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This paper aims to present a detailed investigation on the parameter estimation of a photovoltaic (PV) module by using a simplified two-diode model.

The studied PV module in this paper resembles an ideal two-diode model, and to reduce the computational time, the proposed model has a photocurrent source and two ideal-diodes and neglects the series and shunt resistances. Hence, for calculating the unknown parameters, only four parameters are required from the datasheet. Moreover, the studied model is simple and uses an easy modeling approach which is free from complexities.

The performance of the PV module is analyzed under non-standard test conditions by considering partial shading at different shaded levels, and it is found that the model has less computational time and gives accurate results.

The usefulness of this PV model is demonstrated with the help of several illustrative figures, and the performance of the PV module is evaluated.

This paper aims to elaborate on the optimization of two particular cryptocurrency portfolios in a mean-variance framework. In general, cryptocurrencies can be classified to as coins and tokens where the first can be thought of as a medium of exchange and the latter accounts for security or utility tokens depending upon its design.

Against this backdrop, this empirical study distinguishes, in particular, between pure coin and token portfolios. Both portfolios are optimized by maximizing the Sharpe ratio and, subsequently, compared with alternative portfolio strategies.

The empirical findings demonstrate that the maximum utility portfolio of coins, with a risk aversion of λ = 10, outweighs alternative frameworks. The portfolios optimized by maximizing the Sharpe ratio for both coins and tokens indicate a rather poor performance. Testing the maximized utility for different levels of risk aversion confirms the findings of this empirical study and confers them more robustness.

Further investigation is strongly recommended as tokens represent a new phenomenon in the cryptocurrency universe, for which only a limited amount of data are available, which restricts the sampling. Furthermore, future study is to include more sophisticated optimization models using different constraints in portfolio creation.

In light of the persistently substantial volatility in cryptocurrency markets, the empirical findings assert that portfolio managers are advised to construct a global minimum variance portfolio. In the absence of sophisticated optimization models, private investors can invest according to the market values of cryptocurrencies. Despite minor differences in the risk and reward ratios of the portfolios tested, tokens tend to be more speculative, especially, if the Tether token is excluded, which may require enhanced supervision and investor protection by regulating authorities.

As the current literature investigates on diversification effects of blended cryptocurrency portfolios rather than making an explicit distinction, this paper reflects one of the first to explore the investability and role of diversifying coins and tokens using a classic Markowitz approach.

The purpose of this study was to explore the views of autistic people, carers and practitioners regarding the barriers autistic employees face at work (Study 1) and to use these views to inform the design of an employment programme for autistic employees without learning disabilities (Study 2).

In Study 1, 16 (20%) carers, 17 (21%) practitioners and 47 (59%) autistic adults who had been or were currently employed, answered a survey regarding barriers at work. Study 2 evaluates the efficacy of a set of profiling assessment tools (PA) developed to help employers make individually-tailored adjustments for their autistic employees by delivering an employment programme consisting of 15, 8-week work placements.

In Study 1, only 25% of autistic adults reported having had adjustments in the workplace and all groups reported this as the main barrier – alongside employers’ lack of understanding. Two sets of results demonstrate the efficacy of the PA tools in addressing this barrier. First, a comparative cost simulation revealed a cost-saving in terms of on-job support of £6.67 per participant per hour worked relative to published data from another programme. Second, 83% of autistic employees reported having had the right adjustments at work.

This is an exploratory study that did not include a comparison group. Hence, it was not possible to evaluate the efficacy of the PA tools relative to a standard employment programme intervention, nor to assess cost reduction, which currently is only estimated from already available published data.

Overall the findings from these studies demonstrate that the time invested in the high-quality assessment of the profile of autistic employees results in saving costs over time and better outcomes.

The originality of the Autism Centre for Employment programme resides in that, unlike other programmes, it shifts the focus from helping autistic employees to helping their employers.

Contrary to want-based services, customer participation has got lesser attention in high-credence services like health care. Customer participation for patients with chronic illnesses could be life-threatening and goes beyond the service organization’s physical environment. Realizing the importance of transformative service research in health-care services, this study aims to propose and validate the conceptualization of customer participation for patients with chronic illnesses.

The study uses sequential exploratory research design with mixed method research. The first phase is a qualitative exploration of the nature and meaning of customer participation by synthesizing theory and insights from semi-structured interviews (N = 75) with doctors, patients and paramedical staff. Next, survey data (N = 690) of patients with chronic illnesses is used to validate the proposed conceptualization. Finally, nomological validity was also tested on an additional survey data set (N = 362) using SEM and FsQCA.

The findings reveal that health-care customer participation is a three-dimensional behavioral construct in which a customer can participate by sharing information, involving in decision-making and ensuring compliance. The study also demonstrates that customer participation is a critical driver of satisfaction with life and perceived control on illness.

The research provides policy guidelines for owners and operators of health-care organizations in developing frameworks for collecting participation data, which can be used in strategies for seeking customer participation.

The research conceptualizes and validates “customer participation” as a multidimensional higher-order construct for patients with chronic illnesses, rarely focused in services marketing and management research on health care.

This study aims to investigate the impact of the 2022 collapse of the Terra-Luna ecosystem on volatility correlations among digital assets, including U.S. Terra, Luna, Bitcoin, Ether, a Decentralized Finance index and U.S.-sourced conventional assets stocks, bonds, oil, gold and the dollar index. The primary research question addresses whether correlations increased between digital and conventional assets during the collapse.

