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This paper aims to propose a new MLI topology with reduced number of switches for photovoltaic applications. Multilevel inverters (MLIs) have been found to be prospective for renewable energy applications like photovoltaic cell, as they produce output voltage from numerous separate DC sources or capacitor banks with reduced total harmonic distortion (THD) because of a staircase like waveform. However, they endure from serious setbacks including larger number of capacitors, isolated DC sources, associated gate drivers and increased control difficulty for higher number of voltage levels.

This paper proposes a new three-phase multilevel DC-link inverter topology overpowering the previously mentioned problems. The proposed topology is designed for five and seven levels in Matlab/Simulink with gating pulse using multicarrier pulse width modulation. The hardware results are shown for a five-level MLI to witness the viability of the proposed MLI for medium voltage applications.

The comparison of the proposed topology with other conventional and other topologies in terms of switch count, DC sources and power loss has been made in this paper. The reduction of switches in proposed topology results in reduced power loss. The simulation and hardware show that the output voltage yields a very close sinusoidal voltage and lesser THD.

The proposed topology can be extended for any level of output voltage which is helpful for sustainable source application.

Multilevel inverter (MLI) is a prevailing sensible alternative to two-level inverters that offer a high-quality output voltage waveform, wherein the multiple input direct current (DC) levels are established by using isolated DC sources, batteries and renewable energy sources. The purpose of this paper is to develop MLI to offer lower total harmonic distortion (THD), higher output voltage levels and reduced switching components for high power applications.

In this paper, a new tapped sources stack succored modified HX bridge MLI (TSSSMHXBMLI) topology is proposed which includes two modules, such as tapped sources stack (TSS) and modified HX bridge inverter, which perform their function in a single stage. Also, this paper outlines the formulaic implementation of the multicarrier/sub-harmonic pulse width modulation (MCPWM/SHPWM) in a Xilinx Spartan3E-500 field programmable gate array (FPGA) is suitable for the developed MLI.

The feasibility of the suggested topology is well proved by both simulation and experiment results.

This paper examines a new topology of TSSSMHXBMLI with a view to minimize total count of switching components against basic MLI topologies. The operating sequence of the suggested TSSSMHXBMLI topology is verified with the simulation study followed by an experimental investigation.

The simulation and experimental results of suggested MLI topology reveals to obtain lower THD, higher output voltage levels and reduced switching components for high power applications.

Dr. Narendran, Director, Indian Medicine (Siddha) College, has been requested by the Head of the College's Pharmacology Department to ensure intellectual protection for, and commercialisation of, a formulation that he had developed for coronary atherosclerosis. Such a request has been made for the first time in the College, and the Director has to decide how it fits into the educational and research mandate of the College. He also has with him a brief market study of the formulation's potential.

This chapter examines the manner in which a disaster-affected population of artisanal fishers relocated inland to new sites following the Indian Ocean tsunami of 2004 experienced and adapted to problems of water quality, scarcity, sanitation, and drainage. While numerous studies of conflicts over water tend to focus on issues of equitable access (see Anand, 2011), this chapter seeks to link the problem to the contested priorities driving land and resource use and access. I show how inland relocation negatively impacted households, making it harder to sustain livelihoods due to distance from the coast, while imposing new costs including that of commodified and scarce water, locational deficiencies, and the structural weaknesses of new housing. Placed in a historical context, the problem of water can be seen as an aspect of the long-term problem of ecologically unequal exchange pitting local artisanal fisher communities against an aggressively state-supported commercial fishery sector. The continuity I seek to hone in on is the pattern of imposing costs on fishers while enabling the alienation and privatization of coastal resources. Taking water not only as a vital substance presenting questions of access and quality but also as a problem of drainage and effluence enables a fuller consideration of how the unequal distribution of costs on poorer populations became legitimized in the name of recovery. At the same time, the chapter also highlights the manner in which fishers refused to remain docile subjects of power and used their agency and autonomy in adapting to and sometimes refusing the terms of relocation.

This study aims to analyze how, under the stakeholder theory, corporate social responsibility (CSR) might favor the emergence of circular economy (CE) in the Agri-food sector, which is a relevant context, as it is technologically dynamic and requires paying attention to all the stakeholders.

An exploratory, qualitative research design has been adopted to study the phenomenon in detail, as it facilitates the understanding of complex phenomena such those under investigation and helps enrich existing theory with new insights from real-world cases to add theoretical generalizations to the existing body of research in the field.

The results of this study highlight that companies adopting CSR models are oriented toward circularity.

This study provides useful indications to managers and policymakers as to how to favor the two approaches (CSR and CE) and benefit all the stakeholders.

While there is wide scholarly and managerial interest toward CSR and CE, previous research has mainly analyzed CE and CSR as two independent phenomena. Therefore, there is a lack of understanding about how the two areas are linked. Following previous studies that have started to theoretically argue an interconnection between CSR and CE, in this research, it has been empirically investigated, and further explored theoretically, whether CSR can implicitly encourage the emergence of CE approaches.

Circular supply chain management (CSCM) is proving to be a strong contributor towards sustainable development. The purpose of this study is to analyse the circular practices in CSCM implementation towards sustainability in the Indian auto sector; these practices are at the initial stage in a developing economy.

In this research work, a framework has been developed to enrich understanding of various CSCM practices for sustainability. To develop a causal framework, a Fuzzy Decision-Making Trial and Evaluation Laboratory (F-DEMATEL) methodology has been adopted.

The results produce 32 practices with cause and effect groups and their importance/priorities. Based on F-DEMATEL, these 32 practices are grouped into cause and effect groups based on R + C and R − C values.

