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Rainfall is one of the main atmospheric conditions that significantly affect the aerodynamic performance of the low Reynolds number flights. In this paper, the adverse effects of rain on the aerodynamic performance of a two-dimensional (2D) airfoil with a chord-based low Reynolds number of 2 × 10⁵ and the mini-unmanned aerial vehicle (UAV) for various flight conditions, i.e. 0°–40° at Mach number 0.04 were studied numerically. The purpose of this study is to explore the aerodynamic penalties that affect the liquid water content (LWC = 5.33) of the airfoil and UAV performance in rain under different flying conditions.

The Eulerian–Lagrangian two-phase flow method is adopted to simulate the rain environment over an airfoil and mini-UAV aerodynamic performances. The Reynolds Averaged Navier–Stokes equations are considered to solve the time-averaged equations of motion for fluid flow.

The effect of rainfall on the airfoil and mini-UAV is studied numerically and validated experimentally. For 2D airfoil, the lift and drag coefficients for both numerical and experimental results show a very good correlation at Reynolds number 2 × 10⁵. For three-dimensional (3D) mini-UAV, the lift and drag coefficients for both numerical and experimental results show a very good correlation at Mach number 0.04. The raindrops distribution around the airfoil, premature trailing edge separation, boundary-layer velocity profiles at five different chord positions (i.e. LE, 0.25c, 0.5c, 0.75c and 0.98c) on the upper surface of the airfoil, water film height and the location of rivulet formation on the upper surface of the airfoil are also presented.

For 2D airfoil, the recorded maximum variation of the coefficient of lift and lift-to-drag (L/D) ratio is observed to be 5.33% at an 8° and 10.53% at a 4° angle of attack (AOA) between numerical and experimental results under the influence of rainfall effect for LWC = 5.33. The L/D ratio percentage degradation is seen to be 61.9% at an AOA of 0°–2° for the rain environment. For 3D mini-UAV, the recorded maximum variation of the coefficient of lift and L/D ratio are observed to be 2.84% and 4.60% at a 30° stall AOA under the influence of rainfall effect for LWC = 5.33. The numerical results are impressively in agreement with the experimental results. UAV designers will benefit from the findings presented in this paper. This will be also helpful for training the pilots to control the airplanes in a rain environment.

University academicians are struggling to engage in teaching, supervision, research and publication. The purpose of this paper is to determine how academicians cope with the various burdens of academia work stressors to overcome burnout.

A cross-sectional study was conducted from January to July 2017. In total, 327 research university academicians were selected using a proportional stratified randomized sampling. Validated measures were used to collect data on perceived work stressors (teaching, research, interpersonal conflicts and career development), coping strategies (adaptive and maladaptive coping) and perceived burnout (emotional exhaustion (EE), depersonalization and personal accomplishment (PA)). The data were gathered via computer assisted self-interviewing (CASI). The research statistical model was tested by two-steps of assessment replicating covariance-based structural equation modeling (CB-SEM) with bootstrapping procedure to generalize the sample to the hypothesized model.

Overall data fit the hypothesized model well (CMIN/df=1.788, GFI=0.833, CFI=0.921, TLI=0.916, RMSEA=0.047) with various degree of explanatory value for EE, depersonalization and PA were 60, 49 and 22 percent, respectively. Academicians were resilient against the burden of teaching. However, they did adopt coping mechanisms to overcome research challenges and interpersonal conflicts. The effects of research and interpersonal conflicts on tri-dimensional burnout mediated by maladaptive coping (f² effect size=0.37) had a larger effect than interpersonal conflicts toward burnout mediated by adaptive coping (f² effect size=0.02).

Academicians adopt maladaptive coping for research and interpersonal conflicts to suppress burnout. An integrative approach at both organization and individual levels is crucial to enhance appropriate coping mechanism to curb with burnout among the academicians of a research university.

This is the first study in Malaysia which uniquely estimate the effects of academician’s work stressors toward burnout with introducing coping strategies as mediators toward work stressors and burnout relationship which has been analyzed via CB-SEM.

The purpose of this paper is to develop an empirical equation of SRB corrosion based on their metabolic species.