A dynamic conditional correlation generalized autoregressive conditional heteroskedasticity model was used to examine changes in volatility correlations during the market crash. Specifically, a data set of 1,442 close prices from 30-minute interval candles of digital and conventional asset prices are considered to provide a granular view of market dynamics during the sample period from January 3rd, 2022, to May 31st, 2022, including the crash event.

While the dynamic conditional correlation plots of the model indicate increased volatility, the results do not offer sufficient evidence to confirm an increase in correlations between digital and conventional assets during the Terra-Luna downfall. Furthermore, the authors confirm Bitcoin’s role as a diversifier with oil and observe the dollar index maintaining a negative correlation with Bitcoin during the crash, supporting Bitcoin’s function as a hedge against the U.S. dollar. However, the findings during the crash diverge from previous studies, reflecting shifts in correlation patterns in broader market downturns. Specifically, the authors identify the need for adaptive capital allocation strategies, as gold’s oscillation during the period suggests it may not serve as an effective hedge during black swan events.

The findings provide insights for investors, financial institutions and regulators to improve risk management, portfolio diversification, trading strategies and the formulation of consumer protection regulations. In addition, the results underscore the challenges of mitigating risks beyond regulatory measures and emphasize the importance of exercising caution for investors.

This study addresses the research gap in changes between conventional and digital asset volatility correlations during collapses in the digital asset space.

The purpose of this research is to examine the impact of e‐service quality, customer perceived value, and customer satisfaction on customer loyalty in an online shopping environment.

There were two studies performed in this research. Study 1 validated the self‐regulating processes; Study 2 tested the moderating effects of customer perceived value between satisfaction and loyalty. Structural equation modelling techniques and linear hierarchical regression models were used to test the causal model.

The study demonstrated that e‐service quality and customer perceived value influence customer satisfaction, and then influence customer loyalty. In addition this study found that customers with a high perceived value have a stronger relationship between satisfaction and customer loyalty than customers with a low perceived value.

We found that there are emotional and rational routes influencing customer loyalty in the online shopping process. This will contribute to other research that clarifies the influencing process of online shoppers' motivation and behaviour.

In the pre‐purchase stage, online retailers should focus on attracting consumers by the quality of e‐service. In the purchase stage, online retailers should address the emotional factors, such as customer satisfaction. In the post‐purchase stage, rational factors – such as customer perceived value – play important roles because they can strengthen the relationship between satisfaction and loyalty.

This study viewed the purchase process as a different stage as consumers may make a choice at each of the purchase stages. Moreover this study found a way to examine the relationship between customer satisfaction and loyalty by exploring the moderating effects of customer perceived value.

Tea contains high content of phenolics which are well-known to act as antioxidants. As such, there are claims that the consumption of infusion of tea could help ameliorate free radical-induced diseases; this therapeutic activity would depend on the amount of phenolics that is soluble and the amount that is absorbed and available for metabolic activity when consumed. The purpose of this study is to analyze the content of phenolics and antioxidant activity of some health tea and also to study the effect of addition of sugar and milk on in-vitro availability of phenolics in tea, cocoa and coffee drinks.

Seven brands of health tea, two brands of cocoa drink, one brand each of coffee, powdered milk and sugar were selected. The tea samples were analyzed for pH, titratable acidity, total phenol and antioxidant activity using Folin–Ciocalteau and 202-diphenyl-1-picryl-hydrazil 28DPPH-29-20 reagents. In-vitro simulated digestion modeling stomach and small intestine were carried out on tea infusion, coffee and cocoa drinks with or without sugar, and phenolic availability was analyzed.

The result indicated that pH, titratable acidity and total phenolics ranged from 4.5 to 5.6, 0.167 to 0.837 (as maleic acid) and 1.15 to 1.17 mg/g gallic acid equivalent, respectively. Black tea recorded the highest phenolic content, in-vitro phenolic availability and antioxidant activity. Addition of sugar to black tea and chocolate drink caused a significant decrease in the in-vitro available phenolics, while the addition of milk leads to a significant enhancement.

The data obtained in this study can be used nutritionally and commercially to show the impact of adding sugar or milk on the content of phenolics and their bioavailability in-vitro. The study justifies the claim that tea could help ameliorate free radical-induced health defects.

Assessment of antioxidant activity of food should not be based only on the content of total phenolics but on the amount that is bioavailable in the body system when the food is consumed.

Consumption of tea, cocoa and coffee drinks with milk and sugar have been found to enhance or inhibit phenolics. Therefore, the optimum level of these additives should be determined if the drinks were meant for therapeutic purposes.

Results obtained may provide some useful information for considering the bioavailability of phenolics present in tea and beverages in view of consumption/digestion in our body as well as interference of sugar and milk as the additives.

This public-sourced case describes the latest restructuring efforts by Deutsche Bank (DB) and gives a short history of prior restructuring efforts from the decade before. In July 2019, Christian Sewing, the new CEO of DB, announced a series of measures that included, among others, the elimination of global equity trading, the layoff of 18,000 employees, the creation of a “bad bank” to transfer noncore assets, and the suspension of dividends until 2022. The case describes key decisions a bank CEO makes when a bank needs to change course to return to profitability and growth. The case offers an opportunity to debate these key decisions, as well as discuss some of the prior ones during earlier restructuring efforts, and put the students in the CEO's shoes: What would you do and why? The case also describes key banking performance metrics (e.g., ROE, ROA) and other critical variables such as those reflecting capital health (Tier 1 ratio), as well as gives an overview of the bank business model and factors impacting bank profitability and value.