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Recently the integration of renewable energy resources to direct-current microgrids has become a hot research topic. The voltage stability problem is of paramount importance when the system is subject to external disturbances, parameters uncertainties, and plug-and-play regimes. This paper introduces a novel decentralized voltage tracking for a direct-current islanded microgrid. It consists of numerous Distributed Generation units. The decentralized controller of each distributed generator adjusts the voltage at the point of common coupling to track the desired reference. The proposed control copes with the plug-and-play operation of the microgrid. This means that the possibility of connection/disconnection distributed generators without deteriorating the stability of the overall microgrid is done through the invariant ellipsoid set and the linear matrix inequality optimization. Another merit of the proposed control is that updating the rest of the controllers is not required when a distributed generator is plugged in or out. Moreover, the proposed decentralized controller just uses local states (information) of its distributed generator only. Many simulations and practical studies with different scenarios have been conducted in this paper to verify the performance of the proposed controllers. Comparison with the existing schemes is included.

The recent race for autonomous or `driverless' vehicles, has spawned a lot of research in the area of Internet of Autonomous Vehicles (IAVs). With the advent of the latest technology fueled by Artificial Intelligence and Machine Learning, Autonomous Vehicles (AVs) can now determine the best possible route to a destination based on the current traffic situation and take dynamic driving decisions accordingly, while preventing accidents. Field trials for single autonomous vehicles have been largely successful. However, as more autonomous vehicles will be added to the intelligent transport networks, current research is now centered around their synergistic coexistence in the offering of network-centric and user-centric services. This development is governed by borrowing several concepts from the legacy Internet to address the problems of IAVs. In this paper, we present an extensive overview of the research challenges in the IAVs. Moreover, our contributions in this paper are that (i) We show how the network-oriented cooperative client-server model will give way to a more unorthodox and `selfish' decentralized and peer-to-peer (P2P) model, for example in the offering of navigation services on the IAV. (ii) We discuss how centralized architecture will give way to more distributed architectures for real-time information propagation over the IAV. (iii) We discuss how network-centric policies will begin to shift to user-centric under more beneficial revenue models by offering network-assisted quality of service (QoS) provisioning. (iv) We discuss in detail how vehicle traffic grooming in the IAV would present as much of a challenge as in the legacy Internet. (v) We discuss the disruptive role of value-added services on the IAV, and (iv) Finally, we discuss the problem of cyber threats in the IAV just as in the legacy Internet.

Decoupling between axial and transversal forces is an essential during tool-tissue interaction in many medicine surgeries; in particular where fine and precise manipulation is required to save the delicate tissues. One example of which is the vitreoretinal microsurgery (VRMS). When fiber Bragg grating based sensing technique is utilized, the cross-talk noise between the axial and transversal forces always show up severely due to its conventional wavelength shift method. To address the challenge, we have introduced theoretical method in which a combination of tapered FBG (TFBG) and bandwidth modulation method instead are used. Here in this paper, first phase of our ongoing progress to proof the concept and validate the simulation results is demonstrated experimentally. We have developed a prototype incorporated TFBG mimicking the structure of the ophthalmia's needle to measure temperature-insensitive 1-DOF axial forces. High speed plug and play (I-MON-256USB (Ibsen)) is used to monitor the reflection spectrum of the prototype sensor. An automated calibration system using LabVIEW with efficient algorithms have been developed to calculate and keep track the bandwidth variations as different values of axial forces applied. Calibration procedures are repeated three times to validate the consistency of the sensor response. Experimental results show that, the estimated force values of our prototype are consistent with their actual values with RMS error less than 0.356 N over the range (1N-10N), while temperature insensitivity is guaranteed.

The industrial cyber-physical system enables collaboration between distributed nodes across industrial clouds and edge devices. Flexibility and interoperability could be enhanced significantly by introducing the service-oriented architecture to industrial edge devices. From the industrial edge computing perspective, software components shall be dynamically composed across heterogeneous edge devices to perform various functionalities. In this paper, a knowledge-driven Microservice-based architecture to enable plug-and-play software components is proposed for industrial edges. These software components can be dynamically configured based on the orchestration of microservices with the support of the knowledge base and the reasoning process. These semantically enhanced plug-and-play microservices could provide rapid online reconfiguration without any programming efforts. The use of the plug-and-play software components is demonstrated by an assembly line example.

Changes in distribution grids pose significant challenges with respect to the control and management of these grids. Stability and decentralized control are vital to ensure the availability and accessibility of plug-and-play dc distribution grids that are (temporarily) without communication. Therefore, this paper presents guidelines for these grids that ensure global stability and a decentralized control strategy that implements these stability guidelines. The stability guidelines are derived using a Brayton-Moser representation of the system to arrive at a Lyapunov candidate function. Furthermore, the decentralized control strategy implements these stability guidelines and ensures that the voltages in the system remain within a specified range. Additionally, several simulations are performed to illustrate the stability of the system and the behavior of the control strategy under different scenarios.