The findings will help managers and decision-makers to gain a deeper understanding of the practices and their nature; the governmental and financial practices are identified as the most critical factors that need more attention. The results will help strategy makers to plan accordingly.

This research has identified and analysed 32 basic practices and their interrelationships to achieve sustainability in CSCM.

The purpose of this work is to study the effect of the reflow peak temperature and time above liquidus on both SnPb and SnAgCu solder joint shear strength.

Nine reflow profiles for Sn3.0Ag0.5Cu and nine reflow profiles for Sn37Pb have been developed with three levels of peak temperature (230°C, 240°C, and 250°C for Sn3.0Ag0.5Cu; and 195°C, 205°C, and 215°C for Sn37Pb) and three levels of time above solder liquidus temperature (30, 60, and 90 s). The shear force data of four different sizes of chip resistors (1206, 0805, 0603, and 0402) are compared across the different profiles. The shear forces for the resistors were measured after assembly. The fracture interfaces were inspected using scanning electron microscopy with energy dispersive spectroscopy in order to determine the failure mode and failure surface morphology.

The results show that the effects of the peak temperature and the time above solder liquidus temperature are not consistent between different component sizes and between Sn37Pb and Sn3.0Ag0.5Cu solder. The shear force of SnPb solder joints is higher than that of Sn3.0Ag0.5Cu solder joints because the wetting of SnPb is better than that of SnAgCu.

This study finds that fracture occurred partially in the termination metallization and partially in the bulk solder joint. To eliminate the effect of the termination metallization, future research is recommended to conduct the same study on solder joints without component attachment.

The shear strength of both SnPb and SnAgCu solder joints is equal to or higher than that of the termination metallization for the components tested.

Fracture was observed to occur partially in the termination metallization (Ag layer) and partially in the bulk solder joint. Therefore, it is essential to inspect the fracture interfaces when comparing solder joint shear strength.

Higher education institutions and their lecturers are strategic agents and main drivers that contribute to circular economy transition. This requires them to understand the key circular economy competencies and how to integrate circular economy holistically into their curricula with the suitable teaching and learning approaches. This study aims to support them by providing an overview on the characteristics of education for the circular economy (ECE) and suggestions to lecturers to further develop their curricula.

The data consisted of scientific articles (n = 22) describing circular economy courses in higher education. Qualitative content analysis with quantitative features was performed on the selected articles to answer the research question.

The findings confirm that the system’s focus is the key issue in ECE. However, to integrate circular economy holistically into the curricula, ECE should be implemented more widely in the context of different industries and market contexts to find innovative teaching and learning approaches. The demand side needs to be incorporated in the courses, as systemic transformation is also about transforming consumption. All levels of implementation and circular economy objectives should be included in courses to promote systems thinking. In addition, innovative forms of real workplace interaction should be increased.

As ECE has started to emerge as a new field of study, this article provides the first integrated overview of the topic.

Multilevel inverters become very popular in medium voltage applications owing to their inherent capability of reconciling stepped voltage waveform with reduced harmonic distortion and electromagnetic interference. They have several disadvantages like more number of switching devices required and devices with high voltage blocking and need additional dc sources count to engender particular voltage. So this paper aims to propose a novel tri-source symmetric cascaded multilevel inverter topology with reduced number of switching components and dc sources.

A novel multilevel inverter has been suggested in this study, offering minimal switch count in the conduction channel for the desired voltage level under symmetric and asymmetric configurations. This novel topology is optimized to prompt enormous output voltage levels by employing constant power switches count and/or dc sources of voltage. The topology claims its advantages in generating higher voltage levels with lesser number of voltage sources, gate drivers and dc voltage sources.

The consummation of the proposed arrangement is verified in Matlab/Simulink R2015b, and an experimental prototype for 7-level, 13-level, 21-level, 29-level, 25-level and 49-level operation modes is constructed to validate the simulation results.

The proposed topology operated with six new algorithms for asymmetrical configuration to propel increased number of voltage levels with reduced power components.

The purpose of this paper is to investigate the friction and wear mechanisms in copper-based self-lubricating composites with MoS₂ as the lubricating phase, which provides a theoretical basis for subsequent research on high-performance copper-based self-lubricating materials.

Friction tests were performed at a speed of 100 r/min, a load of 10 N, a friction radius of 5 mm and a sliding speed of 30 min. Friction experiments were carried out at RT-500°C. The phase composition of the samples was characterized by X-ray diffraction of Cu Ka radiation, and the microstructure, morphology and elemental distribution were characterized by scanning electron microscopy and energy dispersive spectroscopy. Reactants and valences formed during the wear process were analyzed by X-ray photoelectron spectroscopy.

The addition of MoS₂ can effectively improve friction-reducing and anti-wear action of the matrix, which is beneficial to form a lubricating film on the sliding track. After analyzing different changing mechanism of the sliding tracks, the oxides and sulfides of MoS₂, MoO₂, Cu₂O, CuO and Ni(OH)₂ were detected to form a synergetic lubricating film on the sliding track, which is responsible for the excellent tribological properties from room to elevated temperature.

For self-lubrication Cu–Sn–Ni–MoS₂ material in engineering field, there are still few available references on high-temperature application.

This paper provides a theoretical basis for the following research on copper-based self-lubricating materials with high performance.

With this statement, the authors hereby certify that the manuscript is the results of their own effort and ability. They have indicated all quotes, citations and references. Furthermore, the authors have not submitted any essay, paper or thesis with similar content elsewhere. No conflict of interest exits in the submission of this manuscript.