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This study aims to determine the reliability assessment based on the predicted fatigue life of leaf spring under random strain loading.

Random loading data were extracted from three various road conditions at 200 Hz using a strain gauge for a duration of 100 s. The fatigue life was predicted using strain-life approaches of Coffin–Manson, Morrow and Smith–Watson–Topper (SWT) models.

The leaf spring had the highest fatigue life of 1,544 cycle/block under highway data compared uphill (1,299 cycle/block) and downhill (1,008 cycle/block) data. Besides that, the statistical properties of kurtosis showed that uphill data were the highest at 3.81 resulted in the presence of high amplitude in the strain loading data. For fatigue life-based reliability assessment, the SWT model provided a narrower shape compared to the Coffin–Manson and Morrow models using the Gumbel distribution. The SWT model had the lowest mean cycle to failure of 1,250 cycle/block followed by Morrow model (1,317 cycle/block) and the Coffin–Manson model (1,429 cycle/block). The SWT model considers the mean stress effects by interpreting the strain energy density that will influence the reliability assessment.

The reliability assessment based on fatigue life prediction is conducted using the Gumbel distribution to investigate the behaviour of fatigue random loading, where most previous studies had concentrated on a Weibull distribution on random data.

Thus, this study proposes that the Gumbel distribution is suitable for analysing the reliability of random loading data in assessing with the fatigue life prediction of a heavy vehicle leaf spring.

Advanced computational methods help to solve complex engineering problems via finite-element simulation. However, uncertainties during the process occurred due to the nature of geometry, material properties, loading, and boundary conditions. These inaccuracies affect the accuracy of results obtained from the analysis. This paper aims to analyse the uncertainty parameters of a finite element model in Excel-Visual Basic Application (VBA) by applying a random simulation method.

This study focuses on a finite element model with a different mesh. Young's Modulus, E, Poisson's ratio, and load, L are the uncertainty input parameters considered random variables.

Results obtained proved that the finite element model with the most nodes and elements has better solution convergence.

Random simulation method is a tool to perform uncertainty analysis of a finite element model.

This paper aims to evaluate the validity of bilinear hardening model to represent the stress flow of high-pressure torsion (HPT)-strengthened lightweight material, AA2024.

Finite-element HPT simulation was performed by applying a simultaneous prescribed displacement on the axial and rotational axis that is equivalent to 4 GPa pressure and 30° torsion. The material behaviour incorporates plasticity attributes with a bilinear constitutive equation that consists of elastic and tangent modulus.

As a result, the von Mises stress generated from the simulation is in good agreement with the experiment, indicating that the assumptions of plasticity properties applied for the FEM simulation model are acceptable. The model verification confirms the anticipated plasticity parameters’ effect on the generated von Mises stress. The disc centre also evidenced an insignificant stress increment due to the limited shear straining.

A reliable hardening model would assist in understanding the stress flow associated with mechanical properties enhancement.

The bilinear hardening model exhibits a satisfactory stress estimation. It simplifies the ideal strain variable hardening procedures and lessens the total computation time that is valuable in solving severe plastic deformation problems.

An integration of well-defined input parameters, concerning the hardening behaviour and the plasticity properties, contributes to the establishment of a validated HPT simulation model, particularly for AA2024. This study also proved that perfectly plastic behaviour is inappropriate to represent hardening in the HPT-strengthened materials due to the remarkable stress deviation from the experimental data.

The purpose of this paper is to examine the plasticity behaviour of aluminium alloys in high-pressure torsion (HPT) compressive loading stage. It is a part of the strengthen lightweight material development through severe plastic deformation.

A finite element simulation of HPT compression stage by displacement control incremental loading was proposed by taking into account an unconstraint HPT configuration. The quasi-static condition was utilised, by embedding strain hardening plasticity constitutive model and considering frictional effects, to assess the plasticity behaviour of aluminium alloys, particularly AA2024 and AA6082.

The present investigation clearly indicates that the deviation of material flow as a result of sticking condition of µ⩾0.5, was found to be negligible. An inhomogeneous material flow along the sample radial and thickness direction was evident, producing a stress concentration at the edge of the loaded surface, indicating the anticipated region of failure. The effective plastic strain in the compression stage was also found to be significant. Based on the effective strain response, plasticity behaviour of the compressed sample was predicted.

