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Introduction: Aspects of power system protection which contributes to mal-operations and blackouts can be improved by supervision of system behavior and response based analysis rather than condition-based or event-based analysis using wide area measurements based on synchrophasor technology. The paper explores the application of micro-Phasor Measurement Unit for time synchronized real-time distribution network monitoring and agile decision support schemes for system prognosis and control. Case description: The scheme is proposed as part of a project on "Power System Voltage Stability Analysis using synchrophasors in Distribution System of Kerala Grid" at Kerala State Electricity Board Ltd. An actual grid occurrence during the severe tropical cyclone Ockhi, is considered as the base case which motivated the work. Discussion and evaluation: A voltage stability index (VSI) based special protection scheme (SPS) for radial distribution network at a proposed smart city is presented in the present study. The proposed special protection scheme on actual implementation can use data from proposed local micro-Phasor Measurement Unit. The PMU is proposed to be placed at one of the key nodes of the distribution system network in the city. Conclusion: The VSI is derived using local phasor values and is used to initiate a Special Protection Scheme for N-1 contingency at the key node, so as to ensure availability of the most essential feeder which provides supply to a hospital campus housing several health institutes of prime importance. The voltage stability index derived is tested and SPS is validated using real-time grid data.

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<span>In this paper cost function and reliability analysis of classic novel symmetric multilevel inverter topology has been presented. Cost function and reliability analysis are the economical factors of the effieciency of an inverter, this made the intrest in this area.cost function deneotes the cost of the inverter based on the power flow, reliability explain the mean time failure propotional to the life span. Firstly the cost function of the novel topology has been proposed using mathematical calculation using various current rating and the results are validated compared with exiting topology.   Secondly reliability approach is used to evaluate the reliability of the switch with respect to the failure rate and mean time period of the switch using fedis and markow reliability analysis equations and the results are evaluated for all the switches present in the topology. And the results are the compared with the conventional multilevel inverter, cost function and reliability analysis of the proposed multilevel inverter.</span>

The word Ecosystem' stems from the Greek word 'Oikos', meaning 'Home' and 'systema' or 'System'. This word was proposed by British ecologist A.G. Tansley (1935). Thus ecosystem is a biological community of interacting organisms within their physical and chemical environment. Ecosystem embodies the terrestrial ecosystemswhere the organism and their environment interact on landmasses and Aquatic Ecosystems-where plants, animals and their physical environment interact in water. The aquatic Ecosystem-The Wonderland ! The Aquatic Ecosystem is located in the body of water. Mutually dependent communities of Organisms live in the Aquatic Ecosystems. Aquatic Ecosystem are of 2 types :i) Marine Ecosystem ii) Freshwater Ecosystem