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To improve the voltage quality in AC adjustable high-power-speed-drive applications, the purpose of the paper is to provide a large number of output levels without increasing the number of commutation cells in the three-phase, n-cells flying capacitor voltage source asymmetric Multilevel Inverter (MI). The concept is based on the selection of different ratios between the breakdown voltages of two successive power devices. The new mathematical model is developed under various ratios, allows a thorough investigation of the harmonic distortions, flying capacitor energy storage, flying capacitor voltage balancing controllability and blocking voltage insulated gate bipolar transistor (IGBT) capability.

The asymmetrical design provides a large number of output levels without increasing the number of commutation cells. The important new analytical expression of capacitors voltage distribution is derived and extended to any ratio between the switch breakdown voltages of two successive power devices.

The detailed simulation study of the proposed concept has been carried out using MATLAB/Simulink. The power switches control of the three-phase three-cell MI is assured by new phase-shifted-multi-carrier pulse width modulation. The space vector representation is used to show the regular and irregular step output voltage in the complex plan (α,β).

In the paper, the n cells flying capacitor inverter, which typically operates in the (n + 1) levels mode, was extended to (n + 2), (n + 3) … until 2ⁿ levels with regular or irregular step output voltage. Consequently, the claimed advantages of the asymmetric MI are to improve power quality by reducing harmonic distortions and to reduce the requirement on capacitive energy storage in the circuit.

The purpose of this paper is to study the mechanical behavior in fatigue tensile mode of different cross-ply laminates constituted of unidirectional carbon fibers, hybrid fibers and glass fibers in an epoxy matrix; and to identify and characterize the local damage in the laminated materials with the use of the acoustic emission (AE) technique.

The tests in the fatigue mode permitted the determination of the effect of the stacking sequences, thickness of 90° oriented layers and reinforcement types on the fatigue mechanical behavior of the laminated materials. The damage investigation in those materials is reached with the analysis of AE signals collected from fatigue tensile tests.

The results show the effects of reinforcement type, stacking sequences and thicknesses ratio of 90° and 0° layers on the mechanical behavior. A cluster analysis of AE data is achieved and the resulting clusters are correlated with the damage mechanism of specimens under loading tests.

The analysis of AE signals collected from tensile tests of the fatigue failure load allows the damage investigation in different types of cross-ply laminates which are differentiated by the reinforcement type, stacking sequences and thicknesses ratio of 90° and 0° layers.

The purpose of this paper is to explore the motivations and inhibitions linked to the entrepreneurial act in Tunisia, a country belonging to the Middle East and North Africa (MENA) region. The findings of such a study help to better understand why new graduates are reluctant to create their own firms in spite of the political efforts made by the government.

A qualitative approach is adopted. It is based on 38 semi-directive in-depth interviews conducted with new graduates in entrepreneurship, some of them being young entrepreneurs, and others who did not go through the entrepreneurial process. On the basis of the data collected, a thematic content analysis has been carried out.

A set of contextual and cultural factors has been highlighted by the analysis. When the context is characterised by poverty, mafia, corruption, or even by a popular revolution or a war in a neighbouring country, these factors may significantly affect new graduates’ decision to create their own firm. Besides, the entrepreneurial decision may be affected by cultural factors: the bureaucratic system, autocracy, and the existence of entrepreneurial milieus such as social class, region, and geographical regions.

The inductive qualitative approach adopted in a research study affects the generalisable character of the results. This study is also geographically limited to the great Tunis area (the capital and its suburbs).

This study has been carried out in a context of an emergent country from the MENA region. This special setting leads to the valorisation of an understudied set of contextual and cultural motivations and inhibitors of entrepreneurship.

The aim of the present study is to investigate the mechanical behaviour of cross‐ply laminates under static tensile and buckling loading. Different cross‐ply laminates constituting of carbon fibers (CFRP), hybrid fibers (HFRP) and glass fibers (GFRP) in an epoxy matrix were considered. This work is also interested in identifying and characterizing the local damage in the composites with the use of acoustic emission method (AE).