This paper demonstrates the plasticity behaviour of the analysed aluminium alloys. Since the mechanical properties produced by the deformed material are closely related to the exerted plastic deformation, understanding the phenomenon associated with the plastic strain development is essential. The outcome of this research will assist in seizing the opportunities of improving both material properties and the HPT procedures.

The purpose of this paper is to establish a peridynamic method in predicting viscoelastic creep behaviour with recovery stage and to find the suitable numerical parameters of peridynamic method.

A rheological viscoelastic creep constitutive equation including recovery and an elastic peridynamic equation (with integral basis) are examined and used. The elasticity equation within the peridynamic equation is replaced by the viscoelastic equation. A new peridynamic method with two time parameters, i.e. numerical time and viscoelastic real time is designed. The two parameters of peridynamic method, horizon radius and number of nodes per unit volume are studied to get their optimal values. In validating this peridynamic method, comparisons are made between numerical and analytical result and between numerical and experimental data.

The new peridynamic method for viscoelastic creep behaviour is approved by the good matching in numerical-analytical data comparison with difference of < 0.1 per cent and in numerical-experimental data comparison with difference of 4-6 per cent. It can be used for further creep test which may include non-linear viscoelastic behaviour and creep rupture. From this paper, the variation of constants in Burger’s viscoelastic model is also studied and groups of constants values that can simulate solid, fluid and solid-fluid viscoelastic behaviours were obtained. In addition, the numerical peridynamic parameters were also manipulated and examined to achieve the optimal values of the parameters.

The peridynamic model of viscoelastic creep behaviour preferably should have only one time parameter. This can only be done by solving the unstable fluctuation of dynamic results, which is not discussed in this paper. Another limitation is the tertiary region and creep rupture are not included in this paper.

The viscoelastic peridynamic model in this paper can serve as an alternative for conventional numerical simulations in viscoelastic area. This model also is the initial step of developing peridynamic model of viscoelastic creep rupture properties (crack initiation, crack propagation, crack branching, etc.), where this future model has high potential in predicting failure behaviours of any components, tools or structures, and hence increase safety and reduce loss.

The application of viscoelastic creep constitutive model on peridynamic formulation, effect of peridynamic parameters manipulation on numerical result, and optimization of constants of viscoelastic model in simulating three types of viscoelastic creep behaviours.

Throughout the extant studies on Islamic work values, many variations in the concept of Islamic work values were found. This has created some confusions and misunderstandings on what is the core of Islamic work values that is highly emphasized by Islam. The unanimity of Islamic work values is fundamental to Islamic organizations, and businesses in particular, as it indicates ethical, effectiveness and religious reputations of the organizations. This paper aims to identify the core Islamic work values based on Islamic legal texts (the Qur‘an and the Hadith as the two main Islamic sources), the writings of Islamic scholars and then to have experts verify whether or not the identified work values are core Islamic work values.

The paper used a qualitative approach where Islamic legal texts (the Qur’an and the Hadith) as well as the writing of Islamic scholars were used as a main reference to identify the core Islamic work values. These identified core Islamic work values were later verified by the muftīs. The verification assessment involved six muftīs from Malaysia.

The final result revealed that 14 core Islamic work values have been verified by the muftīs. These 14 considered core Islamic work values are essential work values of Islam which are important to achieve effective work performance.

The findings presented are useful for managers and employees in Islamic organizations to decide on what Islamic work values that should be given more precedence and to be practised in their organizations.

This is a novel study that combines two approaches, the Islamic legal texts and muftīs verification regarding the work values obtained that can be accepted as the core Islamic work values. Therefore, these findings can be a guide for many future studies in the area of Islamic work values.

This study aims to investigate the factors influencing the adoption of online pharmacies in Qatar using the unified theory of acceptance and use of technology-2 (UTAUT-2) framework. Specifically, this study examines the impact of performance expectancy, effort expectancy, social influence, hedonic motivation, habit, technology trust, perceived risk and users’ level of awareness of behavioral intention, which in turn affects the adoption of online pharmacies. Furthermore, this study explores the moderating role of word-of-mouth (WOM) recommendations on the relationship between behavioral intention and online pharmacy adaptation.

