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The ionization of the air surrounding the phase conductor in high-voltage transmission lines results in a phenomenon known as the Corona effect. To avoid this, Corona rings are used to dampen the electric field imposed on the insulator. The purpose of this study is to present a fast and intelligent surrogate model for determination of the electric field imposed on the surface of a 120 kV composite insulator, in presence of the Corona ring.

Usually, the structural design parameters of the Corona ring are selected through an optimization procedure combined with some numerical simulations such as finite element method (FEM). These methods are slow and computationally expensive and thus, extremely reducing the speed of optimization problems. In this paper, a novel surrogate model was proposed that could calculate the maximum electric field imposed on a ceramic insulator in a 120 kV line. The surrogate model was created based on the different scenarios of height, radius and inner radius of the Corona ring, as the inputs of the model, while the maximum electric field on the body of the insulator was considered as the output.

The proposed model was based on artificial intelligence techniques that have high accuracy and low computational time. Three methods were used here to develop the AI-based surrogate model, namely, Cascade forward neural network (CFNN), support vector regression and K-nearest neighbors regression. The results indicated that the CFNN has the highest accuracy among these methods with 99.81% R-squared and only 0.045468 root mean squared error while the testing time is less than 10 ms.

To the best of the authors’ knowledge, for the first time, a surrogate method is proposed for the prediction of the maximum electric field imposed on the high voltage insulators in the presence Corona ring which is faster than any conventional finite element method.

Life, in many ways, is simply grief waiting to happen. It is the emotions of death – simultaneously something ordinary and universal as well as extraordinary and unique – that we try to capture and make sense of with the notion of ‘grief’. The so-called ‘corona pandemic’ that has spread throughout the world during the past 2–3 years is in many ways a crisis of global proportions that, at its very core, is caused by and concerned with the fear of death and dying from a deadly disease. So far, six million people have died in the corona pandemic. The ways we grieve and mourn our dead are indicative and informative of the society/culture in which we live and the values, norms and ideas that prevail within it. This chapter deals with the emotion and practice of grief as it is particularly related to experiences of death and dying in a contemporary Western corona-ridden society. I explore challenges relating to the display of emotions, ritual practice and ceremonial closure – as well as the paradoxical way in which the corona pandemic has inaugurated a new great disappearing act of death and grief at a time when death and grief have been paramount experiences for many affected people. Today, we know more about grief than at any other time in human history, but the question remains whether we have become any better at accepting it, dealing with it and living with it.

This study aims to explore and verify the influence of the corona pandemic on the stock returns of the Palestinian companies listed on the Palestine Exchange during the period 2020–2021.

The research makes use of secondary financial data from 52 companies in the industrial, investment, services, banking and insurance sectors. Many financial ratios are calculated to assess stock returns: current ratio, cash ratio and average collection time as liquidity measures; debt-to-equity ratio as an indication of leverage or solvency; and net profit margin as an indicator of profitability. The research examines ratios between the (2020 and 2021) precorona outbreak using the Wilcoxon signed rank test and financial ratio analysis during the corona pandemic.

The findings show that liquidity in the investment, banking, insurance and industrial sectors has decreased significantly, whereas liquidity in the service sector has improved. The statistics reveal a considerable growth in debt in the service sector, while it stays unchanged in the other sectors. However, there is no discernible change in profitability during and after the corona outbreak.

The present research faced many limitations, such as the approach to gathering primary data, which depended heavily on disclosures, financial reports and secondary data, as well as only analyzing one context and one country.

The findings of this study can guide the Palestinian government and decision-makers to respond to the COVID-19 outbreak and must act quickly because strong short-term policies are more functional than long-term policy measures. In addition, the temporal discrepancy between their policy actions and financial regulations regarding the stage of the outbreak, integrating monetary treatment methods, strengthening their control over exchange rate fluctuations and extending the duration of financial participation measures that ensure stable exchange rates, such as attempting to restrict trade of the monetary system between countries was assessed to reduce the important monetary stimulation policy.

This study presents important facts and results for regulators and decision-makers regarding the investment, industry, banking, insurance and services sectors as sectors that are most affected by the corona pandemic as a sample for this study from the Palestinian companies listed in Palestine Stock Exchange due to the corona pandemic.

The purpose of this paper is to propose an optimum design of a corona ring for insulator strings using optimisation techniques, which are gravitational search algorithm (GSA) and imperialist competitive algorithm (ICA).

An insulator string model geometry with a corona ring was modelled in a finite element analysis software, and it was used to obtain the electric field distribution in the model. The design was optimised using GSA and ICA. The variables were the corona ring diameter, ring tube diameter and vertical position of the ring along the insulator string.

Using optimisation method, the minimum electric field magnitude on the insulator string with a corona ring design is lower than without using optimisation method. GSA yields better results than ICA in terms of the optimised corona ring design.

