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The present study aims to encompass the bidirectional magnetized flowing of a hybrid-nanofluid over an unsteady stretching device with the inclusion of thermal radiation and entropy generation. Brick-shaped nanoparticles (zinc-oxide and ceria) are suspended in water, serving as the base-fluid to observe the performance of the hybrid mixture. The Maxwell thermal conductivity relation is employed to link the thermophysical attributes of the hybrid mixture with the host liquid. Additionally, a heat source/sink term is incorporated in the energy balance to enhance the impact of the investigation. Both prescribed-surface-temperature (PST) and prescribed-heat-flux (PHF) conditions are applied to inspect the thermal performance of the hybrid nanofluid.

The transport equations in Cartesian configuration are transformed into ordinary differential equations (ODEs), and an efficient method, namely the Keller-Box method (KBM), is utilized to solve the transformed system. Postprocessing is conducted to visually represent the velocity profile, thermal distribution, skin-friction coefficients, Bejan number, Nusselt number and entropy generation function against the variations of the involved parameters.

It is observed that more entropy is generated due to the increases in temperature difference and radiation parameters. The Bejan number initially declines but then improves with higher estimations of unsteadiness and Hartmann number. Overall, the thermal performance of the system is developed for the PST scenario than the PHF scenario for different estimations of the involved constraints.

To the best of the authors' knowledge, no investigation has been reported yet that explains the bidirectional flow of a CeO2-ZnO/water hybrid nanofluid with the combined effects of prescribed thermal aspects (PST and PHF) and entropy generation.

The current analysis produces the fractional sample of non-Newtonian Casson and Williamson boundary layer flow considering the heat flux and the slip velocity. An extended sheet with a nonuniform thickness causes the steady boundary layer flow’s temperature and velocity fields. Our purpose in this research is to use Akbari Ganji method (AGM) to solve equations and compare the accuracy of this method with the spectral collocation method.

The trial polynomials that will be utilized to carry out the AGM are then used to solve the nonlinear governing system of the PDEs, which has been transformed into a nonlinear collection of linked ODEs.

The profile of temperature and dimensionless velocity for different parameters were displayed graphically. Also, the effect of two different parameters simultaneously on the temperature is displayed in three dimensions. The results demonstrate that the skin-friction coefficient rises with growing magnetic numbers, whereas the Casson and the local Williamson parameters show reverse manners.

Moreover, the usefulness and precision of the presented approach are pleasing, as can be seen by comparing the results with previous research. Also, the calculated solutions utilizing the provided procedure were physically sufficient and precise.

In this paper, the authors study the nonlinear matrix equation Xp=Q±A(X-1+B)-1AT, that occurs in many applications such as in filtering, network systems, optimal control and control theory.

The authors present some theoretical results for the existence of the solution of this nonlinear matrix equation. Then the authors propose two iterative schemes without inversion to find the solution to the nonlinear matrix equation based on Newton's method and fixed-point iteration. Also the authors show that the proposed iterative schemes converge to the solution of the nonlinear matrix equation, under situations.

The efficiency indices of the proposed schemes are presented, and since the initial guesses of the proposed iterative schemes have a high cost, the authors reduce their cost by changing them. Therefore, compared to the previous scheme, the proposed schemes have superior efficiency indices.

Finally, the accuracy and effectiveness of the proposed schemes in comparison to an existing scheme are demonstrated by various numerical examples. Moreover, as an application, by using the proposed schemes, the authors can get the optimal controller state feedback of $x(t+1) = A x(t) + C v(t)$.

Within the two-tier bargaining system, the role of complementary collective bargaining is somewhat controversial. In this paper, the authors analyse collective agreements from a triple perspective: scanning the contents of firm-level complementary collective agreements (CCAs); identifying the factors that determine the probability of signing a CCA and analysing the relationship between the latter and firm performance with a focus on the role of different negotiated topics.

The empirical procedure is based on 2 main linked sources: longitudinal balance sheet data and a cross-sectional dataset of a representative sample of Italian firms with at least 15 employees, including some retrospective information. The innovative dataset derives from integrating multiple sources. The main empirical approaches include Generalized Method of Moments (GMM) estimations, multivariate regressions, as well as instrumental variable (IV) estimations to overcome simultaneity issues.

With respect to the probability of signing a CCA, on the firms' side, the authors find a positive role of the degree of firm capitalisation and affiliation with an employers' association and a negative role of family firms compared to non-family firms; on the workers' side, a positive role of the workers' unionisation rate and a positive but differentiated weight of workers' union representations and industrial conflicts. With regard to firm performance, the authors' estimates suggest that signing a CCA is associated with an average increase of 3% in total factor productivity (TFP) and 7.8% in labour productivity. By investigating the contents of the complementarity agreements, the authors show that bargaining a wider range of topics implies advantages that are not homogenous, benefitting more efficient firms. Moreover, the authors find a specific positive and significant role for three main interacting issues: economic incentives, organisation and employment.

