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The purpose of this paper is to provide a solution for natural convection in a cavity with a partial heater in case of volumetric heating and analysis of the entropy generation.

The control volume method based on three-dimensional (3D) vorticity-potential vector was applied to solve governing equations of natural convection in a 3D cavity with a fin for different governing parameters as external Rayleigh numbers (103=Ra_E=106), internal Rayleigh numbers 103=Ra_I=106, partition height (0.25=h=0.75) and partition location (0.25=c=0.75). A code was written by using Fortran platform.

The edge of the fin becomes important on entropy generation. The ratio of the Ra_I/Ra_E plays the important role on natural convection and entropy generation. The variation of external Rayleigh number becomes insignificant for the Ra_I/Ra_E>1.

The originality of this work is to analyze the entropy generation and natural convection in a cubical cavity with volumetrically heating.

This paper examined the evaluation of the virtual internship program for KAU IT students during the COVID-19 pandemic, 2020 summer.

A mixed-method survey was utilized for the data collection. Out of 164 enrolled students in the 2020 summer training program, 147 students opted to participate. This gives a response rate of 89.6% of the total students' number who could participate. In addition to collecting quantitative data, qualitative data were collected. The sources for qualitative data were survey open questions, weekly reflective writing and video recordings.

The quantitative result showed that the students were satisfied with their virtual internship. These results were further qualitatively explored and discussed under five themes: information and knowledge, work experience, live interaction, the comfort of achieving tasks and soft skills. The outcomes showed that the plan which offered students opportunities to be trained online with real companies accomplishing real work tasks was the best in fulfilling the requirements of the internship. Thus, it emphasized the importance of a strong alliance with the industry to provide useful virtual internship opportunities.

Though this study made a novel contribution to the timely literature on the COVID-19 pandemic, it is not without its limitations. The difference in the three sample sizes makes it difficult to get in-depth comparative analysis. For future research, it is highly recommended to study the impact of online training with real existing companies on a relatively larger sample number.

In order for a higher educational institute to successfully adopt the proposed plans for the virtual internship, here are the reflections and lessons learned from our three plans. (1) Emphasize your efforts on extending your partnership with the private sector and computing industry. (2) The MCIT training focuses on developing technical skills; therefore, it is great to be offered to students in the computing field as extracurricular activities but not as the fulfillment of the internship program. (3) Blackboard training sessions, which cover nontechnical skills, are good to be offered prior to the internship.

For governmental human resource agencies, it is highly recommended to further develop and invest in manpower to develop online platforms. In normal situations, these platforms act as an extra training resource. In abnormal situations such as the COVID-19 pandemic, they act as useful source for online training. For students, this sudden unexpected transition from normal to online training should enrich them with the ability to be flexible and adaptive, tune them with opportunities for independent and innovative creative work, encourage them to take risks and provide them with opportunities to do things differently. As an outcome, students will enhance their self-efficacy and capabilities.

Due to the COVID-19 pandemic, not only classes and internship programs have been done remotely but increasingly jobs have also gone in that direction. A virtual internship today might be good preparation for the virtual/remote work of tomorrow. For this reason, this study was conducted to add a novel contribution to the virtual internship literature.

The main purpose of this work is the development of a numerical algorithm based on modified cubic trigonometric B-spline functions for computational modelling of hyperbolic-type wave equations. These types of equations describe a variety of physical models in the vibrations of structures, nonlinear optics, quantum field theory and solid-state physics, etc.

Dirichlet boundary conditions cannot be handled easily by cubic trigonometric B-spline functions. Then, a modification is made in cubic trigonometric B-spline functions to handle the Dirichlet boundary conditions and a numerical algorithm is developed. The proposed algorithm reduced the hyperbolic-type wave equations into a system of first-order ordinary differential equations (ODEs) in time variable. Then, stability-preserving SSP-RK54 scheme and the Thomas algorithm are used to solve the obtained system. The stability of the algorithm is also discussed.

