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This study aims to examine the effect of asymmetric aging (120 and 270 degrees) and symmetrical aging on the performance of silicone rubber insulators. The effects of different aged surfaces, pollution levels and humidity on flashover voltage (FV) have been experimentally investigated. Based on the laboratory results, a mathematical model has been presented to estimate the FV of insulators.

According to insulators constituent materials, polymer insulators are affected by environmental conditions, specifically by ultraviolet (UV) radiation. To investigate the effect of aging and environmental conditions on the insulator, two types of silicone rubber insulators were aged under UV radiation. Environmental conditions have been created by changing humidity in five levels and pollution in three levels. All tests have been performed on two virgins, two full aged and four asymmetric-aged insulators. Also, according to the effect of each parameter on the FV, a mathematical model has been presented for it.

UV aging causes the destruction of the silicon rubber insulator. The occurrence of flashover is one of the consequences of insulation failure. The enlargement of the aged surface has a nonlinear relationship with the reduction of the FV. By considering the effect of the aged surface, the accuracy of FV modeling can be increased. The results obtained from the mathematical model have shown that the estimation of the FV in different environmental conditions has an error of less than 5%. However, the modeling error is more than 15% if the effect of the aged surface is not considered.

In this work, it is intended to investigate the effect of asymmetric aging on the FV of the insulator. The obtained results have shown that the asymmetric aging surface is an important factor in changing the harmonic components of the leakage current, condition monitoring indicators and FV.

Social disclosure is a vital tool that can help organizations in developing economies, including Nigeria, measure and manage their social impacts and performances. This could help in achieving sustainable development goals and enhancing social and economic security. This paper aims to conceptualize the influence of social reporting and sustainable development on Nigeria’s socioeconomic security. It is vital for its recommendations to the government and stakeholders on the way forward on sustainable development and national security.

A dissection through content analyses using the frustration-aggression and social contract theories was made on the influence of voluntary social reporting and sustainable development on socioeconomic security in Nigeria. An examination and assessment of the implementation of social disclosure by organizations and its effectiveness in promoting sustainable development with insights into the challenges and opportunities in a developing economy like the Nigerian context was done.

The results showed an increasingly negative trend in social and economic circles brought about by business organizations’ nonmandatory disclosure of social and environmental information. Therefore, it is suggested that governments should have a strong will to implement mandatory reporting to avoid future political catastrophes.

Implications emerged from this study inform policymakers, businesses and other stakeholders on the ways to enhance mandatory social sustainability in Nigeria.

This report is unique in the sense that it considers the interplay between sustainable development and socioeconomic security moderated by voluntary social disclosure as a virgin area in studies that involve developing economies.

Electrical characteristics of transformer oil (TO) have been studied during normal and thermal aging conditions. In this paper, breakdown voltage (BDV), partial discharge (PD), heat transfer results and the physical mechanisms considering the impact of varying the diameter of Al₂O₃ nanoparticles (NPs) have been investigated. Different quantities of the two sizes of Al₂O₃ were added to the oil using a two-step method to determine the positive effect of NPs on the electrical and thermal properties of TO. Finally, the physical mechanisms related to the obtained experimental results have been performed.

The implementation of nanoparticles in this paper was provided by US Research Nanomaterials, Inc., USA. The provided Al₂O₃ NPs have an average particle size of 20–80 nm and a specific surface area of 138 and 58 m²/g, respectively, which have a purity of over 99%. Thermal aging has been done. The IEC 60156 standard has been implemented to calculate the BDV, and a 500-mL volume test cell (Apar TO 1020) has been used. PD test is performed according to Standard IEC 60343, and a JDEVS-PDMA 300 device was used for this test.

BDV tests indicate that 20 nm Al₂O₃ is more effective at improving BDV than 80 nm Al₂O₃, with an improvement of 113% compared to 99% for the latter. The analysis of Weibull probability at BDV indicates that 20 nm Al₂O₃ performs better, with improvements of 141%, 125% and 112% at probabilities of 1, 10 and 50%, respectively. The results of the PD tests using the PDPR pattern also show that 20 nm Al₂O₃ is superior. For the heat transfer test, 0.05 g/L of both diameters were used to ensure fair conditions, and again, the advantage was with 20 nm Al₂O₃ (23% vs 18%).

The effect of Al₂O₃ NP diameter (20 and 80 nm) on various properties of virgin and aged TO has been investigated experimentally in this paper to examine the effect of proposed NP on electrical improvement of TO.

Drawing on panarchy theory and adaptive cycles, this study aims to investigate the role of reorganisation capabilities on firms’ supply chain resilience. The conceptual model underpinned by panarchy theory is tested in the agrifood supply chains disrupted by a geopolitical crisis and faced with material shortage. The study considers circularity as a core reorganisational capability and measures its interplay with two other capabilities: new product development and resource reconfiguration capabilities to achieve supply chain resilience.

A quantitative research design is followed to test the relationships between circularity capabilities, resource reconfiguration capabilities, new product development capabilities and supply chain resilience. A cross-sectional survey is applied to a sample drawn from food manufacturers who are dependent on wheat and sunflower oil as raw material and who are faced with material shortages in the aftermath of a geopolitical crisis. Measurement models and hypotheses are tested with the partial least squared structural equation modelling (PLS-SEM) based on 324 responses.

The results show that new product development and resource reconfiguration capabilities fully mediate the relationship between circularity capabilities and supply chain resilience. In other words, the food producers achieved supply chain resilience in response to agrifood supply chain disruption when they mobilised circularity capabilities in combination with new product development and resource reconfiguration capabilities.

