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This study aims to investigate the effects of propeller locations on the aerodynamic characteristics of a generic 55° swept angle sharp-edged delta wing unmanned aerial vehicle (UAV) model.

A generic delta-winged UAV model has been designed and fabricated to investigate the aerodynamic properties of the model when the propeller is placed at three different locations. In this research, the propeller has been placed at three different positions on the wing, namely, front, middle and rear. The experiments were conducted in a closed-circuit low-speed wind tunnel at speeds of 20 and 25 m/s corresponding to 0.6 × 10⁶ and 0.8 × 10⁶ Reynolds numbers, respectively. The propeller speed was set at constant 6,000 RPM and the angles of attack were varied from 0° to 20° for all cases. During the experiment, two measurement techniques were used on the wing, which were the steady balance measurement and surface pressure measurement.

The results show that the locations of the propeller have significant influence on the lift, drag and pitching moment of the UAV. Another important observation obtained from this study is that the location of the propeller can affect the development of the vortex and vortex breakdown. The results also show that the propeller advance ratio can also influence the characteristics of the primary vortex developed on the wing. Another main observation was that the size of the primary vortex decreases if the propeller advance ratio is increased.

There are various forms of UAVs, one of them is in the delta-shaped planform. The data obtained from this experiment can be used to understand the aerodynamic properties and best propeller locations for the similar UAV aircrafts.

To the best of the author’s knowledge, the surface pressure data available for a non-slender delta-shaped UAV model is limited. The data presented in this paper would provide a better insight into the flow characteristics of generic delta winged UAV at three different propeller locations.

This study aims to investigate the micropolar fluid flow through a moving flat plate containing CoFe₂O₄-TiO₂ hybrid nanoparticles with the substantial influence of thermophoresis particle deposition and viscous dissipation.

The partial differential equations are converted to the similarity equations of a particular form through the similarity variables. Numerical outcomes are computed by applying the built-in program bvp4c in MATLAB. The process of flow, heat and mass transfers phenomena are examined for several physical aspects such as the hybrid nanoparticles, micropolar parameter, the thermophoresis particle deposition and the viscous dissipation.

The friction factor, heat and mass transfer rates are higher with an increment of 1.4%, 2.2% and 1.4%, respectively, in the presence of the hybrid nanoparticles (with 2% volume fraction). However, they are declined because of the rise of the micropolar parameter. The imposition of viscous dissipation reduces the heat transfer rate, significantly. Meanwhile, thermophoresis particle deposition boosts the mass transfer. Multiple solutions are developed for a certain range of physical parameters. Lastly, the first solution is shown to be stable and reliable physically.

As far as the authors have concerned, no work on thermophoresis particle deposition of hybrid nanoparticles on micropolar flow through a moving flat plate with viscous dissipation effect has been reported in the literature. Most importantly, this current study reported the stability analysis of the non-unique solutions and, therefore, fills the gap of the study and contributes to new outcomes in this particular problem.

This study aims to investigate the flow impinging on a stagnation point of a shrinking cylinder subjected to prescribed surface heat flux in Al₂O₃-Cu/water hybrid nanofluid.

Using similarity variables, the similarity equations are obtained and then solved using bvp4c in MATLAB. The effects of several physical parameters on the skin friction and heat transfer rate, as well as the velocity and temperature profiles are analysed and discussed.

The outcomes show that dual solutions are possible for the shrinking case, in the range λc<λ<−1, where λc is the bifurcation point of the solutions. Meanwhile, the solution is unique for λ≥−1. Besides, the boundary layer is detached on the surface at λc, where the value of λc is affected by the hybrid nanoparticle φhnf and the curvature parameter γ. Moreover, the friction and the heat transfer on the surface increase with the rising values φhnf and γ. Finally, the temporal stability analysis shows that the first solution is stable in the long run, whereas the second solution is not.

The present work considers the problem of stagnation point flow impinging on a shrinking cylinder containing Al₂O₃-Cu/water hybrid nanofluid, with prescribed surface heat flux. This paper shows that two solutions are obtained for the shrinking case. Further analysis shows that only one of the solutions is stable as time evolves.

This study aims to explore the stagnation flow over a shrinking surface in a hybrid nanofluid consists of Al₂O₃ and Cu nanoparticles. Here, the flow is subjected to the magnetohydrodynamic (MHD) and the melting phenomenon effects.

