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Maintaining the distribution power substation's health and reliability has been an issue for many years. A typical transformer measurement device detects only one transformer characteristic, such as power, current, voltage, or phase. While some methods can detect several factors, the acquisition time and operation parameters are too long, and the testing speed is insufficient. However, a monitoring system that can check the temperature level of the transformer continuously and predict faults such as overheating, overcurrent, after which the fault diagnosis is relayed to the base station through a GSM modem is developed in this paper. After receiving the message of any abnormality remedial action can be taken immediately to prevent any catastrophic failures of distribution transformers. Key components used in this development are the ATmega328 microcontroller, the GSM modem, the LM35 temperature sensor, ACS712 current sensor, and so on. The GSM-based monitoring of the distribution transformer is preferable to manual monitoring since it is not always possible to monitor the ambient temperature rise, load current manually.

Centralized file-sharing networks have low reliability, scalability issues, and possess a single point of failure, thus making peer-to-peer (P2P) networks an attractive alternative since they are mostly anonymous, autonomous, cooperative, and decentralized. Although, there are review articles on P2P overlay networks and technologies, however, other aspects such as hybrid P2P networks, modelling of P2P, trust and reputation management issues, coexistence with other existing networks, and so on have not been comprehensively reviewed. In addition, existing reviews were limited to articles published in or before 2012. This paper performs a state-of-the-art literature survey on the emerging research areas of P2P networks, applications and ensuing challenges along with proposed solutions by scholars. The literature search for this survey was limited to the top-rated publisher of scholarly articles. This research shows that issues with security, privacy, the confidentiality of information and trust management will need greater attention, especially in sensitive applications like health services and vehicle to vehicle communication ad hoc networks. In addition, more work is needed in developing solutions to effectively investigate and curb deviant behaviours among some P2P networks.

The

Abstract-properties of Silicon Carbide Junction Field EffectTransistor (SiC JFET) such as high switching speed, low forward voltage drop and high temperature operation have attracted the interest of power electronic researchers and technologists, who for many years developed devices based on Silicon (Si). A number of power system Engineers have made efforts to develop more robust equipment including circuits or modules with higher power density. However, it was realized that several available power semiconductor devices were approaching theoretical limits offered by Si material with respect to capability to block high voltage, provide low on-state voltage drop and switch at high frequencies. This paper presents an overview of the current applications of SiC JFET in circuits such as inverters, rectifiers and amplifiers. Other areas of application reviewed include; usage of the SiC JFET in pulse signal circuits and boost converters. Efforts directed toward mitigating the observed increase in electromagnetic interference were also discussed. It also presented some areas for further research, such as having more applications of SiC JFET in harsh, high temperature environment. More work is needed with regards to SiC JFET drivers so as to ensure stable and reliable operation, and reduction in the prices of SiC JFETs through mass production by industries.