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The lightning phenomenon is one of the main threats in photovoltaic (PV) applications. Suitable protection systems avoid major damages from direct strikes but also nearby strikes may induce overvoltage transients in the module itself and in the power conditioning circuitry, which can permanently damage the system. The effects on the PV system sensibly depend on the converter topology and on the adopted power switch. In the present study, a comparative analysis of the transient response due to a nearby lightning strike (LS) is carried out for three PV systems, each equipped with a different converter, namely, boost, buck and buck–boost, based on either silicon carbide metal oxide semiconductor field effect transistors (SiC MOSFET) or insulated gate bipolar transistors controlled power switch devices, allowing in this way an analysis at different switching frequencies. The purpose of this paper is to present the results of the numerical analysis to help the design of suited protection systems.

Using a recently introduced three-dimensional semi-analytical method to simulate the electromagnetic transients caused in PV modules by nearby LSs, we investigate numerically the effect of a LS on the electronic circuits connecting the module to the alternate current (AC) power systems. This study adopts numerical simulations because experimental analyses are not easy to perform and does not grant a sufficient coverage of all statistically relevant aspects. The approach was validated in a previous paper against available experimental data.

It is found that the load voltage is not severely interested by the strike effects, thanks to the low pass filters present at the converter output, whereas a relatively high overvoltage develops between the negative pin of the inner circuitry and the “ground” voltage reference. The overcurrent present in the active switches is hardly comparable because of the different topologies and working frequencies; however, the highest overcurrent is observed in the buck converter topology, with SiC MOSFET technology, although it shows the fastest decay.

This research proposes, to the best of the authors’ knowledge, a comprehensive comparison of the indirect lighting strike effects on the converter connected to PV panels. A proper design of the lightning and surge protection system should take into account such aspects to reduce the risk of induced overvoltage and overcurrent transients.

Despite increasing focus among scholars and practitioners on the design of product-service systems (PSS), there exists no compilation of current knowledge on the role played by small and medium-sized enterprises (SMEs) in designing such systems. Thus, this paper sets out to identify and organise the existing research and suggest questions for future research.

A systematic literature review was performed to identify and provide in-depth details on key themes in the literature addressing the design of PSS in SMEs.

This paper identifies five themes in the literature on the design of PSS in SMEs: motives, challenges, SME characteristics, methods and digitalisation. The themes are interrelated, and SME characteristics seem to be at the core as they are related to all the other themes. Gaps in the current knowledge are identified, and questions for future research are suggested.

The suggestions for future research provide a starting point for expanding the research on PSS design and devising practical support for SMEs.

The purpose of this paper is to examine the amount of online information reported by Spanish municipal-owned enterprises (MOEs) according to the legal requirements indicated in the Spanish Law 19/2013 on Transparency and Good Governance. In addition, the authors analyze how different variables can affect the extent of online information reported by such enterprises.

To do this, we conducted a content analysis of the web pages of Spanish MOEs located in cities with more than 100.000 habitants, as well as those cities that are provincial capitals. To find information about these enterprises, the authors accessed the General Intervention Board of the State Administration (IGAE) webpage (www.igae.pap.minhafp.gob.es/sitios/igae/es-ES/Paginas/inicio.aspx). This sample was composed of 273 enterprises majority owned and controlled by local governments.

The findings reveal that the amount of information reported by Spanish MOEs, in accordance with the legal requirements, is quite reduced. The most influential variables for explaining Spanish MOEs’ commitment to information disclosure are population size, political positioning of the local government and reputation.

This study seeks to contribute to the scarce literature on mandatory transparency in the public sector as well as to reinforce the degree of compliance with requirements of information disclosure.

The purpose of this study is to propose a novel relaxation modified factor to accelerate the numerical solution of the radiative transfer equation (RTE) with several high-resolution total variation diminishing schemes. The methodology proposed is denoted as the X-factor method.

The X-factor method was compared with the technique deferred-correction (DC) for the calculations of a two-dimensional cavity with absorting-emiting-scatteting gray media using the discrete ordinates method. Four parameters were considered to evaluate: the absorption coefficient, the emissivity of boundary surface, the scattering albedo and under-relaxation factor.

The results showed the central processing unit (CPU) time of X-factor method was lower than DC. The reductions of CPU time with the X-factor method were observed from 0.6 to 75.4%.

The superiority of the X-factor method over DC was showed with the reduction of CPU time of the numerical solution of RTE for evaluated cases.

To redesign the spare parts (MRO) inventory management at Company XYZ's warehouse, considering the conditions after the COVID-19 pandemic.

To address this research project, the authors integrated three methodologies: action research, Lean Six Sigma (DMAIC) and Cross Industry Standard Process for Data Mining. These methodologies integrated the Lean Six Sigma (LSS) 4.0 framework applied in this project.

The spare parts inventory value was reduced by 15%, and inventory turnover increased by 120% without negatively impacting the internal service level.

Practitioners leading or participating in continuous improvement projects (CIPs) should consider data quality (data available and data trustworthiness), problem-solving approach and target area involvement to achieve CIP goals. Otherwise, the LSS 4.0 could fail or extend its duration by several weeks or months.

This project shows the importance of controlling a target area before deciding to conduct a LSS 4.0 project. To address this problem, the LSS 4.0 team implemented 5S during the measure phase of the DMAIC. Also, this project offers significant practitioner and theoretical contributions to the body of knowledge about LSS 4.0.

