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The purpose of this paper is to present an implementation of a soft‐computing (SC) based navigation approach on a bi‐steerable mobile robot, Robucar. This approach must provide Robucar with capability to acquire the obstacle avoidance, target localization, decision‐making and action behaviors after learning and adaptation. This approach uses three neural networks (NN) and fuzzy logic (FL) controller to achieve the desired task. The NNs corresponding to the obstacle avoidance and target localization are trained using the back‐propagation algorithm and the last one is based on the reinforcement learning paradigm while the FL controller uses the Mamdani search and match algorithm. Simulation and experimental results are presented, showing the effectiveness of the overall navigation control system.

In this paper, an interesting navigation approach is applied to a car‐like robot, Robucar, with addition of an action behavior to deal with the generation of smooth motions. Indeed, this approach is based on four basic behaviors; three of them are fused under a neural paradigm using Gradient Back‐Propagation (GBP) and reinforcement learning (RL) algorithms and the last behavior uses a FL controller. It uses a set of suggested rules to describe the control policy to achieve the action behavior.

In the implemented SC‐based navigation, the intelligent behaviors necessary to the navigation are acquired by learning using GBP algorithm and adaptation using FL. The proposed approach provides Robucar with more autonomy, intelligence and real‐time processing capabilities. Indeed, the proposed NNs and FLC are able to remedy problems of analytical approaches, missing or incorrect environment knowledge and uncertainties which can lead to undesirable effects as the rough velocity changes. The simulation and experimental results display the ability of the proposed SC‐based navigation approach to provide Robucar with capability to intelligently navigate in a priori unknown environment, illustrating the robustness and adaptation capabilities of the approach.

This work can be extended to consider mobile obstacles with a velocity higher than the velocity of the robot.

This paper presents a learning approach to navigating a bi‐steerable mobile robot in an unknown environment using GBP and RL paradigms.

In order to achieve substantial growth of VFP's hydraulics systems business at home and overseas, Richard Jasinski (38) has been appointed sales & marketing director and assistant managing director of VFP Fluid Power Ltd of Swindon, Wiltshire, a subsidiary of Aerospace Engineering plc.

The purpose of this paper is to study chemical reaction and heat and mass transfer effects on steady free convection flow in an inclined porous plate in the presence of MHD and viscous dissipation through the application of scaling group of transformation and numerical method.

The fourth-order Runge-Kutta along with the shooting method is employed in the numerical solution of the governing equations.

The magnetic field parameter, the permeability of porous medium and the viscous dissipation are demonstrated to exert a more significant effect on the flow field and, thus, on the heat transfer from the plate to the fluid.

The problem is relatively original.

This paper aims to present the design and implementation of a new general-purpose single-phase buck-type inverter.

The operation of the proposed inverter is based on the general-purpose buck converter. The proposed buck-type inverter topology is designed with reduced numbers of passive and active elements to minimize design cost and complexity. Also, an efficient hybrid control technique based on the proportional‐integral‐derivative (PID) supported by open-loop control signal is offered for the control of the proposed inverter. The proposed hybrid control method improves the performance of the PID controller during the change of inverter operation parameters. A close to single-phase sine wave output voltage with low total harmonic distortion (THD) can be produced by the proposed inverter in a wide range of voltage and frequency lower than the inverter input voltage value.

Simulation and experimental test studies are applied to the proposed inverter. The experimental laboratory setup is built for 0–50 Hz, 0–100 Vp, 0.5 kW. Both the simulation and the experimental test results show that the single-phase inverter can produce close to sine wave output voltage with THD level under 5% in a wide range of frequency for various operating conditions and for different loads.

In this paper, a new topology and a new hybrid control technique that are patented by the corresponding author are implemented for a single-phase buck-type inverter through a scientific project. The operating results of the study reveal the efficient operating capability with a simple topology structure.

This study utilizes cultural values from the World Values Survey (WVS) to investigate the cultural hypothesis regarding economic growth. Following Granato et al.'s (1996) theory, this paper describes a systematic method for developing analytical models that clarify the effect of cultural values on economic growth by using seemingly unrelated regression (SUR).

The results are sustained through regression analysis using ordinary least squares (OLS) and SUR. The sample size covers all WVS countries from the third wave in 1994 to the seventh wave in 2021, due to the limited sample size in the first and second surveys, which is insufficient for estimation.

Results highlight culture as a crucial factor for economic growth. Although the study found a positive effect of autonomy, life satisfaction, and post-materialism on economic growth, trust has been found to have a negative impact.

Although the literature has theoretically proven the impact of cultural values on economic growth, there is a significant disparity in the empirical studies, owing to a lack of applied studies. This study deepens the cultural analysis compared to earlier empirical investigations. To the best of the authors' knowledge, this is the first attempt to assess the combined effect of the selected four cultural values on economic growth during 1994 and 2021. Furthermore, SUR analysis allows for the estimation of the variables' effects throughout the five waves.

The purpose of this paper is to present a model to predict the micro-hardness of friction stir processed (FSPed) AZ31B magnesium alloy using response surface methodology (RSM). Another objective is to identify process parameters and through-thickness position which will give higher micro-hardness values. Moreover, the study aims at defining the factor that exhibits the most effect on the micro-hardness. Friction stir processing (FSP) machine can then be fed with the optimized parameters to achieve desirable properties.

