New cascaded multilevel inverter with series connection of novel capacitor based basic units

Abstract This research proposes a novel multilevel inverter based on a new capacitor basic unit. Four capacitors are deployed in this unit to provide both even and odd voltage levels. Two‐cell proposed cascaded multilevel inverters and developed cascaded multilevel inverters are evaluated in order to improve the number of output levels generated. Calculations are made for all associated equations after determining the value of the necessary DC voltage source. Additionally, both inverters' switching tables and capacitor charge and discharge modes are fully explained. The merits and disadvantages of the proposed topology are then assessed by contrasting the cascaded multilevel inverter under consideration with a number of widely used multilevel inverters. The key benefit of the suggested architecture is the increase in the number of output levels produced while using fewer power electronic devices and DC voltage sources overall. The proposed one‐cell cascaded inverter is then utilized to evaluate the performance of the proposed topology using the relevant equations, simulations, and experimental data. The simulation is carried out using the EMTDC/PSCAD software, and a lab prototype yields the experimental data

Contribution of health researches in national knowledge production: A scientometrics study on 15-year research products of Iran

Background: Researchers, practitioners, and policymakers call for updated valid evidence to monitor, prevent, and control of alarming trends of health problems. To respond to these needs, health researches provide the vast multidisciplinary scientific fields. We quantify the national trends of health research outputs and its contribution in total science products. Methods: We systematically searched Scopus database with the most coverage in health and biomedicine discipline as the only sources for multidisciplinary citation reports, for all total and health-related publications, from 2000 to 2014. These scientometrics analyses covered the trends of main index of scientific products, citations, and collaborative papers. We also provided information on top institutions, journals, and collaborative research centers in the fields of health researches. Results: In Iran, over a 15-year period, 237,056 scientific papers have been published, of which 81,867 (34.53%) were assigned to health-related fields. Pearson's Chi-square test showed significant time trends between published papers and their citations. Tehran University of Medical Sciences was responsible for 21.87% of knowledge productions share. The second and the third ranks with 11.15% and 7.28% belonged to Azad University and Shahid Beheshti University of Medical Sciences, respectively. In total fields, Iran had the most collaborative papers with the USA (4.17%), the UK (2.41%), and Canada (0.02%). In health-related papers, similar patterns of collaboration followed by 4.75%, 2.77%, and 1.93% of papers. Conclusions: Despite the ascending trends in health research outputs, more efforts required for the promotion of collaborative outputs that cause synergy of resources and the use of practical results. These analyses also could be useful for better planning and management of planning and conducting studies in these fields