The similarity variables are used to gain the similarity equations. These equations are solved via the bvp4c solver. The effects of several physical parameters on the flow and the thermal characteristics of the hybrid nanofluid are analysed and discussed. Later, the temporal stability analysis is used to determine the stability of the dual solutions obtained as time evolves.

Results show that two solutions are found for the limited range of the stretching/shrinking parameter λ, and then these solutions are terminated at λ=λc. The rise of the melting parameter Me from 0 to 2 contributes to enhance 109.63% of the local Nusselt number Rex-1/2Nux and 3.30% of the skin friction coefficient Rex1/2Cf. Contrarily, the values of Rex-1/2Nux and Rex1/2Cf decline by 25.04% and 5.58%, respectively, as the magnetic parameter Mg increases from 0 to 0.3. Additionally, Al₂O₃-Cu/water has the highest values of Rex1/2Cf and the lowest values of Rex-1/2Nux. Lastly, it is found that the first solution is physically stable as time evolves.

This paper considers the MHD stagnation point flow of a hybrid nanofluid over a shrinking surface with the melting phenomenon effects. Most importantly, it is shown that there exist dual solutions within a specific range of the physical parameters. Besides, the temporal stability of the solutions is also reported in this study. The finding can contribute to foresee the flow and thermal behaviours in industrial applications. Also, the suitable values of parameters can be determined to avoid misjudgement in flow and heat transfer analysis.

There are rising issues with the delivery performance of Malaysian low-cost housing (LCH) because the occupants are inclined to perceive safety hazards. Among the safety issues raised during the occupancy period in LCH are structural instability and falling building fragments. Without defining the occupants’ requirements in the early housing development, it is hard to determine the prevailing safety factors. Hence, this paper emphasises the application of post occupancy evaluation (POE) that incorporates participation from the occupants as a tool to assess the safety performance of Malaysian LCH. The purpose of this study is to develop a framework of POE integrated with safety elements for Malaysian LCH.

This research was carried out with a quantitative method using questionnaires as the survey instrument involving safety inspection survey and satisfaction surveys. The inspection survey and Occupants’ Satisfaction Survey were carried out based on 24 LCH projects located in the federal territory of Kuala Lumpur, Malaysia. In total, 380 samples were used for both surveys. Statistical correlation was used to affirm the incorporation of occupants’ participation towards safety performance in the POE approach. The Spearman’s rho (r) correlation was used in the analysis for variables in both surveys which consisted of an ordinal scale.

The correlation result revealed that there was a significant relationship among all safety attributes between safety performance and occupants’ satisfaction. Therefore, a framework consisting of POE and safety elements has been proposed based on the significance of both variables. The development process of the framework used the vital phases of POE and inputs of safety elements which consisted of three main stages: planning phase as safety input, conducting phase as safety process and applying phase as safety output.

The surveys were limited to the rented People’s Housing Programme located in Kuala Lumpur and not extensively to all LCH programmes in Malaysia. The surveys were also not carried out to other LCH programmes such as the Hardcore Poor Housing Programmes and the low- to medium-cost housing because of the limitations of time and resources.

This research has introduced a new dimension for safety performance assessment in LCH using the POE as the safety performance tool. By allowing the participation of occupants for safety assessment, this study stresses the fundamental concept of POE by highlighting the importance of obtaining feedback from the building occupants.

As a proactive measure, the proposed framework was introduced as an improved procedure to inspect safety performance in LCH during occupancy, in lieu of the current assessment process. Receiving complaints from the occupants after the occurrence of incidents is demarcated as a reactive approach, whereas the current inspection survey does not incorporate the occupants’ participation. Feedback from occupants is not a routine of building assessment during occupancy; hence, using POE is generally a new dimension of safety performance in Malaysian LCH.

Effective building maintenance management is vital for reducing the impact of building defects and costly building maintenance work. Such practice significantly contributes to the public sector in terms of cost reduction, improved effectiveness and efficiency in maintenance works, increasing safety and well-being of the occupants, expanding the life of building stocks and expanding the value of investment for the government building assets. The maintenance practice in Malaysia is still emerging in comparison to many developed nations. The purpose of this study is to determine the current scenario of the building maintenance approach at the design stage in public buildings in Malaysia.