A different technique based on modified cubic trigonometric B-spline functions is proposed which is quite different from the schemes developed (Abbas et al., 2014; Nazir et al., 2016) and depicts the computational modelling of hyperbolic-type wave equations.

To the best of the authors’ knowledge, this technique is novel for solving hyperbolic-type wave equations and the developed algorithm is free from quasi-linearization process and finite difference operators for time derivatives. This algorithm gives better results than the results discussed in literature (Dehghan and Shokri, 2008; Batiha et al., 2007; Mittal and Bhatia, 2013; Jiwari, 2015).

This chapter examines how innovation and research are essential to the advancement of science, the economy, and society. We examine the current status of scientific research in Saudi Arabia, highlighting issues like financial limitations and a lack of skilled researchers. We emphasize how important it is to develop the next generation of scientists in order to transform existing practices and improve the state of scientific research in the country.

Proficiency in research and innovation is crucial for expanding the frontiers of knowledge, empowering scientists to tackle intricate problems, and advancing scientific rigor. These abilities also support the use of evidence in decision-making, enabling researchers to provide empirical data that inform practices and policies in a variety of industries. Sustained growth requires the formation of future leaders, who promote knowledge exchange and multidisciplinary collaboration.

Despite Saudi Arabia’s significant spending on science, problems still exist. Addressing governance deficiencies is demonstrated by the establishment of the Research, Development, and Innovation Authority in 2021. The nation has grown in the world’s scientific rankings, drawing eminent specialists and fostering cross-border cooperation. Still, there is room for improvement, especially when it comes to fostering a culture of research, improving financing sources, and encouraging international collaboration. It is imperative that these problems are resolved in order to avoid stagnation, guarantee ongoing innovation, and take advantage of chances for society’s progress.

The chapter ends with a call to action that highlights how quickly improvements must be made. Failing to do so runs the risk of stifling the advancement of science, preventing the creation of new technologies, and prolonging complicated issues. To lower risks, seize opportunities, and ensure that research and innovation continue to advance for the good of society, immediate action is necessary.

The purpose of this study is to investigate the effect of roselle flower extract and date palm pollen on the nutritional and sensory qualities of date palm spathe beverage (DPSB).

The nutritional composition and sensorial quality of the date palm spathe-based beverage were evaluated. The product was fortified with different concentrations (1 per cent and 5 per cent) of roselle flowers and 1 per cent date palm pollen grains.

Generally, fortification of the DPSB with roselle flowers only or the combination of roselle flowers and date palm pollen grains significantly affected the nutritional and sensory properties of the products. The total dissolved solids, turbidity and total contents of proteins; fats; carbohydrates; vitamins A, E and C; iron; nickel and copper were highest in the DPSB fortified with a mixture of 1 per cent roselle flower extract and 1 per cent pollen grains and lowest in the DPSB supplemented with 1 per cent roselle flower extract. The manganese and selenium contents were both highest and lowest in DPSB supplemented with 5 per cent and 1 per cent roselle flower extract, respectively. Antioxidant activity was highest in DPSB supplemented with the 5 per cent roselle flower extract and lowest in unfortified DPSB. Boron, molybdenum and zinc contents were highest in unfortified DPSB. All sensory attributes were highest in both the unfortified DPSB and that fortified with 1 per cent roselle flower extract.

While fortification with a combination of 1 per cent roselle flower extract and 1 per cent date palm pollen grains improved the nutritional quality of the DPSB, it negatively affected the sensory attributes of the products.

This paper aims to consider the heat transportation together with irreversibility analysis for the flow of couple stress hybrid nanofluid past over a stretching surface. The innovative characteristics of this paper include electro-magnetohydrodynamic (EMHD) term, viscous dissipation, Joule heating and heat absorption\omission. The hybrid nanofluid is prepared due to the suspension of the solid nanoparticles of the single wall and multi-wall carbon nanotubes (SWCNTs and MWCNTs) in the blood for the testing purpose of heat transfer and drug deliveries. The experimental value of the Prandtl number used for the blood is 21 from the available literature and very large as compared to the Prandtl number of the other base fluids. Appropriate transformations are incorporated to convert the modeled partial differential equations into the nonlinear ordinary differential equations. The homotopy analysis method (HAM) is used to obtain the solution. The explanation for velocity, energy and entropy are exposed under the influence of various parameters such as E, M, k, Q, S and Ec. The numerical values are calculated and summarized for dimensionless Cf and Nu.

