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Ti6Al4V alloy has received a great deal of attention in medical applications due to its biomechanical compatibility. However, the human bone stiffness is between 10 and 30 GPa while solid Ti6Al4V is several times stiffer, which would cause stress shielding with the surrounding bone, which can lead to implant and/or the surrounding bone’s failure.

In this work, the effect of selective laser melting (SLM) process parameters on the characteristics of Ti6Al4V samples, such as porosity level, surface roughness, elastic modulus and compressive strength (UCS), has been investigated using response surface method. The examined ranges of process parameters were 35-50 W for laser power, 100-400 mm/s for scan speed and 35-120 µm for hatch spacing. The process parameters have been optimized to obtain structures with properties very close to that in human bones.

The results showed that the porosity percentage of a SLM component could be increased by reducing the laser power and/or increasing the scan speed and hatch spacing. It was also shown that there was a reverse relationship between the porosity level and both the modulus of elasticity and UCS of the SLM part. In addition, the increased laser power was resulted into a substantial decrease of the surface roughness of SLM parts. Results from the optimization study revealed that the interaction between laser process parameters (i.e. laser power, laser speed, and the laser spacing) have the most significant influence on the mechanical properties of fabricated samples. The optimized values for the manufacturing of medical implants were 49 W, 400 mm/s and 99 µm for the laser power, laser speed and laser spacing, respectively. The corresponding porosity, surface roughness, modulus of elasticity and UCS were 23.62 per cent, 8.68 µm, 30 GPa and 522 MPa, respectively.

Previous investigations related to additive manufacturing of Ti alloys have focused on producing fully dense and high-integrity structures. There is a clear gap in literature regarding the simultaneous enhancement and adjustment of pore fraction, surface and mechanical properties of Ti6Al4V SLM components toward biomedical implants. This was the objective of the current study.

The purpose of this study is to estimate the linear regression parameters using two alternative techniques. First technique is to apply the generalized linear model (GLM) and the second technique is the Markov Chain Monte Carlo (MCMC) method.

In this paper, the authors adopted the incurred claims of Egyptian non-life insurance market as a dependent variable during a 10-year period. MCMC uses Gibbs sampling to generate a sample from a posterior distribution of a linear regression to estimate the parameters of interest. However, the authors used the R package to estimate the parameters of the linear regression using the above techniques.

These procedures will guide the decision-maker for estimating the reserve and set proper investment strategy.

In this paper, the authors will estimate the parameters of a linear regression model using MCMC method via R package. Furthermore, MCMC uses Gibbs sampling to generate a sample from a posterior distribution of a linear regression to estimate parameters to predict future claims. In the same line, these procedures will guide the decision-maker for estimating the reserve and set proper investment strategy.

This paper focuses on a project to work on the digital library of Arab children's culture for sustainable development (DLACSD).

This project claims to link the past, present, and future by creating a platform that can grow to include not only works by adults but by children who inspire adults with their imagination and the joys they bring to the world.

This project addresses in phases the different aspects of the problem of the lack of material for Egyptian/Arab children at different stages in Arabic on the internet (with copyright law in mind). It is time to fill this gap by having a rich repository of stories, plays, games and songs for children in Arabic in a digital library to enrich the life of the child and to inform the world that much that is worthwhile is available in Arabic for parents, teachers, and children to enjoy.

Through reading samples of the works by Abdel-Tawab Youssef (1928–2015) by using the Dublin Core Elements, it will be informative to see how his writings address the United Nations Goals of Sustainable Development way before these Goals were discussed.

Writers for children, librarians, teachers, psychologists, literary critics, illustrators, and parents need a platform that makes material available to promote children’s culture in the Arab world and to introduce the world to what is of value for children in Arabic.

Currently, communication brings the world together and although the social media and the new technology have introduced problems that are serious, to say the least, collaborators on all levels must play an active role in redressing the social wrongs, especially those affecting children.

This ongoing project by members of a team who believe in interdisciplinarity and multidisciplinarity has taken the first step to create and develop (DLACSD).

Residing in a densely populated urban area possesses its allure; nonetheless, it can significantly impact physical and mental well-being owing to the persistent stress and information overload inherent in urban settings. This study aims to introduce a neuro-urbanism framework that can guide urban planners and designers in quantitatively evaluating individuals' responses to virtual simulated environments.

Our study consisted of two phases after randomly selecting six locations representing three types of urban areas in Bratislava, Slovakia: urban spaces, urban streets, and public parks. First, we conducted a Mentimeter live polling (dialogic survey fusion), followed by an experiment involving volunteer participants from the Slovak University of Technology. This experiment employed an electroencephalogram (EEG) with virtual reality headsets to virtually explore participants' responses to the selected locations.

The EEG signal analysis revealed significant differences in relaxation levels across the selected locations in this study. Urban streets with commercial activities promote mental well-being more effectively than public parks, challenging the preconception that restorative environments are exclusively confined to public parks.

The results demonstrate a replicable neuro-urbanism framework comprising three distinct stages: problem-based technology rooted in neuroscience, experimental setup and deliverables, and identification of restorative environments.

