This paper presents an application of information theory to identify sets of key players in social networks. First, we define two entropy measures that we use to analyze the structural properties of a social network. Then, we propose a new method aimed at finding a set of key players that solves the KPP-Neg and KPP-Pos problems. Our preliminary experimental results indicate that the entropy measures can be used effectively to identify a set of key players in a social network.

DAC is a linear control technique used to mitigate the effect of disturbance on the plant. It is a superposition of full state feedback and disturbance feedback. This paper presents a control technique based on Disturbance Accommodation Control (DAC) to reduce fatigue on drive train generated by wind which is combination of step and periodic disturbances (generated by wind shear and tower shadow ) of the turbine for above rated wind speed (Region III). We have presented a wind modeling for wind shear and tower shadow effect for the wind turbine control simulation and also developed a control scheme to mitigate the effect of 3p flicker on drive train. 5MW wind turbine of the National Renewable Laboratories (NREL) is used as research object and results are simulated in MATLAB/Simulink. We designed the controller based on linearized model of the wind turbine generated for above rated wind speed and then tested its performance on the nonlinear model of wind turbine. We have shown a comparison of the results for proportional-integral(PI) and proposed DAC controller tested on nonlinear model of wind turbine. Result shows that our proposed controller shows better mitigation of flicker generated due to 3p effect by using collective pitch control as compared to PI with tower and actuator dynamics.

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In today's internet-of-things (IoT) environment, wireless sensor networks (WSNs) have many advantages, with broad applications in different areas including environmental monitoring, maintaining security, etc. However, high energy depletion may lead to node failures in WSNs. In most WSNs, nodes deplete energy mainly because of the flooding and broadcasting of route-request (RREQ) packets, which is essential for route discovery in WSNs. The present article models wireless sensor networks as software-defined wireless sensor networks (SD-WSNs) where the network is divided into multiple clusters or zones, and each zone is controlled by a software-defined network (SDN) controller. The SDN controller is aware of the topology of each zone, and finds out the optimum energy efficient path from any source to any destination inside the zone. For destinations outside of the zone, the SDN controller of the source zone instructs the source to send a message to all of the peripheral nodes in that zone, so that they can forward the message to the peripheral nodes in other zones, and the process goes on until a destination is found. As far as energy-efficient path selection is concerned, the SDN controller of a zone is aware of the connectivity and residual energy of each node. Therefore, it is capable of discovering an optimum energy efficient path from any source to any destination inside as well as outside of the zone of the source. Accordingly, flow tables in different routers are updated dynamically. The task of route discovery is shifted from individual nodes to controllers, and as a result, the flooding of route-requests is completely eliminated. Software-defined energy aware routing (SD-EAR)also proposes an innovative sleeping strategy where exhausted nodes are allowed to go to sleep through a sleep request-sleep grant mechanism. All of these result in huge energy savings in SD-WSN, as shown in the simulation results.