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The purpose of this paper is to implement a closed loop regulated bidirectional DC to DC converter for an application in the electric power system of more electric aircraft. To provide a consistent power supply to all of the electronic loads in an aircraft at the desired voltage level, good efficiency and desired transient and steady-state response, a smart and affordable DC to DC converter architecture in closed loop mode is being designed and implemented.

The aircraft electric power system (EPS) uses a bidirectional half-bridge DC to DC converter to facilitate the electric power flow from the primary power source – an AC generator installed on the aircraft engine’s shaft – to the load as well as from the secondary power source – a lithium ion battery – to the load. Rechargeable lithium ion batteries are used because they allow the primary power source to continue recharging them whenever the aircraft engine is running smoothly and because, in the event that the aircraft engine becomes overloaded during takeoff or turbulence, the charged secondary power source can step in and supply the load.

A novel nonsingular terminal sliding mode voltage controller based on exponential reaching law is used to keep the load voltage constant under any of the aforementioned circumstances, and its performance is contrasted with a tuned PI controller on the basis of their respective transient and steady-state responses. The former gives a faster and better transient and steady-state response as compared to the latter.

This research gives a novel control scheme for incorporating an auxiliary power source, i.e. rechargeable battery, in more electric aircraft EPS. The battery is so implemented that it can get regeneratively charged when primary power supply is capable of handling an additional load, i.e. the battery. The charging and discharging of the battery is carried out in closed loop mode to ensure constant battery terminal voltage, constant battery current and constant load voltage as per the requirement. A novel sliding mode controller is used to improve transient and steady-state response of the system.

Since 2020, the COVID-19 pandemic has swept the world, although the current situation is more under control. Because the development of the pandemic took place in the context of a digital society, where digital information and communication technologies (ICT) were already widely used, households certainly had to make greater use of this powerful communication tool, partly for work, and partly for distance learning purposes. It is likely that the increased use of ICT in the home, due to the lockdown, created an environment in which families were more united but also isolated and in conflict and this trend may still be present today.

This chapter is based on a study of ICT in the daily lives of Portuguese and Italian women, who lived in nuclear families, during and after the COVID pandemic. Through the testimonies of these women, therefore, we will discuss the results of the study to describe and understand how families used ICT during and after the pandemic. In particular, we are interested in answering the following questions: Did domestic spaces become more and more like work spaces due to the increased use of ICT due to the pandemic lockdown? Did distance learning, due to the lockdown, lead to an increase in ICT use by children/adolescents that is still perpetuated today?

The authors are developing a model for rural science teacher professional development, building teacher expertise and collaboration and creating high-quality science lessons: technology-mediated lesson study (TMLS).

TMLS provided the means for geographically distributed teachers to collaborate, develop, implement and improve lessons. TMLS uses technology to capture lesson implementation and collaborate on lesson iterations.

This paper describes the seven steps of the TMLS process with examples, showing how teachers develop their content and pedagogical knowledge while building relationships.

The TMLS approach provides an innovative option for teachers to collaborate across distances and form strong, lasting relationships with others.

In March 2020, the Australian Government restricted the entry of travelers into Australia by closing its international borders in an effort to contain the spread of the coronavirus (COVID-19). While Australian citizens who were resident overseas could return to Australia under certain conditions, the border closures significantly affected their ability to return to Australia and as a consequence had a dramatic impact on their lives and the lives of their families. This chapter explores the effects of the Australian government’s decision to close the national border by presenting the lived experiences of Australian citizens adversely affected by the government’s decision. The research is based on an online survey conducted in late 2021 and early 2022. Based on the findings, this chapter explores notions of Australian citizenship rights and privileges in the context of the pandemic, and the profound impacts the national lockout had on Australians as individuals, family members and on their sense of national identity. A central finding of this research reveals how citizens’ separation from family during the lockout placed considerable stress on the family as a social institution and caused significant impacts on Australians’ physical and mental health.

This chapter examines the connections between race and class divisions and examines how they shape racial inequities in the distribution of resources, power and privilege. Throughout history, racial identity has been a key factor in determining a person's position in modern capitalist societies. As such, issues of race and class have preoccupied sociologists and other scholars with diverse ideological orientations. This is highlighted in debates around the nexus of race and class in the production of racial structures, laws and institutions that legitimate and perpetuate the normalisation and centrality of whiteness. This chapter summarises some of the historical and ongoing debates, providing a synthesis of how race and class divisions continue to shape contemporary intergroup relations and social policy. It delves into racial capitalism and how race intersects with other social identities to determine socio-economic hierarchy in many western countries.

This study aims to capture how the association between a multichannel relational communication strategy (MRCS) and customer performance is contingent upon such customer performance (low- versus high-performance customers) and to reconcile past contradictory results in this marketing-related topic. To this end, the authors propose and validate the method of quantile regression as an unconventional, yet effective, means to proceed to that reconciliation.