This paper aims to present an evolutionary algorithm (EA) to accelerate the convergence for the radiative transfer equation (RTE) numerical solution using high-order and high-resolution schemes by the relaxation coefficients optimization.

The objective function minimizes the residual value difference between iterations in each control volume until its difference is lower than the convergence criterion. The EA approach is evaluated in two configurations, a two-dimensional cavity with scattering media and absorbing media.

Experimental results show the capacity to obtain the numerical solution for both cases on all interpolation schemes tested by the EA approach. The EA approach reduces CPU time for the RTE numerical solution using SUPERBEE, SWEBY and MUSCL schemes until 97% and 135% in scattering and absorbing media cases, respectively. The relaxation coefficients optimized every two numerical solution iterations achieve a significant reduction of the CPU time compared to the deferred correction procedure with fixed relaxation coefficients.

The proposed EA approach for the RTE numerical solution effectively reduces the CPU time compared to the DC procedure with fixed relaxation coefficients.

The purpose of this paper is to analyze the mediating role of board effectiveness (understood as the capacity to efficiently manage and control all functions to guarantee the company’s prosperity) in the relationship between board diversity and firm performance.

The authors use partial least squares methodology to test the direct and indirect relationships between gender diversity in boards of directors and business performance.

Although the relationship between the presence of women on the board and the board’s effectiveness is statistically significant, this relationship is negative. However, board effectiveness (measured by the three constructs: strategic control, organizational innovation and decision-making) has a positive and statistically significant effect on business performance. Finally, there is a positive, but not statistically significant, relationship between gender diversity and firm performance.

The study has a small sample size, and most of the boards of directors analyzed are unequal with only a few companies achieving gender parity.

Public institutions must promote actions to achieve a critical mass of women directors and managers, so that women transcend a merely “symbolic” role on a board and are able to develop their skills and characteristics, thereby improving a board’s effectiveness and business performance.

This paper makes a theoretical contribution to the diversity and governance literature by providing a better understanding of the relationship between board gender diversity and firm performance. It considers the influence of women on the board through a holistic framework, analyzing the mediating role of the board’s effectiveness.

Regardless of the noteworthy growth in research and practice associating corporate social responsibility (CSR) with human resource management, little has been written in regard to one major dimension of CSR in small- and medium-sized enterprises (SMEs), as CSR policies and practices are directed toward employees. The purpose of this paper is to develop and test a conceptual framework connecting socially responsible human resource management (SRHRM) to competitive performance that fits small business.

In order to get empirical evidence, structural equation modeling technique was applied on the data from 481 Spanish SMEs.

Results confirm both the direct contribution of SRHRM to business competitiveness and the multiple effects resulting from including two variables of additional interest for the relationship under study: employee’s commitment and relational marketing.

One of the main research limitations is that the paper only reflects the perceptions of owners/managers of SMEs. Although it was believed that the respondents give reliable and accurate information about the way their firms are involved in CSR practices, there is a possibility that they might provide incorrect or incomplete information.

The relationships proposed have never been studied before in context of SMEs. This is a worthwhile endeavor, which makes an empirical contribution.

An emerging market in human milk exists for both nutritional and biomedical research purposes. This commercialisation of human milk, however, raises issues about the exploitation and violence against women.

This paper explores the framing of the issues as one of human rights, and whether the shifting of gender issues away from gender-specific spaces in legal and ethical debates, makes their ethical consideration and the tangible consequences from these considerations, into a potential further sources of exploitation and other forms of violence against women.

The authors find the commoditisation of human milk as a nutritional product deprives women from the centrality of their roles and, therefore, from the upholding of women rights and the adequate prevention of violence against women. They identify an emerging space where trafficking in women and girls can occur for their milk as part of a broader set of practices of reproductive exploitation. They also identify that existing legal, ethical and research discussions often frame labour or organ trafficking as the appropriate framework but find this inadequate to address the inherently gendered aspect of reproductive exploitation. The current response makes trafficking in women for their milk a potential practice while concealing the structural inequalities that underpin women’s experiences as the buyers and sellers of human milk.

The regulation of human milk sale should therefore move from a public health paradigm focused on safety to one of health and women’s rights, whereas human trafficking laws around the world should explicitly address reproductive exploitation.

Emerging forms of exploitation, such as human milk sale remain underdiscussed alongside other more prominent forms of reproductive exploitation, such as surrogacy. The authors call for explicit consideration of the emerging trade as its burdens fall exclusively on women and existing frameworks for addressing exploitation often overlook these emerging practices and the structural inequalities faced by women that drive these trades.

The purpose of this paper is to evaluate a continuous improvement project (CIP) at a Mexican university designed to increase engineering graduate student loyalty.

A plan-do-check-act problem-solving methodology was implemented, and a SERVQUAL survey was conducted on 67 master’s engineering students.

Five factors were found to affect student loyalty: facility cleanliness; faculty teaching skills; evening student services; master’s degree student management roles at work; and master’s degree students’ ages. After the implementation of the improvement and control actions, there was a 7.7% increase in the engineering master’s degree students’ loyalty scores.

However, there were several research limitations: data availability (such as student loyalty, student satisfaction and a small master’s degree student population size) and factors outside the CIP’s scope (such as the country’s economic situation, university rankings, master’s programme accreditations and COVID-19).

The findings from this research study could be used by other higher education institutions (HEIs)to improve student loyalty and as a reference when conducting similar studies in other service organisations such as hospitals and hotels.

This research work took a different approach in assessing student satisfaction and student loyalty in a HEI by using the SERVQUAL survey as the data collection instrument for conducting CIP.