The findings suggest that producers in the agrifood industry and even those in other industries need to develop circularity capabilities in combination with new product development and resource reconfiguration capabilities to tackle supply chain disruptions. In a world that is challenged by geopolitical and climate-related crises, this means leveraging 3R practices as well as resource substitution and reconfiguration in new product development processes.

The study explores the release and reorganisation phases of adaptive cycles in a panarchy by analysing the interplay between different capabilities for building supply chain resilience in response to disruptions challenging supply chains from higher levels of the panarchy. The results extend the theoretical debate between circularity and supply chain resilience to an empirical setting and suggest the introduction of new variables to this relationship.

The purpose of this study is to present a mini-integrated review on upcycling as a marketing strategy used by brands in promoting sustainability. Upcycling has emerged as a promising strategy for sustainability in the fashion industry. Activities within the industry have resulted in the release of toxic chemicals, carbon emissions and unsustainable products with significant environmental impacts. This has influenced manufacturers and researchers to adopt alternative but sustainable approaches.

In this mini-integrated review, relevant documents and information were sourced from appropriate databases and websites to provide a brief insight into upcycling as a marketing tool.

This mini-integrated review further provides insight into how effective upcycling can be integrated into a brand’s marketing strategy as a tool to communicate its commitment to sustainability and the production of high-value products for consumer satisfaction. It concludes that the fashion industry has a significant impact on the environment, and the practice of upcycling has surfaced as a potential solution to address issues of sustainability paving the way for further studies.

Brands use upcycling to differentiate themselves from competitors and appeal to consumers who prioritize sustainability. By emphasizing the environmental benefits of upcycling, brands can position themselves as leaders in the domain of sustainable fashion practices.

How does chronic illness shape the daily lives of those it affects? What about the families of those affected by chronic illness? For those who have one or more chronic illnesses, the daily impact of their illness is a topic that is not often talked about with their physicians, let alone close friends or family members. In this piece, the author utilizes a layered methodological approach coined, “emotional introspection” (Jago, 2002, p. 730), to illuminate her own experience with chronic illness as a young person with a family, whose daily experiences with chronic illness often go misunderstood by others. Using a social constructionist lens which focuses on stigma, the author also reflects on the consequences of understanding the daily impacts of chronic illness through a rigid, stagnant lens. Finally, the author draws on the analysis of her and her own family’s experiences with chronic illness to demonstrate the need for research that brings to light the intricacies that shape not only the daily lives of those who have chronic illnesses but also their families.

The purpose of this study is to explore the process of scaling second-hand fashion and how different strategic paths develop over time. This is theoretically grounded in two distinct scaling logics synthesised from the literature: a process that includes strategies for organisational growth (breadth-scaling) and a process that influences change in formal and informal institutions (depth-scaling).

The paper presents a process-based study based on the growth of a second-hand fashion retail organisation over 20 years. Qualitative materials such as interviews, observations and documents were collected and analysed.

The findings illustrate how a circular business model (CBM) can make use of a mix of strategies aiming for both organisational growth and impacting practices and habits within the fashion industry. Strategies building on breadth-scaling logic are found to be a prerequisite for engaging with depth-scaling strategies since they contribute to necessary resources and confidence, while depth-scaling secures future scaling opportunities by changing the conditions for scale.

The study contributes to the relatively scant literature on the process of scaling CBMs by exploring how different strategic paths unfold over time. The process-based approach, in combination with the two scaling logics, gives new insights into how CBMs go from niche to mainstream and thus influence the transition to a circular economy (CE).

A key characteristic of powder bed fusion for polymers is that also the non-processed powder in the powder bed is exposed to elevated temperatures. This alters the properties of the remaining powder, which is compensated by refreshing the used powder with new powder. Nonetheless, it is discarded after a certain number of process iterations, which is economically and ecologically highly disadvantageous. Research works intensively to analyse and reduce the concurring effects responsible for powder ageing. This study aims to give a comprehensive overview of the cumulative changes in the powder and the printed parts when conducting several subsequent build cycles.

New polyamide powder (PA12) was used in a total of nine subsequent build cycles with constant sintering parameters and without powder refreshing. After each iteration, the powder and parts were tested for their morphological, thermal and rheological properties.

The results are related to three main changes in the powder during the build cycles: decreasing bulk density (through agglomeration), increasing melt viscosity (through polyamide post-condensation) and increasing melting peak and onset temperatures (through thermal annealing of the powder).

Even though the ageing of PA12 powder in powder bed fusion is well-known, it is not yet fully understood. Studies are not complete and due to different ageing conditions only partially comparable. The detailed study aims to help understand the related effects of powder ageing for process-relevant properties and to show which factors require control to limit the powder ageing.

The European Marriage Pattern (EMP) was characteristic of preindustrial northwestern Europe and, in recent years, has been proposed as an important factor in the rise of the West. Yet, the origins and ultimate causes of the EMP remain obscure. We examine a novel hypothesis that the EMP can emerge in geographic environments with a lighter infectious disease burden. We overcome significant challenges facing empirical analysis of premodern societies. Using a large, individual-level database of marriages from the county of Kent, England, as well as a spatial regression discontinuity approach, we demonstrate a robust association between physical ecology and female age at first marriage (FAFM). We also find that the two potential channels proposed in the literature play starkly different roles in explaining our finding. Specifically, we fail to find that pastoralism plays any significant role in explaining the EMP, while the mortality rate channel accounts for a significant portion of the observed relationship between the disease environment and FAFM.