In this investigation, heat transportation together with irreversibility analysis for the flow of couple stress hybrid nanofluid past over a stretching surface is considered. The innovative characteristics of this paper include EMHD term, viscous dissipation, Joule heating and heat absorption\omission. The hybrid nanofluid is prepared due to the suspension of the solid nanoparticles of the SWCNTs and MWCNTs in the blood for the testing purpose of heat transfer and drug deliveries. The experimental value of the Prandtl number used for the blood is 21 from the available literature and very large as compared to the Prandtl number of the other base fluids. Appropriate transformations are incorporated to convert the modeled partial differential equations into the nonlinear ordinary differential equations. The HAM is used to obtain the solution. The explanation for velocity, energy and entropy are exposed under the influence of various parameters such as E, M, k, Q, S and Ec. The numerical values are calculated and summarized for dimensionless Cf and Nu.

The explanation for velocity, energy and entropy are exposed and the flow against various influential factors is discussed graphically. The numerical values are calculated and summarized for dimensionless In addition, the current study is compared for various values of to that published literature and an impressive agreement in terms of finding is reported. It has also been noticed that the and factors retards the hybrid nanofluid flow, while the temperature of fluid becomes upsurges by the rise in these factors.

This is examined while evaluating the previously discussed publications that study on EMHD aspects of magnetized Casson type hybrid nanofluid via entropy generation research is innovative but also acknowledging that the couple stress model challenged bilaterally on stretching surface has not yet been studied. So, there is an ongoing attempt to bridge such a space.

Mobile edge computing (MEC) services have long been used by private enterprises in Saudi Arabia with considerable success; however, there has been a stark lack of insight into how these services can be used to improve mobile government (M-Government) services for KSA citizens. This study aims to bridge this gap by integrating MEC with an enhanced version of the technology acceptance model (TAM) and examining its effects on user behavior and acceptance.

A closed-ended survey was administered to 1,500 people, and the responses were analyzed using sophisticated advanced statistical techniques to test an expanded TAM, using a quantitative method that uses structural equation modeling to validate the proposed model and hypotheses.

This study reveals that MEC significantly influences users’ intentions about using M-Government services and their tolerance for new technology adoption. Specifically, service cost and social influence are positively linked with end users’ intention to adopt M-Government services.

The novelty and contribution of this paper to existing literature are in highlighting the pivotal role of MEC in transforming public sector service delivery through technology. This study not only supports the adoption of M-Government services to enhance social welfare but also demonstrates and concludes some practical and theoretical ramifications of MEC service adoption.

Three main objectives of this study were as follows: (1) To estimate the prevalence rate of post-traumatic stress disordered (PTSD) symptoms among Saudi paramedics, (2) To investigate which types of coping strategies were associated with PTSD symptoms among Saudi paramedics, (3) To explore which sources of social support were associated with PTSD symptoms among Saudi paramedics.

Data were collected from 217 paramedics working in the Saudi Red Crescent Authority from September to December 2019. Participants completed questionnaires measuring PTSD symptoms (the Screen of Post-Traumatic Stress Disorders; SPTSD), passive and active coping strategies (Brief COPE Scale; BC), and three forms of social support: support from friends, family and organizational support. Associations between coping strategies, social support and PTSD symptoms were investigated using correlational analyses, hierarchical linear regression and binary logistic regression.

46% of participants experienced one or more PTSD symptom, 28.6% scored above the cut-off for partial PTSD and 17.5% scored above the cut-off for full PTSD. PTSD symptoms were significantly positively correlated with passive coping and negatively associated with both family and friends support. Passive coping was positively associated with a greater risk of meeting criteria for PTSD.

