions about the selection of CMMS software.

This paper addresses CMMS software evaluation and selection criteria for practitioners and proposes a new multi‐attribute decision‐making methodology, hierarchical fuzzy TOPSIS, for the problem.