Solution containing SRB metabolic species was simulated using abiotic chemistry approach. Linear polarization technique was used to measure the corrosion rate of X52‐sample in simulated solution containing SRB metabolic products species. The curve obtained from LPR data was then fitted using multiple non‐linear regression method by Minitab 15^® software.

Statistical analysis shows that sulphide and sulphite have significant effect on the X52 corrosion rate.

Using abiotic chemistry approach, an empirical equation that considers SRB metabolic species has been developed. The equation could be used to predict carbon steel corrosion rate by SRB.

This work aims to study the hydrothermal behavior of mortar cement toward certain environmental factors (ambient air temperature and air velocity) based on its drying kinetics data. The objective is to provide a better understanding and controlling the stability of mortar structures, which integrate the sorption phenomenon, drying process, air pressure and intrinsic characteristics. This leads to predict the comportment of mortar structures in relation with main environmental factors and minimize the risk of cracking mortar structures at an early age.

Thermokinetic study was carried out in natural and forced convection solar drying at three temperatures 20, 30 and 40°C and three air velocities (1, 3 and 5 m.s-¹). The empirical and semiempirical models tested successfully describe the drying kinetics of mortar. These models simulate the drying process of water absorbed by capillarity, which is the most common humidity transfer mechanism in building materials and contain parameters with physical significance, which integrate the effect of several environmental factors and intrinsic characteristics of mortar structures.

The models simulate the drying process of water absorbed by capillarity, which is the most common humidity transfer mechanism in building materials and contain parameters with physical significance, which integrate the effect of several environmental factors and intrinsic characteristics of mortar structures. The average activation energy obtained expressed the temperature effect on the mortar diffusivity. The drying constant and the diffusion coefficient can be used to predict the influence of these environmental factors on the drying behavior of various building materials and therefore on their durability.

Evaluation of the effect of several environmental factors and intrinsic characteristics of mortar structures on their durability.

This study aims to identify the terminology that is in accordance with the reality of Muslim tourism market, especially from the perspective of Sharia motivation, between Halal tourism and Islamic tourism; provide information on the special needs of Muslim travelers based on the dominant motivational differences; and find the impact of Sharia motivation and the special needs of Muslim tourists to their satisfaction.

The target population in this study is Muslim traveler at least 18 years old who has been traveling throughout Indonesia. Paired sample t-Test, multivariate analysis of variance and the multiple linier regression are applied for data analysis.

This study finds that Sharia motivation is less dominant in encouraging Muslims to travel; Sharia motivation has no impact on the importance of Sharia transportation, generic transportation and generic activities; and the dominance of Sharia motivation does not affect Muslim tourist satisfaction. However, the dominance of Sharia motivation has an influence on the importance of Sharia accommodation and Sharia activities, where both variables have positive effect on satisfaction. In the end, this study concludes that it is better to use the concept of Halal tourism than Islamic tourism.

This paper investigates the term of Halal tourism and Islamic tourism that are still ambiguous; even some researchers consider that the definition of both is similar.

This chapter investigated tendering in stealth construction, emphasising innovative approaches and methodologies that prioritise environmental protection, safety, efficiency, and aesthetics. It began with an overview of the construction industry’s tendering processes, followed by an in-depth examination of various tendering types, including competitive and negotiated methods. The study highlighted contemporary trends such as electronic tendering, Building Information Modelling (BIM), green and sustainable procurement, risk management, data analytics, artificial intelligence, lean construction practices, and blockchain technology. Moreover, with a specific focus on stealth construction, the chapter further analysed certain criteria, including building cross-section development, visibility, radio frequency emission, and countermeasures. It explored integrating functional construction systems, including environmental, safety, health, and quality management. Additionally, it discussed methods like green building, modular construction, and low-impact techniques. Lastly, the chapter emphasised the strategies to achieve environmental protection, safety, speed, economy, and aesthetics in tendering for stealth construction.

The construction business is widely recognised for its inherent complexity and dynamic nature, which stems from the nature of the job involved. The industry is often regarded as one of the most challenging industries globally in terms of implementing environmental, health and safety (EHS) practices. However, in the absence of EHS, the construction industry cannot be considered sustainable. Therefore, this study aims to identify the trends, knowledge gaps and implications of EHS research to enhance construction activities and knowledge.

