Traditional k‐out‐of‐n models assume that the components are independent, while recent research studies assume that the components are dependent caused by global load‐sharing characteristic. In this paper, we investigate the consecutive k‐out‐of‐n systems with dependent components by local load‐sharing characteristic. The work load and shock load on failed components will be equally shared by adjacent components, so the components tend to fail consecutively. Consequently, the components degradation processes may be diverse, since their degradation rate (dependent on work load) and abrupt degradation (dependent on shock load) become unequal because of local load‐sharing effect. Furthermore, the system failure will be path‐dependent on the failure sequences of components, which results in that the same system states may have different system failure probabilities. This new dependence makes the system reliability model more complex. In this work, an analytical model that can be solved numerically is derived to compute the reliability with this complex dependence. The developed model is demonstrated by a cable‐strut system in the suspension bridge. The results show that the reliability decreases significantly when the new dependence is considered.

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The efficient usage of radio resources is a major challenge in a two tier cellular network-comprised of a central macrocell underlaid with shorter range femtocell hotspots. Power optimization technique is important for radio resource management, since the deployment of femtocells may cause serious cross-tier interference and then limit overall capacity with universal frequency reuse. This paper derives an energyefficient power control scheme for an interference-limited twotier femtocell network in the analytical setting of a game theoretic framework. In the context, we present a non-cooperative power control game for a two-tier spectrum-sharing femtocell network. Specifically, in order to guarantee cellular user's Signal-toInterference-Pius-Noise Ratio(SINR) target, an algorithm is proposed that reduces transmission powers of the strongest femtocell interferers. According to the simulation results, the proposed scheme can significantly improve energy efficiency of cellular network.

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