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Concerns over environment and increased demand of energy have led the world to think about alternate energy sources such as wind, hydro, solar and fuel cells. Out of these, photovoltaic (PV) power generation systems have become increasingly important all over the world due its availability, cleanness, low maintenance cost and inexhaustible nature. But power produced by the photovoltaic system is stochastic in nature due to the variation of solar irradiation and cell temperature throughout the day. In order to track the varying power, a DC-DC converter with maximum power point tracker (MPPT) is used. Different MPPT algorithms have been proposed for tracking peak power from the PV panel. Selection of adequate DC-DC converter is also an important factor since it has an influence on overall performance of the PV system. This paper presents a comparative study on the characteristics of different non-isolated DC-DC converters and highlights the various research works that has been done on DC-DC converters based MPPT PV system. Study shows that selection of converter also has an impact on the overall performance of the PV system. Based on the survey and comparative study, selection criteria to choose DC-DC converter for PV system is described in this paper. [ABSTRACT FROM AUTHOR]

In this paper, a detailed modelling and analysis of a switched inductor (SI)-based improved single-ended primary inductor converter (SEPIC) has been presented. To increase the gain of conventional SEPIC converter, input and output side inductors are replaced with SI structures. Design and stability analysis for continuous conduction mode operation of the proposed SI-SEPIC converter has also been presented in this paper. State space averaging technique is used to model the converter and carry out the stability analysis. Performance and stability analysis of closed loop configuration is predicted by observing the open loop behaviour using Nyquist diagram and Nichols chart. System was found to stable and critically damped. [ABSTRACT FROM AUTHOR]

Metal/metal oxide nanocomposites (NCs) have been attracting significant attention in recent times because of their applications in the fields of energy and environment. In the present work, we investigate the photocatalytic and electrochemical performances of Ni/NiO NCs synthesized by a facile and cost-effective reduction method using lithium salt as the dopant. Lithium influences the size, morphology and structural constitution of the final product. A variation in the lithium percentage was seen to have a direct effect on the Ni content. The structural conformation of the samples has been analyzed by XRD and further confirmed by XPS. A low optical energy bandgap (∼3.7 eV) and a mesoporous structure of the as-prepared samples were seen to play a crucial role in achieving the photocatalytic degradation of the cationic organic dyes concomitant to its electrochemical activity. On illumination with UV light, the Li-doped Ni/NiO NCs demonstrated rapid degradation of crystal violet and methyl violet 2B dyes. The synergism arising due to the substitutional doping of lithium and the presence of metallic nickel leads to efficient photodegradation of the dye pollutants by the catalysts. Further, the Li-doped Ni/NiO NCs displayed a better electrochemical performance than the undoped samples. The NC with 1 wt% Li exhibited the best values of specific capacitance (276.2 F g−1 at 5 A g−1) with an excellent cycling ability (<1% capacitance loss after 2000 cycles). The enhanced electrochemical and photocatalytic results suggest the dual activity of these nanocomposites in energy storage and water treatment applications. [ABSTRACT FROM AUTHOR]

An abstract of the article "Evaluation of the Clinical Outcomes in Patients With COPD Who Undergo Structured and Supervised Pulmonary Rehabilitation in a Tertiary Care Centre in South India" by Dileep Kumar, Arjun Padmanabhan, and Ameer Azeez is presented.

The study aims to study the customer retention in organization with special reference to banking industry. The results revealed that, to maintain existing customers is becoming more and more important. The reason for this development is based on the knowledge that long term related customers compare various offers against each other and choose the best one. Many reasons are identified as most important reasons for customer defection in a given service industry like banking, but the prominence of each factor depends upon the situation prevailing in each banking organization. The study suggests that, as consumer remains satisfied with a bank, they spread a positive word of mouth, which is very effective in case of services for attracting new customers. Longer the customer stays with a bank, the bank knows more about him, which enables it to offer customized services which make it difficult for the customer to defect. This may even provide opportunities to the bank to charge price premium by offering individualized services which may be difficult for the competitors to offer. Customer retention should be implemented in every organization/company. There exists a broad pallet of various instruments which can have a lasting effect. The earlier a company start with professional customer retention the faster first results can be experienced. [ABSTRACT FROM AUTHOR]

The advent of COVID-19 has kept the whole world on their toes. Countries are maximizing their efforts to combat the virus and to minimize the infection. Since infectious microorganisms may be transmitted by variety of routes, respiratory and facial protection is required for those that are usually transmitted via droplets/aerosols. Therefore this pandemic has caused a sudden increase in the demand for personal protective equipment (PPE) such as gloves, masks, and many other important items since, the evidence of individual-to-individual transmission (through respiratory droplets/coughing) and secondary infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). But the disposal of these personal protective measures remains a huge question mark towards the environmental impact. Huge waste generation demands proper segregation according to waste types, collection, and recycling to minimize the risk of infection spread through aerosols and attempts to implement measures to monitor infections. Hence, this review focuses on the impact of environment due to improper disposal of these personal protective measures and to investigate the safe disposal methods for these protective measures by using the safe, secure and innovative biological methods such as the use of Artificial Intelligence (AI) and Ultraviolet (UV) lights for killing such deadly viruses. • Countries are maximizing their efforts to combat the virus and minimize infection. • The PPM is hugely by the healthcare professionals as well as common man. • Disposal of these PPM remains huge question mark towards environmental impact. • Safe disposal of these PPM by using the safe and secure biological methods. [ABSTRACT FROM AUTHOR]