The proposed methods can help in improvement of corona ring design in reducing the electric field magnitude on the energised end of insulator strings.

A new method to design an optimum corona ring for insulator strings, which is using optimisation methods, has been developed in this work.

A technique for studying the propagation of surges on lines in the presence of corona and a lossy earth is presented. Each line section is modelled by lumped circuit components representing corona and earth effects. The component values are readily obtained from theoretical and experimental investigations. The circuit is solved in the time domain using transmission line modelling (TLM). The results show good agreement with other experimental and theoretical investigations.

A method is developed for calculating the power loss due to corona on three‐phase transmission lines in fair weather. In this method, emission of ions takes place from the coronating phase conductors into the surrounding space when the conductor surface field exceeds the corona onset value. The space charges are simulated by discrete line charges, and the charge simulation technique is used to calculate the charge emission from the phase conductors during corona periods over both the positive and negative half‐cycles. The displacement of the space charges is governed by the prevailing field, which sums the contributions of all discrete line charges in space and those simulating the phase conductor. The calculated corona power loss values agreed well with those measured experimentally.

This study aims to investigate how brand love and brand loyalty for three brands evolved during critical moments of the 2020 pandemic, and how they performed in the long run up to 2022.

An online longitudinal study, including a survey and Twitter data for three brands: Corona Extra, with a direct semantic association with the word coronavirus; Virus Vodka, with an indirect association; Modelo Especial, with no association with the virus name but from the same company as Corona Extra.

Despite external data indicating a harmful association between Corona Extra and coronavirus, this study's findings revealed that the brand maintained its brand love in the long run and increased brand loyalty during the critical moments of the pandemic. This study's data suggest that brand love and brand loyalty may be the underlying reasons for the increase in Corona Extra's brand equity during the pandemic.

The COVID-19 pandemic created a highly stressful situation for consumers and brands. Some brands' names had unfortunate semantic similarities with the virus terminology, which became an additional stressor during that time. This study harnessed the opportunity to investigate brand love and brand loyalty during the pandemic at four points in 2020 and one in 2022. The authors also examined relevant Twitter data during 2020.

The utterly un-nostalgic person is probably a non-existent being. At both a personal and collective level, we explore how nostalgia is experienced and in demand during times of transition, disjuncture, conflict and uncertainty. This chapter explores the emotion of nostalgia and connects it specifically to the current corona pandemic – the challenges of lockdowns and social distancing measures on interaction, feelings of loneliness and a generalised sense of uncertainty and despair, and also a rise of nostalgia as a possible response to these challenges. The predominant view of nostalgia put forth in this chapter is that nostalgia has the capacity to provide a great deal of benefit (meaning, hope, direction and purpose) to individuals, groups, institutions and societies at large. Indeed, nostalgia can be a tranquil feeling in a fearful world. We relate nostalgia to studies and experiences from the pandemic period and speculate on how the so-called ‘corona crisis’ may impact feelings of nostalgia in the post-pandemic world – perhaps even a nostalgia and longing for the pandemic period itself.

If the corona pandemic has in fact sparked a new (or renewed) interest in nostalgia in contemporary society due to the corona pandemic, it may indeed prove to be a positive thing, particularly if it makes it easier for people to deal with current feelings of adversity and anxiety. We suggest the nostalgia mood that is generated and perpetuated by the continuing twists and turns of the corona pandemic may – in the short and long run – prove useful in coping with and giving meaning to the problems and perplexing circumstances of life, rather than being a regressive phenomenon. Perhaps, something good may, in the end, grow from something bad?

In this paper, the electrical parameters of the duct electrostatic precipitators with bundle wires, as discharge electrodes, are calculated and reported. Variation of mobility for both ions and particles in the space surrounding the energized subwires is taken into consideration. The method used is based on numerically solving the main set of equations, defining the ionized field surrounding the subwires of the bundle wire‐duct electrostatic precipitators (BWDEP) with the presence of dust particles. This method predicts the electrical performance in the BWDEP irrespective of the number of subwires per bundle. The corona onset voltage around the periphery of each subwire of the bundled discharge electrodes of the duct electrostatic precipitators is determined. It changes from point to point at the subwire surface. The effects of different numbers of subwires per bundled electrode, as well as the subwires arrangement, on the electrical performance of the BWDEP are also reported and discussed in this paper. The present findings are correlated to the physics of the electrical corona discharge.

A financial statement analysis case uses the government-wide financial statements of Corona, CA to teach students about the financial overview provided in the new governmental financial reporting model. Educators are struggling to incorporate the new model in their governmental accounting curricula. The case analysis is beneficial to students in three ways. First, the active, case learning approach of using a real world example complements existing pedagogical materials for better mastery of the new reporting model. Second, the case approach of using ambiguity and alternative solutions promotes the development of analytical skills. Third, the written requirement and class discussion promotes the development of communication skills.