The current findings suggest that interventions to help reduce PTSD in Saudi paramedics should include strategies to reduce passive coping. Future research is urgently required to help understand the psychological, social and work-related factors that contribute to these high levels of PTSD.

To improve the thermal performance of base fluid, nanoparticles of three types are dispersed in the base fluid. A novel theory of non-Fourier heat transfer is used for design and development of models. The thermal performance of sample fluids is compared to determine which types of combination of nanoparticles are the best for an optimized enhancement in thermal performance of fluids. This article aims to: (i) investigate the impact of nanoparticles on thermal performance; and (ii) implement the Galerkin finite element method (GFEM) to thermal problems.

The mathematical models are developed using novel non-Fourier heat flux theory, conservation laws of computational fluid dynamics (CFD) and no-slip thermal boundary conditions. The models are approximated using thermal boundary layer approximations, and transformed models are solved numerically using GFEM. A grid-sensitivity test is performed. The accuracy, correction and stability of solutions is ensured. The numerical method adopted for the calculations is validated with published data. Quantities of engineering interest, i.e. wall shear stress, wall mass flow rate and wall heat flux, are calculated and examined versus emerging rheological parameters and thermal relaxation time.

The thermal relaxation time measures the ability of a fluid to restore its original thermal state, called thermal equilibrium and therefore, simulations have shown that the thermal relaxation time associated with a mono nanofluid has the most substantial effect on the temperature of fluid, whereas a ternary nanofluid has the smallest thermal relaxation time. A ternary nanofluid has a wider thermal boundary thickness in comparison with base and di- and mono nanofluids. The wall heat flux (in the case of the ternary nanofluids) has the most significant value compared with the wall shear stresses for the mono and hybrid nanofluids. The wall heat and mass fluxes have the highest values for the case of non-Fourier heat and mass diffusion compared to the case of Fourier heat and mass transfer.

An extensive literature review reveals that no study has considered thermal and concentration memory effects on transport mechanisms in fluids of cross-rheological liquid using novel theory of heat and mass [presented by Cattaneo (Cattaneo, 1958) and Christov (Christov, 2009)] so far. Moreover, the finite element method for coupled and nonlinear CFD problems has not been implemented so far. To the best of the authors’ knowledge for the first time, the dynamics of wall heat flow rate and mass flow rate under simultaneous effects of thermal and solute relaxation times, Ohmic dissipation and first-order chemical reactions are studied.

The purpose of this paper is to empirically examine the effect of royal family members on firm performance of publicly listed companies in Saudi Arabia.

Using 491 firm-year observations of non-financial publicly listed firms in Saudi Arabia’s stock market between 2009 and 2013, the study employs, besides others, the advanced econometric technique GMM-system estimator. This allows the dynamic nature and control of the endogeneity problem to be accounted for in corporate governance and firm performance.

The main result is that the attendance of royal family members at board meetings negatively influences firm performance but does not have an influence on firm value. The results also show that firms with many independent royal family members on the board of directors have better firm performance and firm value. In addition, firms with a high number of royal family members presenting on the board have better firm performance.

This study offers guidance to assist the further investigation of the SA Royal Family’s BoD membership either in SA or in other monarchy countries. It is interesting to compare these results in order to further understand the different effects that the Royal Family’s BoD membership have in such countries. This study’s results suggest that independent members of SA’s Royal Family on the BoD have some influence on firm performance in both the short and long term. Thus, policymakers should encourage the members of SA’s Royal Family to become more involved in firms’ BoDs.

This study offers guidance for further investigation of royal family members in the region or in other monarchy countries. It will be interesting to compare these results. The study suggests that royal family members on the board have a partial influence on firm performance, especially the independent ones. Thus, the policymakers should encourage more involvement of independent royal family members on the board.

Foreign and minority investors, who invest in SA’s publicly listed firms, should note that when independent members of SA’s Royal Family are on the BoD their investment will benefit from the reduced risks and uncertainty.

To the best of the author’s knowledge, this is the first study undertaken to investigate empirically the influence a royal family’s presence on the board of directors has on firm performance. This study is based on both theories, namely the agency theory and resource dependence theory.