The study adopted a science mapping approach involving bibliometric and scientometric analysis of 407 construction EHS publications from the Scopus database with the VOSviewer software. The study is based on journal articles from the Scopus database without restriction to any time range.

The main focus of construction EHS research identified in the study includes sustainability-related studies, risk-related, environmental issues, EHS management, integrated management systems studies, health and safety related and EHS in the construction process. Some emerging areas also identified include productivity, design, culture, social sustainability and machine learning. The most influential and productive publication sources, countries/regions and EHS publications with the highest impact were also determined.

Documents published in the Scopus database were considered for analysis because of the wider coverage of the database. Journal articles written in English language represent the inclusion criteria, whereas other documents were excluded from the analysis. The study also limited the search to articles with the engineering subject area.

The research findings will enlighten stakeholders and practitioners on the focal knowledge areas in the EHS research domain, which are vital for enhancing EHS in the industry.

To the best of the authors’ knowledge, this review-based study is the first attempt to internationally conduct a science mapping on extant literature in the EHS research domain through bibliometric and scientometric assessments.

This paper asserts that sustainable tourism education is an issue of extreme importance, especially for young adolescents, ages 10 to 12. Despite little intersection between middle-school education and tourism education, these two fields can become natural allies. Today's preteens not only influence their parent's tourism choices but will shape tomorrow's tourism, both as tourists and as hosts. This study is addressing the following research questions: if transformational school trips with tourism sustainability education proposes improve or enhance students' confidence and initiative, and how middle school individuals can become familiar with responsible and sustainable tourism and act upon it. Thus, the conceptual framework offered in this article is intended to contribute to a more systematic, programmatic, theory-based approach to the study of education for sustainable tourism in middle schools, and that by empowering students through travel. Results suggest that empowering middle-school individuals is halfway to achieve tourism sustainability goals.

Purpose: This study aims to explore the efforts of several Asian countries adopting blockchain-enabled letter of credit (LC) processes and highlight the key challenges hindering blockchain adoption into the entire LC system.

Need for the study: As trade volume among countries grows, nations should agree on the technology’s application mechanism to prevent disputes over discrete practices. As blockchain is a borderless approach, the global context of the applications should be considered, incorporating the cases of Asia, the hub of intraregional collaboration in trading.

Methodology: This chapter has surveyed the existing literature to identify the dichotomy between blockchain-enabled LC and traditional LC. Ten Asian countries were selected considering their adaptation motivations, number of use cases, and economic outlook. The case-study method was applied to compare the counties.

Findings: Countries reported blockchain-enabled LC as time-efficient, less costly, and secure. Interoperability, scalability, the absence of legal and administrative infrastructure, stress for new skills, and cyber security concerns are the most cited challenges among users. Instances of regulatory sandbox and collaborative effort were found among some countries, although some countries have yet to publish application guidelines.

Practical implication: The study provides comparative pictures of blockchain-enabled LC systems adopted by several Asian countries. This will contribute to future collaboration between Asian countries to create a unified and standardised trade financing platform. The study will also contribute to the future formulation of guidelines for administrative methodologies of the permissioned blockchain application in the trade finance section.

This study aims to examine the relationship of work–family demands with employees’ well-being, and the role of management/supervisory support in this relationship. The following hypotheses were proposed: work–family demands would be negatively related to employees’ well-being; management/supervisory support would moderate the relationship of work–family demands with employees’ well-being.

The researchers used 250 working female academicians as respondents, working in the research universities in Kuala Lumpur, Malaysia. Their ages ranged from 30 to 60 years.

The findings of the present study proved that the work–family demands were negatively associated with employees’ well-being. Results also revealed that management and supervisory support strengthens the relationship between work–family demands and employees’ well-being. Thus, management and supervisory support plays an important role in balancing work demands and family roles and also in increasing working female academicians’ well-being.

In this study, management and supervisory support was found to be directly related to well-being, including life satisfaction, job satisfaction and family satisfaction. However, the direct relationship between management/supervisory support and well-being was positive and significant. This study also found that management/supervisor support reduced work–family conflict and work–family demands. Also, supervisory and management support was found to have a significant and positive relationship with well-being. Given these findings, supervisory and management support plays a very important role as a moderator of work–family demands and in developing and improving well-being in working women.