In today's highly competitive and customer oriented business environment, business firms in all sectors are looking for ways to improve customer satisfaction. In this context, textile firms are no exception. This research simulates the actual operations of a textile firm in order to show the impact of sequencing operational rules on the ability of the firm to improve its responsiveness to customers.

Using turbulators, obstacles, ribs, corrugations, baffles and different tube geometry, and also various arrangements of these components have a noticeable effect on the shell and tube heat exchangers (STHEs) thermal-hydraulic performance. This study aims to investigate non-Newtonian fluid flow characteristics and heat transfer features of water and carboxyl methyl cellulose (H₂O 99.5%:0.5% CMC)-based Al₂O₃ nanofluid inside the STHE equipped with corrugated tubes and baffles using two-phase mixture model.

Five different corrugated tubes and two baffle shapes are studied numerically using finite volume method based on SIMPLEC algorithm using ANSYS-Fluent software.

Based on the obtained results, it is shown that for low-mass flow rates, the disk baffle (DB) has more heat transfer coefficient than that of segmental baffle (SB) configuration, while for mass flow rate more than 1 kg/s, using the SB leads to more heat transfer coefficient than that of DB configuration. Using the DB leads to higher thermal-hydraulic performance evaluation criteria (THPEC) than that of SB configuration in heat exchanger. The THPEC values are between 1.32 and 1.45.

Using inner, outer or inner/outer corrugations (outer circular rib and inner circular rib [OCR+ICR]) tubes for all mass flow rates can increase the THPEC significantly. Based on the present study, STHE with DB and OCR+ICR tubes configuration filled with water/CMC/Al₂O₃ with f = 1.5% and d_np = 100 nm is the optimum configuration. The value of THPEC in referred case was 1.73, while for outer corrugations and inner smooth, this value is between 1.34 and 1.57, and for outer smooth and inner corrugations, this value is between 1.33 and 1.52.

The purpose of this study is to evaluate the effectiveness of nanocontainer solutions in removing deteriorated and aged polymers commonly used in coating and consolidating archaeological glass.

This study focused on characterizing glass surfaces coated with two commonly used polymeric materials in archaeological glass preservation. Furthermore, the study evaluates the elimination of these coatings from the surfaces by using innovative aqueous systems composed of micellar solutions (MS) and oil-in-water (O/W) Texapon-P microemulsions (TEX). Glass samples coated with selected polymers were subjected to thermal and photochemical aging to simulate natural degradation conditions. This study aimed to evaluate the effectiveness of nanocontainer aqueous systems compared to acetone (Ac), a conventional solvent commonly used for removal procedures. The characterization procedures involved transmission electron microscopy, USB digital microscopy, scanning electron microscopy, color alteration and gravimetric measurement.

The findings indicate that the effectiveness of novel techniques using aqueous nanocontainer systems is quite promising when considering a “green approach” to preserving cultural heritage. Microscopic examination demonstrated the efficacy of MS in effectively removing acrylic and vinyl polymers from the glass surface. Furthermore, TEX proved effective in removing polyvinyl acetate (PVA) over Paraloid B72 (B-72). In addition, the measurement of color alteration values revealed a decrease after using MS compared to the standard sample before applying the polymers, with values of ΔE = 1.48 and 1.82 for B-72 polymer and PVA, respectively.

This research provides nanocontainer solutions for removing aged polymers from the glass surface. This makes the current study a promising step for treating archaeological glass.

The purpose of this paper is to investigate the effect of corporate governance (CG) mechanisms (board size, board independence, separation of chairman and chief executive officer (CEO) roles and external auditor type) on accounting conservatism in Egypt.

Archival data relating to CG and accounting conservatism are collected and analysed using multivariate regression techniques.

The findings indicate that board independence is positively associated with accounting conservatism. By contrast, board size and auditor type are negatively associated with accounting conservatism, while separating the chairperson and CEO roles has no significant relationship with accounting conservatism.

To the best of the author’s knowledge, this is one of the first empirical attempts at providing evidence on the relationship between CG and accounting conservatism in Egypt.

This study aims to examine the role of the board of directors in affecting earnings management practices across small- and medium-sized enterprises (SMEs) life cycle.

Data is collected from 280 SMEs listed on the London Stock Exchange during the period of 2009–2016. Fixed effects regression analysis is used to test the hypotheses.

This study shows that the impact of the board of directors' roles on earnings management practices varies depending on the SMEs life cycle stage. In the introduction, growth and decline stages of SMEs, the wealth creation role of the board is negatively significant with earnings management, while the wealth protection role of the board is positively significant in the growth and maturity phases. Results suggest that the board's responsibility to create wealth deters early-stage earnings management strategies, while protecting shareholder interests, in latter stages, leads to a decrease in earnings management.

The findings suggest that corporate governance should be customized to the specific stage of the SMEs life cycle. Additionally, different life cycle stages may impose different requirements on corporate boards to shape the effectiveness of these mechanisms and constrain earnings management practices.

To the best of the authors’ knowledge, this study offers one of the first insights on the UK SMEs to understand how board functions and earnings management practices vary over SMEs life cycles. It will offer important information on the effect of board features on earnings management in SMEs in the UK and is anticipated to be of importance to policymakers, regulators, investors and practitioners.