The cross‐ply laminates are differentiated by the stacking sequences, thickness of 90° oriented layers and reinforcement. They are subjected to the static tensile and buckling load. The damage investigation is reached by the analysis of acoustic emission signals collected from static buckling tests.

The results show the effects of reinforcement type, stacking sequences and thicknesses ratio of 90° and 0° layers on the stiffness, failure load and displacement. A cluster analysis of acoustic emission data is achieved and the results are correlated to the damage mechanism of specimens under buckling tests.

The analysis of acoustic emission signals collected from static buckling tests under loading levels of 40, 60 and 100 per cent of the static failure load allows the damage investigation in cross‐ply laminates.

This paper treats the problem of scheduling seafaring staff inspired from a real case study, where the shipowner operates several vessel categories that require specific skills aiming to achieve a fair workload distribution and minimizing incompatibility between workers while meeting legal constraints, including requirements for days off and rest intervals between shifts.

A mixed integer linear problem (MILP) formulation has been built to address the seafaring staff scheduling problem by integrating multiple objectives and constraints. The model’s performance is tested through experimental results across varying parameter adjustments.

Our model was tested and validated using the XPRESS solver, and the results demonstrate its effectiveness in meeting the specified objectives and constraints. Notably, findings reveal that increasing the number of qualified workers leads to improved gains, until a certain threshold. Additionally, expanding the size of the workforce can result in longer execution times, specifically when incompatibility increases.

The originality of this study lies in proposing a generic novel model that deals with maritime staff scheduling, incorporating worker incompatibilities and workload fairness as key objectives.

Continuum robots modeling, be it from a hard or soft class, is giving rise to several challenges compared with rigid robots. These challenges are mainly due to kinematic redundancy, dynamic nonlinearity and high flexibility. This paper aims initially at designing a hard class of continuum robots, namely, cable-driven continuum robot (CDCR) and equally at developing their kinematic and dynamic models.

First, the CDCR prototype is constructed, and its description is made. Second, kinematic models are established based on the constant curvature assumption and inextensible bending section. Third, by using the Lagrange method, the dynamic model is derived under some simplifications and based on the kinematic equations, in which the flexible backbone’s elasticity modulus was identified experimentally. Finally, the static model of the CDCR is also derived based on the dynamic model.

Numerical examples are carried out using Matlab software to verify the static and dynamic models. Moreover, the static model is validated by comparing the simulation’s results to the real measurements that have been provided with satisfactory results.

To reduce the complexity of the dynamic model’s expressions and avoid the numerical singularity when the bending angle is close to zero, some simplifications have been taken, especially for the kinetic energy terms, by using the nonlinear functions approximation. Hence, the main advantage of this analytical-approximate solution is that it can be applied in the bending angle that ranges up to 2p with reasonable errors, unlike the previously proposed techniques. Furthermore, the resulting dynamic model has, to some extent, the proprieties of simplicity, accuracy and fast computation time. Ultimately, the obtained results from the simulations and real measurements demonstrate that the considered CDCR’s static and dynamic models are feasible.

The purpose of this study is to investigate factors influencing the net stable funding ratio (NSFR) in the Islamic banking system. More specifically, the authors analyze the impact of the deposit structure on the liquidity ratio using the two-step generalized method of moments approach during the 2000–2014 period.

Based on IFSB-12 and the GN-6, the authors calculated the NSFR for 35 Islamic banks operating in the Middle East and North Africa (MENA) region.

The findings of this study show the following: first, ratio of profit-sharing investment accounts have a positive impact on the NSFR, while ratio of non profit-sharing investment accounts increase the maturity transformation risk; second, the results highlight that asset risk, bank capital and the business cycle have a positive impact on the liquidity ratio, while the returns on assets, bank size and market concentration have a negative impact; and third, these results support the IFSB’s efforts in developing guidelines for modifying the NSFR to enhance the liquidity risk management of institutions offering Islamic financial services.