The cross-sectional structure of the data on bargaining practices prevents detecting causal relationships due to either potential common driver(s) of both the target variables (firm performance) and bargaining practices (simultaneity bias) and unobservable time-invariant firm-level characteristics (heterogeneity bias).

According to the authors' results, policymakers should operate along four fiscal channels to spur the efficiency of firms, via CCA. First, tax incentives stimulate higher firm capitalisation, as this seems to be a CCA-favouring factor. Second, deduction in taxable income for union members, which should led to higher membership rates, hence raising the likelihood of obtaining a CCA. Third, incentives aimed at directly promoting the greater diffusion of CCAs as a source of improved performance. Fourth, fiscal tools aimed at favouring the negotiation of either specific contents or “bundles” of contents, which the authors' estimates show as an additional performance-enhancing tool of CCA practices.

The conceptualisation of the contents of CCA as organisational investments and the whole probability function of signing a CCA are quite innovative. Moreover, the econometric strategy takes account of several potential sources of bias when estimating the relevant coefficients at each stage, which is currently not fully considered in the literature. Finally, this is the first study to shed light on both the diverse outcomes associated with different negotiated topics (in terms of quantity and quality) and the distinction between short and medium-long term effects.

The purpose of this study is to investigate the relationship between fiscal policy (tax revenues and government expenditure) and economic happiness. The panel data are used from 2012 to 2016 for 18 countries of the Middle East and North Africa (MENA) region.

The study adopted the Barro (1990) model of endogeneity growth to characterize the relationship between fiscal policy and economic happiness. The study estimated the model by using the pooled ordinary least squares method, the fixed effects method and the random-effects method. In addition, the study used the dynamic estimate of this relationship rather than the conventional static estimate through the generalized method of moments’ method. This leads to overcoming the endogeneity problem between the dependent variable and the independent variables.

The main findings indicated that there is a negative and statistically significant relationship between nondistortionary taxes and economic happiness. Also, there is no relationship between public expenditure and economic happiness, whether productive or nonproductive. The results confirmed a positive and significant relationship between other revenues and economic happiness. The current study recommended the diversification of other public revenue sources to increase its contribution to public expenditure financing and the restructuring of the tax system, particularly nondistortionary taxes. These taxes must be replaced by other revenues or by distortionary taxes to increase economic happiness.

The research represents a strong starting base that can help researchers to conduct more studies on economic happiness by using different measures and comparing their results to find out the determinants of happiness. The relationship between economic happiness and fiscal policy with its different aspects requires more studies, especially the relationship between taxes and economic happiness in our region. The study of the relationship between public expenditure and economic happiness according to economic activities can guide decision-makers to direct the expenditure toward economic activities that achieve the happiness of their citizens. Enriching this study requires the availability of fiscal data for the entire MENA region for longer periods, which allow us to divide the countries of the region into petroleum and nonpetroleum countries, but the scarcity of data is one of the limitations of the study.

The governments of MENA countries should diversify other public revenue sources to increase the financing public expenditure by the expense of tax revenues, especially nondistortionary taxes, which would increase the economic happiness of their citizens.

This study is one of the rare studies that investigate the relationship between fiscal policy and economic happiness at the global level. This study contributed to filling the gap of this issue in the MENA region and enriching global literature through the experience of the MENA region. Moreover, this study investigated all aspects of fiscal policy, in contrast to other studies that focused on one of its aspects. The weakness in these studies is because of the lack of correlation between the sources of revenues and the face of their spending.

A lack of sufficient gainful employment opportunities in developing countries means that those at the bottom of the income ladder resort to self-employment for survival. While self-employment equalises inequality by providing earning opportunities to such individuals due to the ease of entry, it also creates a competitive environment among the self-employed, consequently widening inequality. In light of this, the study aims to determine the optimal level at which self-employment narrows inequality.

Five-yearly average data from 72 developing countries covering 2000–2019 is used. Inequality measures include Gini, and self-employment includes total, male and female participation levels. The empirical analysis is based on the dynamic two-step system Generalized Method of Moments (GMM) estimation approach, two-stage instrumental variables (2 SLS IV) approach and Sasabuchi (1980) and Lind and Mehlum (2010) test. Several robustness checks are used to validate the findings.

Prima facie, the study's findings suggest that self-employment equalises inequality in developing countries. The income-equalising effect can be seen, however, when the total, male and female self-employment levels are below the optimal of 54.22% of total employment, 52.50% of male employment and 54.19% of female employment, respectively. Inequality widens when self-employment exceeds these optimal levels. Further, the income-narrowing effect of self-employment is larger than its income-widening effect. When self-employment is below its optimal level, it reduces inequality 80 times more effectively than when it widens above the optimal levels. The corresponding figures for male and female self-employment are 90 and 52, respectively. Second, the income-equalising effects of self-employment are gender-specific.

Developing countries striving to achieve SDG 10 should limit self-employment to the above-mentioned levels. To this end, an inclusive approach to reducing inequality requires these countries to use selective and targeted policy interventions to create gainful employment opportunities for those above the identified optimal levels and eventually assist them in utilising these opportunities.