An experimental setup was designed to conduct FSP. Several AZ31B magnesium samples were FSPed at different combinations of rotational and translational speeds. The micro-hardness of all the combinations of process parameters was measured at different through-thickness positions. This was followed by an investigation of the three factors on the resulting micro-hardness. RSM was then used to develop a model with three factors and three levels to predict the micro-hardness of FSPed AZ31 magnesium alloy within the covered range. The analyses of variance in addition to experimental verification were both used to validate the model. This was followed by an optimization of the response.

The model showed excellent capability of predicting the micro-hardness values as well as the optimum values of the three factors that would result in better micro-hardness. The model was able to capture the effects of rotational speed, translational speed, and through-thickness position. Results suggest that micro-hardness values were mostly sensitive to changes in tool rotational speed.

FSP is considered to be one of the advanced microstructural modification techniques which is capable of enhancing the mechanical properties of light-weight alloys. However, the lack of accurate models which are capable of predicting the resulted properties from process parameters hinders the widespread utilization of this technique. At the same time, RSM is considered as a vital branch of experimental design due to its ability to develop new processes and optimize their performance. Hence, the developed model is very beneficial and is meant to save time and experimental effort toward effective use of FSP to get the desired/optimum micro-hardness distribution.

There is much debate in the literature about how the performance of Islamic banks (IBs) should be measured. Basically, IBs’ business models are different from that of conventional banks; thus, the performance of IBs should be measured by using a Sharīʿah-based approach. This paper considers zakat (Islamic tax) as an alternative indicator to measure the performance of IBs. This paper aims to examine whether zakat ratios can be used as Islamic performance (ISPER) indicators for IBs besides the conventional performance (COPER) indicators.

The investigation covered a sample of 214 yearly observations of 37 IBs located in Indonesia, Malaysia, Bahrain, Saudi Arabia and the United Arab Emirates for the period 2007–2015. This study used a single-factor congeneric model and confirmatory factor analysis, performed using the AMOS 23.0 software.

The findings assert that the discriminant validity of multi-bank performance, as measured by ISPER [zakat on assets (ZOA) and zakat on equity (ZOE)] and COPER indicators (return on assets, return on equity and operational efficiency in terms of assets), is very high. Hence, ISPER and COPER measurements are valid, either together to measure the multi-performance of IBs from both the Islamic and conventional perspectives, or independently as each measurement is valid to measure the Islamic and conventional performance if it is used separately.

This paper does not investigate whether the findings are constant across time. This represents one of the limitations of this study.

It is strongly recommended that IBs calculate and disclose zakat ratios, particularly ZOA and ZOE, in their annual reports. Researchers and academicians should use these ratios for measuring the ISPER of IBs, either along with COPER or separately.

Empirical evidence is provided in this paper on the development and validity of zakat ratios as ISPER indicators in the Islamic banking industry. Zakat ratios are suitable indicators that can measure IBs’ performance and achieve the goals of IBs as well as those of Islamic economics. Technically, zakat has a dynamic ability to reflect the profitability of IBs. The more the IBs generate profit, the more they pay zakat. Furthermore, the greater the total assets of IBs, the higher the amount of zakat that they should pay. Thus, zakat ratios can be used as profitability measurements as in the case of tax ratios.

Corporate corruption reporting (CCR) is an emerging issue of the corporation for measuring transparency, integrity and accountability to the stakeholders and society. The purpose of this paper is to examine the role of CCR and financial management responsibility regarding the issue of corruption control.

To explore the influences of corruption disclosure, this study considers the keywords-based content analysis of the listed financial firms of the Dhaka Stock Exchange in Bangladesh for 2012–2016. The research considers stakeholders and theoretical legitimacy lens for discussing corporate corruption disclosure. This study identified 143 self-driven keywords by classifying, analyzing and selecting the appropriate large set of keywords from the prior literature. This study examines 247 firm-year observations of all financial firms in Bangladesh using secondary data sources.

The results of the hierarchical regression analysis report that financial firms following Sharia principles have a negative and significant association with CCR, while Big4 has a positive and significant influence. Moreover, the interaction effect of Big4 on the relationship between Sharia principles and CCR is negative and insignificant. The findings reported that Islamic financial firms disclose less corruption information than conventional financial firms in Bangladesh.

This study findings are expected to significantly impact corporate management and policymakers of developing and highly corrupted economies to enhance corporate accountability, transparency and reputation. The regulatory body can consider the findings to promulgate anti-corruption reporting rules and regulations.

The authors believe the theoretical lens used to support the method and findings of this paper are unique and novel.

The paper concentrates on the administrative side of the United Arab Emirates (UAE) budgetary process and employs a quantitative approach to test two major hypotheses about the style of decision making and the impact of this style on annual estimations of public expenditures. Therefore, the major question of the paper is not concerned with the content of these decisions (annual estimations) in a substantive descriptive and normative manner, as in public finance studies, but rather with the analysis of the outcomes of these decisions. The paper uses data from annual budgetary allocations to test certain hypotheses and concludes that UAE budgetary decision-makers in United Arab Emirates Federal ministries use an incremental style of decision making to estimate their annual expenditure.