This study collected data from 4,934 customers of a private pension fund firm and accounted for both firm- and customer-initiated relational communication channels (RCCs) and for customer lifetime value (CLV). This study estimated a generalized linear model and then a quantile regression model was used to account for customer performance heterogeneity.

This study finds that specific RCCs present different levels of association with performance for low- versus high-performance customers, where outcome customer performance is the dependent variable. For example, the relation between firm-initiated communication (FIC) and performance is stronger for low-CLV customers, whereas the relation between customer-initiated communication (CIC) and performance is increasingly stronger for high-CLV customers but not for low-CLV ones. This study also finds that combining different forms of FIC can result in a negative association with customer performance, especially for low-CLV customers.

The authors tested the conceptual model in one single firm in the specific context of financial services and with cross-sectional data, so there should be caution when extrapolating this study’s findings.

This study offers nuanced and precise managerial insights on recommended resource allocation along with relational communication efforts, showing how managers can benefit from adopting a differentiated-customer performance approach when designing their MRCS.

This study provides an overview of the state of the art of MRCS, proposes a contingency analysis of the relationship between MRCS and performance based on customer performance heterogeneity and suggests the quantile method to perform such analysis and help reconcile past contradictory findings. This study shows how the association between RCCs and CLV varies across the conditional quantiles of the distribution of customer performance. This study also addresses a recent call for a more holistic perspective on the relationships between independent and dependent variables.

This paper aims to study the application of high-tolerance and flexible indigenous bacteria and fungi, along with the co-metabolism in recycled paper and cardboard mill (RPCM) wastewater treatment (WWT).

The molecular characterization of isolated indigenous bacteria and fungi was performed by 16S rRNA and 18S rRNA gene sequencing, respectively. Glucose was used as a cometabolic substrate to enhance the bioremediation process.

The highest removal efficiency was achieved for both chemical oxygen demand (COD) and color [78% COD and 45% color removal by Pseudomonas aeruginosa RW-2 (MZ603673), as well as approximately 70% COD and 48% color removal by Geotrichum candidum RW-4 (ON024394)]. The corresponding percentages were higher in comparison with the efficiency obtained from the oxidation ditch unit in the full-scale RPCM WWT plant.

Indigenous P. aeruginosa RW-2 and G. candidum RW-4 demonstrated effective capability in RPCM WWT despite the highly toxic and low biodegradable nature, especially with the assistance of glucose.

Plasma technology has become of great interest in a wide variety of industrial and domestic applications. Moreover, the application of plasma in the domestic field has increased in recent years due to its applications to surface treatment and disinfection. In this context, there is a significant need for versatile power generators able to generate a wide range of output voltage/current ranging from direct current (DC) to tens of kHz in the range of kVs. The purpose of this paper is to develop a highly versatile power converter for plasma generation based on a multilevel topology.

This paper proposes a versatile multilevel topology able to generate versatile output waveforms. The followed methodology includes simulation of the proposed architecture, design of the power electronics, control and magnetic elements and test laboratory tests after building an eight-level prototype.

The proposed converter has been designed and tested using an experimental prototype. The designed generator is able to operate at 10 kVpp output voltage and 10 kHz, proving the feasibility of the proposed approach.

The proposed converter enables versatile waveform generation, enabling advanced studies in plasma generation. Unlike previous proposals, the proposed converter features bidirectional operation, allowing to test complex reactive loads. Besides, complex waveforms can be generated, allowing testing complex patterns for optimized cold-plasma generation methods. Besides, unlike transformer- or resonant-network-based approaches, the proposed generator features very low output impedance regardless the operating point, exhibiting improved and reliable performance for different operating conditions.

This study aims to analyze the effects of the components of absorptive capacity (ACAP) – potential absorptive capacity (PACAP) and realized absorptive capacity (RACAP) on inbound and outbound open innovation (OI). In addition, this study investigates the moderating role that knowledge-oriented leadership (KOL) plays in the relationship between ACAP and OI.

This research adopts a quantitative approach, using structural equation modeling, in a sample of 218 companies in the Brazilian manufacturing sector, using a random sampling technique and self-administered questionnaire.

The results indicate that while PACAP positively influences inbound and outbound OI, RACAP has a significant relationship only with outbound OI. In addition, KOL moderates the significant relationships between PACAP and RACAP and OI, indicating that the development of a leadership that fosters learning and interaction between employees and sectors of the organization impacts the innovation results of companies in the manufacturing sector.

This study also shows that managers must have an active role in the construction of an organizational context that supports learning through initiatives that encourage the process of trial and error, teamwork and cooperation between employees.

This research advances previous studies by relating the two components of ACAP (PACAP and RACAP) with the two OI models (inbound and outbound), in addition to analyzing the moderating role that KOL plays in this relationship between ACAP and OI.