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We study multi-hop broadcast in wireless networks with one source node and multiple receiving nodes. The message flow from the source to the receivers can be modeled as a tree-graph, called broadcast-tree. The problem of finding the minimum-power broadcast-tree (MPBT) is NP-complete.Unlike most of the existing centralized approaches, we propose a decentralized algorithm, based on a non-cooperative cost-sharing game. In this game, every receiving node, as a player, chooses another node of the network as its respective transmitting node for receiving the message. Consequently, a cost is assigned to the receiving node based on the power imposed on its chosen transmitting node.In our model, the total required power at a transmitting node consists of (i) the transmit power and (ii) the circuitry power needed for communication hardware modules. We develop our algorithm using the marginal contribution (MC) cost-sharing scheme and show that it is the only scheme by which the optimum broadcast-tree is always a Nash equilibrium (NE) of the game. Simulation results demonstrate that our proposed algorithm outperforms conventional algorithms for the MPBT problem. Besides, we show that the circuitry power, which is usually ignored by existing algorithms, significantly impacts the energy-efficiency of the network. Index TermsEnergy-efficiency; minimum-power multi-hop broadcast; potential game; optimization. is disseminated through the network with the help of some intermediate nodes which re-transmit the message. This problem is known as the minimum-power broadcast-tree (MPBT) problem since the connections between the source and the receiving nodes form a tree-graph rooted at the source, called the broadcast-tree [1]. MPBT construction has been studied by researchers extensively during the past two decades [1][2][3][4][5][6][7][8][9][10][11][12]. NP-completeness of the MPBT can be shown by reducing the Steiner tree problem to it [13]. This means that a polynomial-time algorithm to find the optimum broadcast-tree unlikely exists. Although many algorithms have been proposed for the MPBT problem, most of them are centralized heuristics [1-6]. Since multi-hop device-todevice communication is seen as a promising technique for improving the capacity of 5G cellular networks [14] and due to the variety of its applications, e.g., video streaming [15], vehicular communications [16], etc., it is vital to revisit the MPBT problem to find a decentralized yet efficient algorithm for it.Seeing the MPBT problem from a decentralized optimization point of view, every individual node has to play its own role in forming the broadcast-tree by establishing a communication link to another node. This can be suitably modeled by game theory, in which the players of the game, here the nodes, are typically modeled as selfish agents seeking to minimize (maximize) their own cost (revenue). In our work, the action of a node is to choose another node in the network as its respective transmitting node to receive the source's message from. As a consequence of i...

Objective.The present study aims to evaluate the effectiveness of cognitive behavioral therapy (CBT) and spiritual-religious intervention in improvement coping responses and quality of life among women surviving from breast cancer.Methods.This was a semi-experimental study. Forty-five breast cancer survivor referred to cancer research center at Shahid Beheshti university of medical Sciences in Tehran, assigned in 3 groups randomly (CBT group, spiritual-religious group and control group). The interventions were eight sessions cognitive-behavioral therapy and spiritual-religious intervention. The participants were evaluated through quality of life questionnaire published by european organization for research and treatment of cancer (QLQ-30C-ver3) and coping responses inventory (CRI). The data were analyzed using covariance.Finding.Although both intervention groups improved in coping and quality of life, it was not statistically significant(P < 0.08).Conclusion.Although both intervention groups improved in coping and quality of life but there is no differences between two groups.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Disturbance rejection strategies are very useful for the robustness improvement of the predictive control method. But they can only be used in the modulated-based predictive control methods such as continuous set model predictive control (CS-MPC) and deadbeat control. This paper presents a robust current prediction model based on total disturbance observer (TDO), which is applicable in the finite set model predictive current control (FS-MPCC). In the proposed method, the disturbance is directly used as a part of the prediction model instead of the disturbance rejection loop. So, the proposed method has two advantages over the disturbance rejection-based CS-MPC schemes. The first advantage is no need for a controller, which is an essential part of the disturbance rejection-based CS-MPC. Therefore, the proposed method is simpler and has fewer control parameters. The second feature is that the proposed model is in the stationary frame. In this way, the frame transformation is avoided in the prediction model. Moreover, to guarantee zero steady-state error in the current prediction model, this paper proposes a complete designing process for TDO based on the convergence analysis. The performance of the proposed control system is evaluated through simulations and experimental tests.

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