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In recent times, the growing adoption of transformer-less grid connected PV inverter has sparked interest in exploring topologies aimed at reducing leakage current. The leakage current from a photovoltaic panel and utility grid leads to harmonics and system losses. A new structure for single stage inverter with three switches, common ground and switched inductor is presented and analyzed. The proposed inverter features reduced leakage current and improved gain, high efficiency and low stress on semiconductor devices. This topology enables step up operation of input voltage, minimizing leakage currents is achieved by connecting a common terminal between the grid and the input, ensuring low levels of electrical leakage. The proposed converter offers several benefits, including a common grounding system, effective reduction of leakage current, and enhanced efficiency due to the utilization of just three active switches. This versatile topology makes it an ideal choice for our needs. A detailed analysis of the operational principles and steady-state characteristics of the inverter has been thoroughly examined. The inverter was simulated using MATLAB/SIMULINK R2021b, hinting that the inverter achieves a peak efficiency of 89%. Subsequently, a hardware prototype was developed and implemented using dSPACE. The experimental outcomes derived from a prototype of the inverter validate the theoretical assumptions and align with the results obtained from simulations. [ABSTRACT FROM AUTHOR]

Dye doped crystals have attracted researchers in the framework of crystal growth because of its wide range of applications in biomedical, electrical, and optical devices. 0.1 M of Zinc sulphate doped with Rh.B dye single crystals were grown using slow evaporation method at room temperature. The synthesized crystals were characterized using UV– visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), X-ray Diffraction (XRD), Dielectric, A.C conductivity and Micro hardness. Fourier transform infrared spectroscopy revealed a strong peak about 438 cm−1 corresponding to Zn stretching vibration, and strong PL emission spectra indicate highly optically active material. XRD patterns were well matched with standard JCPDS files, providing structural details. XRD pattern revealed the synthesized crystals are monoclinic in nature. The presence of Zn and other dye constituents are investigated using EDX. With increasing temperature and frequency, the dielectric constant values raise. And also the crystals were examined against Gram negative bacteria E.coli to study the antibacterial activity. [ABSTRACT FROM AUTHOR]

In order to satisfy the demand for basic resources for the enormously expanding population, it is of prime importance to sustainably use and augment the natural resources. Of all the natural resources, water plays a major role for survival of life on our planet. Since there is an exponential increase in demand of water for various purposes such as agriculture, domestic and industries, it is necessary to map out and optimally utilize the water resource. As the surface water alone is not enough to fulfil the growing demands of the people, groundwater is extracted and is being used by the community on a large scale. For the sustainable use of groundwater, it is necessary to carry out groundwater assessment to know how much water is available for extraction and the stage of groundwater potential development. In this study, an attempt is made to assess the groundwater potential of five blocks of Kancheepuram district using water level fluctuation method based on GEC norms 2015, for the period 2010-2019. The population of the five blocks was forecast for the study period using geometric increase method. The stage of groundwater development in 2010, which fell in safe and semi critical categories, changed to semi critical and critical categories respectively in the year 2019, due to over extraction of groundwater resource. The rainfall departure analysis, % contribution of seasonal rainfall to annual rainfall has been performed to compare with the groundwater recharge. The north west monsoon contributed 51% of the annual rainfall, hence by considering the amount of rainfall in the peak season, suitable recharge structure is suggested for the blocks under consideration. [ABSTRACT FROM AUTHOR]

This paper discusses the designing, implementation and testing of an Autonomous Underwater Vehicle (AUV) robot, which travels underwater to detect possible human presence. This robot is expected to be extremely useful in human rescue operations during water accidents. The AUV is deployed above the water surface, near to the approximate target location and it swims underwater, checking for the target (human body), in real time. Once the target is detected, the AUV locks the targets position and move towards the target to verify and make a decision: whether it is a human body or not. After the confirmation, the robot swims back vertically up to the water surface, from where it can be easily noticed by the ground rescue crew. The diver can then dive there, to find the human body. Alternately, an air bag could also be inflated after locking it to the target, which will float back to the surface carrying the target. This technology is very helpful for underwater human detection since we need not have to search the whole water body and hence both time and resources are saved. [ABSTRACT FROM AUTHOR]