Repair limit policy of aircraft component based on extended uncertain random renewal reward process

PurposeThe purpose of this paper is to focus on an optimizing maintenance policy with repair limit time for a new type of aircraft component, in which the lifetime is assumed to be an uncertain variable due to no historical operation data, and the repair time is a random variable that can be described by the experimental data.Design/methodology/approachTo describe this repair limit time policy over an infinite time horizon, an extended uncertain random renewal reward theorem is firstly proposed based on chance theory, involves uncertain random interarrival times and stochastic rewards. Accordingly, the uncertain random programming model, which minimized the expected maintenance cost rate, is formulated to find the optimal repair limit time.FindingsA numerical example with sensitivity analysis is provided to illustrate the utility of the proposed policy. It provides a useful reference and guidance for aircraft optimization. For maintainers, it plays an important guiding role in engineering practice.Originality/valueThe proposed uncertain random renewal reward process proved useful for the optimization of maintenance strategy with maintenance limited time for a new type of aircraft components, which provides scientific support for aircraft maintenance decision-making for civil aviation enterprises.

Reward and emotion in the brain

Pleasure and reward are central for motivation, learning, feeling and allostasis. Although reward is without any doubt an affective phenomenon, there is no consensus concerning its relationship with emotion. In this mini-review we discuss this conceptual issue both from the perspective of theories of reward and emotion as well as human systems neuroimaging. We first describe how the reward process can be understood and dissected as intertwined with the emotion process, in particular in light of the appraisal theories, and then discuss how different facets of the reward process can be studied using neuroimaging and neurostimulation techniques. We conclude that future work needs to focus on mapping the similarities and differences across stimuli and processes that lead to pleasures and rewards and propose that an integrative affective sciences approach would provide means for studying the emotional nature of reward.

An Uncertain Alternating Renewal Insurance Risk Model

The claim process in an insurance risk model with uncertainty is traditionally described by an uncertain renewal reward process. However, the claim process actually includes two processes, which are called the report process and the payment process, respectively. An alternative way is to describe the claim process by an uncertain alternating renewal reward process. Therefore, this paper proposes an insurance risk model under uncertain measure in which the claim process is supposed to be an alternating renewal reward process and the premium process is regarded as a renewal reward process. Then, the paper also gives the inverse uncertainty distribution of the insurance risk process. The expression of ruin index and the uncertainty distribution of the ruin time are derived which both have explicit expressions based on given uncertainty distributions. Finally, several examples are provided to illustrate the modeling ideas.

Ernst Denert Software Engineering Awards 2019

The need to improve software engineering practices is continuously rising and software development practitioners are highly interested in improving their software systems and the methods to build them. And well, software engineering research has numerous success stories. The Ernst Denert Software Engineering Award specifically rewards researchers that value the practical impact of their work and aim to improve current software engineering practices. This chapter summarizes the awards history as well as the current reward process and criteria.