The most prominent limitation of this research is the availability of data.

These results will be useful for authorities and policy makers seeking to clarify the implications of adopting the liquidity requirement for banking behavior.

This study contributes to the knowledge in this area by improving our understanding of liquidity risk management during liquidity stress periods. It analyzes the modified NSFR that was adopted by the IFSB. Besides, this study fills a gap in the literature. Previous studies have used the conventional ratios to determinate the main factors of the maturity transformation risk in a full-fledged Islamic bank based on an early version of NSFR. Finally, most studies focus on the NSFR as proposed by the Basel Committee, whereas the authors investigate the case of the dual-banking system in the emerging economies of seven Arab countries in the MENA region.

This study aims to examine the association between nurses’ ageism and their knowledge about aging and socio-demographic and professional characteristics in recent international nursing research studies.

An extensive search of seven databases covering papers since 2000 was undertaken and Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed.

Ageism among nurses is still poorly understood. It is evident that ageism is associated with poor nurses’ level of knowledge about aging. A range of nurses’ demographical and professional characteristics have been examined as potential predictors of ageism, but they were inconsistent with positive, negative and neutral associations.

There is a lack of robustly designed studies investigating the association of nurses’ level of knowledge about aging and their socio-demographical and professional characteristics to ageism. Future descriptive-correlational and interventional studies are recommended to understand and target ageism in health-care settings.

This literature scoping review aims to investigate if, how and why eating behaviours change after a crisis event such as a natural disaster, financial crisis or pandemic in high-income countries.

The COVID-19 pandemic and resulting “lockdowns” and social distancing measures have changed access to food, the types of food consumed and usual eating behaviours. Early research on the effect of the COVID-19 pandemic is compared with existing literature on other high-impact crises in high-income countries around the world, such as Hurricane Katrina and the Global Financial Crisis. A search of four electronic databases in August 2020 of literature from 2000 to 2020 yielded 50 relevant publications that were included in the qualitative thematic analysis.

The analysis found that crisis events made accessing food more difficult and led to increased food insecurity. Home cooking, sharing food and eating together (within households during the pandemic) all increased during and after a crisis. Resources often reduced and needed to be pooled. Crises had a multi-directional impact on dietary patterns, and the motivators for dietary pattern change differ between populations and crises.

In conclusion, eating behaviours impacted by crises because of the disruption of food systems, increased food insecurity and changes in daily routines. Community networks were a strong protective factor against adverse outcomes from food insecurity.

This study aims to investigate the relationship between related party transactions (RPTs), specifically sales and purchases, and financial distress. It also explores the moderating role of various corporate governance mechanisms and audit-firm characteristics in this relationship.

This study spans the period before and during the COVID-19 pandemic and uses a logistic regression model focusing on an eight-year noncylindrical panel data set, covering a sample of Omani listed companies from 2014 to 2021.

The empirical findings reveal a contrasting relationship between RPT sales and financial distress: a significant negative relationship in the postpandemic period, and a positive relationship in the prepandemic period. Conversely, RPT purchases exhibit a consistently significant positive relationship across all periods. The presence of a Big Four audit-firm and audit delay are notable moderating variables associated with audit-firm attributes. Additionally, the board’s review of RPT transactions, size, meetings and independence are significant moderator variables pertaining to corporate governance.

This study provides empirical evidence to inform regulators of the efficiency and opportunistic aspects of RPTs in relation to financial distress. The study’s findings offer valuable guidance to managers by suggesting ways to reinforce corporate governance practices and strengthen audit mechanisms to counteract the negative consequences of RPTs.

To the best of the author’s knowledge, this study is the first to explore the direct relationship between both RPT sales and purchases and financial distress while also examining the moderating effect of corporate governance and audit attributes. This comprehensive approach distinguishes itself from its unique contributions to the field.