To the best of the author’s knowledge, this is the first study to determine the optimal levels at which self-employment equalises income in developing countries. As such, it makes novel contributions to both labour and development economics.

This study serves two objectives; first, it examined the impact of ownership structure and board characteristics on firm value; second, the moderating effects of board gender diversity (women appearance on board) and board ethnic diversity (Chinese, Indian, and Foreign ethnicities) have been examined on the relationship between ownership structure, board characteristics, and firm value.

The dynamic model, system generalized method of moments (S-GMM hereafter), is employed to control potential dynamic endogeneity, reverse causality, simultaneity and unobserved heterogeneity persistent in corporate governance-performance relationships during 2006–2017 of 483 Malaysian listed companies.

Findings pertaining to objective one reveal that there is a weak linkage between ownership structure and firm value, whereas board characteristics significantly affect firm performance based on resource dependence theory. While considering the results of objective two, there is mixed evidence of moderating impact of board gender and ethnic diversity on ownership structure, board characteristics and performance nexus.

The findings of the study are practically significant for regulatory bodies, namely, Bursa Malaysia, Securities Commission (SC) Malaysia, and policymakers to develop guidelines for ownership structure variables. Moreover, Malaysian firms need to disperse their concentrated ownership structure for enhanced firm value. In addition, board characteristics significantly affect firm performance in Malaysian listed companies.

The paper contributes to multiple aspects: first, it examined the impact of ownership structure and board characteristics on firm performance. Second, the moderating effect of board gender and board ethnic diversity contributes to research significant and valuable for the researchers and practitioners. Finally, the study employed S-GMM, controlling for dynamic endogeneity considered a main econometric problem for CG-performance relationships.

This paper aims to develop a novel grey Bernoulli model with memory characteristics, which is designed to dynamically choose the optimal memory kernel function and the length of memory dependence period, ultimately enhancing the model's predictive accuracy.

This paper enhances the traditional grey Bernoulli model by introducing memory-dependent derivatives, resulting in a novel memory-dependent derivative grey model. Additionally, fractional-order accumulation is employed for preprocessing the original data. The length of the memory dependence period for memory-dependent derivatives is determined through grey correlation analysis. Furthermore, the whale optimization algorithm is utilized to optimize the cumulative order, power index and memory kernel function index of the model, enabling adaptability to diverse scenarios.

The selection of appropriate memory kernel functions and memory dependency lengths will improve model prediction performance. The model can adaptively select the memory kernel function and memory dependence length, and the performance of the model is better than other comparison models.

The model presented in this article has some limitations. The grey model is itself suitable for small sample data, and memory-dependent derivatives mainly consider the memory effect on a fixed length. Therefore, this model is mainly applicable to data prediction with short-term memory effect and has certain limitations on time series of long-term memory.

In practical systems, memory effects typically exhibit a decaying pattern, which is effectively characterized by the memory kernel function. The model in this study skillfully determines the appropriate kernel functions and memory dependency lengths to capture these memory effects, enhancing its alignment with real-world scenarios.

Based on the memory-dependent derivative method, a memory-dependent derivative grey Bernoulli model that more accurately reflects the actual memory effect is constructed and applied to power generation forecasting in China, South Korea and India.

The relationship between real exchange rate and services export diversification is at the heart of this study.

The analysis is performed using a sample of 113 countries over the period 1985–2014, and the 2-step system Generalized Method of Moments (GMM) approach. The analysis uses both the Theil index and Herfindahl–Hirschman index of services export concentration.

The analysis shows that over the full sample, the real effective exchange rate appreciation induces a greater services export diversification. This outcome applies to high-income countries and developing countries. However, the positive effect of the appreciation of the real exchange rate on services export concentration is lower in least developed countries than in other countries. Finally, the effect of the appreciation of the real exchange rate on services export concentration in tax haven countries depends on the indicator of services export concentration, as this is positive for the Theil index and negative for the Herfindahl–Hirschman index of services export concentration.

These findings highlight the strong influence of real exchange policies on countries' path of services export diversification.

To the best of the authors' knowledge, this topic is being addressed in the empirical literature for the first time.

Rule of law is essential in reducing corruption in a country. This study aims to investigate the factors contributing to corruption in 41 of the most competitive countries in the Asia-Pacific region by focusing on judicial effectiveness, property rights and government integrity. The moderating role of regulatory quality was also considered in the attempt to explain the association among rule of law and corruption.

This study used pooled ordinary least squares regression and generalized method of moments-dynamic panel for the robustness test on data of 41 Asia-Pacific countries spanning from 2013 to 2021.

Property rights and government integrity were found to be negatively significant in explaining corruption. In contrast, the interaction between rule of law and regulatory quality had a significant positive association with corruption. The findings bring to light Asia-Pacific countries’ need for more effective control of corruption.

The authorities should work towards enhancing the countries’ image as corruption-free nations by creating a stable economic and political environment and preserving macroeconomic stability through strengthened rule of law.

Previous research looked at The Association of Southeast Asian Nations and South Asian countries, but little attention was given to Asia-Pacific countries in examining the relationship between rule of law and corruption.