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In this note, we study a networked system with single/multiple pinning. Given a weighted and undirected network, we derive lower and upper bounds on its algebraic connectivity with respect to the reference signal. The bounds are derived by partitioning the network in terms of distance of each node from the pinning set. Upper and lower bounds for two networks with differing topologies are computed to demonstrate the tightness of the derived results. It is shown, using the derived bounds, how requirements on the number of pinning nodes and pinning gain required for achieving stability or a specified convergence rate for the network can be easily obtained.

Motivated by the fact that the location(s) and structural properties of the pinning node(s) affect the algebraic connectivity of a network with respect to the reference value and thereby, its dynamic performance, this paper studies the application of intelligent single and multiple pinning of distributed cooperative secondary control of distributed generators (DGs) in islanded microgrid operation. It is shown that the intelligent selection of a pinning set based on the degree of connectivity and distance of leader DG(s) from the rest of the network improves the transient performance for microgrid voltage and frequency regulation. The efficacy of the distributed control strategy based on the proposed algorithms is illustrated via numerical results simulating typical scenarios for a variety of microgrid configurations., Comment: 8 pages, 11 figures, submitted to Trans. on Power Systems

Motivated by the need for the fast synchronized operation of power microgrids, we analyze the problem of single and multiple pinning in networked systems. We derive lower and upper bounds on the algebraic connectivity of the network with respect to the reference signal. These bounds are utilized to devise a suboptimal algorithm with polynomial complexity to find a suitable set of nodes to pin the network effectively and efficiently. The results are applied to secondary voltage pinning control design for a microgrid in islanded operation mode. Comparisons with existing single and multiple pinning strategies clearly demonstrate the efficacy of the obtained results.

In this paper, a robust output feedback control design is developed for suppression of aeroelastic vibration of a 2-DOF nonlinear wing section system. The aeroelastic system operates in a quasi-steady aerodynamic incompressible flowfield and is actuated using a combination of a leading-edge (LE) and a trailing-edge (TE) flap. By only utilizing measurements of pitching and plunging deflections, an innovative Lyapunov-based procedure is used to design sliding mode control inputs for the LE and TE control surface deflections. The closed-loop system is shown to have semi-global asymptotic stability even in the presence of model uncertainty and unknown external gust loading. Extensive simulation results under a variety of scenarios show the effectiveness of the control strategy.

In this paper an RFID-based localization algorithm for Internet of Things (IoT) is proposed. The responses of RFID tags to different readers are employed to determine the location of the IoT devices. The proposed algorithm does not rely on the on the unreliable power level reading and the sophisticated direction-of-arrival-based methods. First, we assume that the location of the RFID readers are known a priori. Later, in this paper, we extend our results to the scenario where neither the location of IoT devices nor the RFID readers are known. In addition, we provide analytical bounds on the number of readers in the network to have a reliable localization results. The results of the numerical experiment show a highly accurate localization of IoT devices when our proposed RF-Localize algorithm is employed.

Here, we study the ultimately bounded stability of network of mismatched systems using Lyapunov direct method. The upper bound on the error of oscillators from the center of the neighborhood is derived. Then the performance of an adaptive compensation via decentralized control is analyzed. Finally, the analytical results for a network of globally connected Lorenz oscillators are verified., 6 pages, 3 figures, Accepted and presented in IEEE Conference Allerton 2015

In this paper, a motion segmentation algorithm design is presented with the goal of segmenting a learned trajectory from demonstration such that each segment is locally maximally different from its neighbors. This segmentation is then exploited to appropriately scale (dilate/squeeze and/or rotate) a nominal trajectory learned from a few demonstrations on a fixed experimental setup such that it is applicable to different experimental settings without expanding the dataset and/or retraining the robot. The algorithm is computationally efficient in the sense that it allows facile transition between different environments. Experimental results using the Baxter robotic platform showcase the ability of the algorithm to accurately transfer a feeding task.

The effectiveness of pinning control in stabilizing a fast switching network of oscillators is examined. The minimum number of required pinning controllers is calculated under various conditions. We show that the number of required pinning controllers are inversely related to feedback gains. We also show that in some cases, these gains cannot exceed a certain limit.

In this paper, we propose a new method of signaling based on Frequency Shifted Reference (FSR) for Ultra-wideband (UWB) communication system in which the channel estimation is not required in the decoder. This signaling is more like orthogonal signaling of frequency shift keying (FSK), and has its advantage of non-coherent detection; so as a result, one of the major drawbacks of previously introduced FSR-UWB system can be eliminated. It is shown that in binary signaling the proposed method achieves similar performance as conventional Transmitted Reference UWB (TR-UWB) systems without any rate loss. Also, it is demonstrated that the proposed method outperforms the conventional FSR-UWB system in M-ary signaling for M ges 4. This way, the proposed method provides multi-rate transmission capabilities as well.