This study adopted a descriptive, quantitative approach to investigate the UTAUT-2 model in the context of consumers’ adoption of e-pharmacy in Qatar. Through convenience sampling, 455 responses were collected from regular customers accessing online pharmacy services. The data were analyzed using Smart-PLS 3.2 software to examine the hypothesized relationships.

The results showed that WOM recommendations significantly enhanced the relationship between behavioral intention and adopting online pharmacies in Qatar. This study identified the factors that may hinder or enable the adoption of online pharmacies, including performance expectancy, effort expectancy, social influence, hedonic motivation, habit, technology trust, perceived risk and users’ level of awareness.

This study contributes to the existing literature on technology acceptance by extending the UTAUT-2 model and recognizing three additional variables (perceived risk, technology trust and technology awareness). These need to be investigated against UTAUT-2 variables to detect the significance of their impact on adapting the e-health concept in Qatar. The potential for cultural change to accelerate the adoption of online pharmacies is highlighted. Future research should explore the role of moral and cultural factors in technology adoption.

The results underscore the economic and social significance of e-pharmacy adoption, particularly within the context of a developing country. Considering the positive intentions expressed by individuals toward e-pharmacy, it becomes crucial for managers and decision-makers to make strategic choices to address any challenges that may arise. Policymakers are encouraged to enhance their services and implement various development initiatives to expand e-pharmacy accessibility and availability.

This study builds upon previous research on e-commerce in the pharmaceutical industry and provides a comprehensive understanding of customers in developing countries. Extending the UTAUT-2 model and identifying additional variables contributes to the knowledge of e-health concepts in Qatar. The findings have practical implications for developing strategies to promote online pharmacy adoption in Qatar and other countries.

The purpose of this paper is to test a conceptual model that takes into account both edu-tourists’ perception and perceived service quality in explaining purchase intention of academic degrees from the foreign universities.

The study is based on an empirical examination with applying multivariate data analysis. The data were collected through survey questionnaires and analysed by using structural equation modelling procedure.

The survey result discovered that the relationship between perceived service quality and edu-tourist’s satisfaction was significant and positive. The relationship between edu-tourist’s satisfaction and intention to purchase was also significant and positive. Meanwhile, edu-tourist’s satisfaction partially mediates the relationship between their perceived service quality and intention to purchase. Nevertheless, this research also explored that the edu-tourist’s satisfaction plays a significant mediating effect in between the relationship of perception and intention to purchase.

This empirical study will contribute in understanding the behaviour of international students to construct the theoretical knowledge on the edu-tourism industry, which has been neglected in tourism research.

The paper will be of use to the management and policymakers in the higher education sector in understanding the customer’s expectation for the edu-tourism destination. This study contributes to the growing literature on education travel destination, where the researchers investigated the role of tourist’s satisfaction by using perception and perceived service quality towards their intention to visit a destination for education tourism. In addition, understanding the role satisfaction on the relationship between perception and perceived service quality towards the purchase intention will make both scientific and practical contributions for the decision-makers.

The purpose of this study is to systematically examine and compare the growth of halal tourism and hospitality in OIC and non-OIC countries based on published literature.

A critical systematic review of 154 academic papers published in the last decade involving halal tourism in OIC and non-OIC countries constituted the sample for this study. The study uses an integrated antecedents, decisions and outcomes and theories, contexts and methods framework, and a coding protocol based on the preferred reporting items for systematic reviews and meta-analyses.

Halal tourism is not developed in non-OIC countries where Islam does not predominate, which represents an opportunity for many countries to incorporate new trends in their tourism offerings. This research increases awareness of non-OIC destinations to welcome a growing halal tourism market, enabling them to foster innovation to meet new demands for Muslim travelers.

This study is different as we compare the pertinent needs that are based on religion in various geographical locations while focusing on tourism and hospitality research in Islamic and non-Islamic nations.