An extensive questionnaire survey was held, involving 312 key players (38 per cent out of 820 predetermined participants) in Malaysia.

The analysis showed that building maintenance in public building in Malaysia still uses the reactive approach. Despite the Malaysian Government’s adoption of a proactive maintenance approach, unfortunately, there are some misunderstandings among the key players regarding the approach. The research results demonstrate that the key players had a lack of understanding on the concept of the proactive maintenance management approach and that they were either ignorant or had insufficient awareness of proactive maintenance approach.

The contribution of this study is useful for the government to adopt a more proactive building maintenance policy at the design stage, to give awareness on proactive building maintenance to the key players in their construction project and as a guide to the key players to adopt a maintenance plan at the design stage of work.

This paper aims to accentuate the behavior of second-grade hybrid Al₂O₃–Cu nanofluid flow and its thermal characteristics driven by a stretching/shrinking Riga plate.

The second-grade fluid is considered with the combination of Cu and Al₂O₃ nanoparticles. Three base fluids namely water, ethylene glycol (EG) and methanol with different Prandtl number are also examined. The formulation of the mathematical model of second-grade hybrid nanofluid complies with the boundary layer approximations. The complexity of the governing model is reduced into a simpler differential equations using the similarity transformation. The bvp4c solver is fully used to solve the reduced equations. The observation of multiple solutions is conducted for the assisting (stretching) and opposing (shrinking) cases.

The impact of suction parameter, second-grade parameter, electromagnetohydrodynamics (EMHD) parameter, velocity ratio parameter and the volumetric concentration of the alumina and copper nanoparticles are numerically analyzed on the velocity and temperature profiles, skin friction coefficient and local Nusselt number (thermal rate) of the second-grade Al₂O₃–Cu/water. The solution is unique when (static and stretching cases) while dual for a specific range of negative in the presence of suction effect. Based on the appearance of the first solution in all cases of, it is physically showed that the first solution is stable. Further examination reveals that the EMHD and suction parameters are the contributing factors for the thermal enhancement of this non-Newtonian working fluid. Meanwhile, the viscosity of the non-Newtonian fluid also plays a significant role in the fluid motion and heat transfer rate based on the finding that the EG base fluid produces the maximum heat transfer rate but the lowest critical value and skin friction coefficient.

The results are novel and contribute to the discovery of the hybrid nanoparticles’ performance in the non-Newtonian second-grade fluid. Besides, this study is beneficial to the researchers in this field and general audience from industries regarding the factors, which contributing to the thermal enhancement of the working fluid.

It is widely evident that trust and commitment are important pillars for strengthening the relationship between financial service firms and their customers. However, it has not been explored how the service quality, perceived cost and role of agents are important for financial service firms. To overcome this gap, this study aims to investigate the role of service quality, perceived cost and the role of agents as the commitment–trust factors in the financial insurance service (Takaful) in Malaysia, enhancing customer satisfaction.

The study follows a quantitative design in which primary data was collected using a survey instrument. The measurement instrument was adapted from the previous research, and data were collected from 264 customers of the Takaful financial service organizations in Malaysia. The data were analyzed using variance-based structural equational modeling in Smart-PLS software.

This research has revealed several useful insights that demonstrate a significant impact on service quality, perceived cost and the agents’ role in forging close relationships with their customers. Corporate image has a moderating role in relationships and has significantly impacted takaful insurance companies. The results imply that regardless of the corporate image of the financial service organizations, customers are concerned about the prices and the quality of the agents’ services.

In this study, only the predictors such as service quality, perceived costs and agents’ roles as trust–commitment factors were examined to determine customer satisfaction. Other investigations are highly recommended, such as value co-creation in takaful, takaful customer experience and takaful trust. This study offers insights to takaful insurance companies on how to keep up a positive corporate image, which will boost their trust–commitment factors and ultimately increase customer satisfaction.

By presenting commitment–trust factors and company image in an identifiable framework, the current study has expanded the discussion on takaful financial insurance services. The methodology is developed and rigorously tested to gauge customer satisfaction in takaful financial service organizations’ context.

Creativity is the core of digital knowledge-based economic growth and competitiveness. Given the fact that public service is a major contributor to the country's governance system, creativity among civil servants should be enhanced. Effective leadership in public services is necessary to nurture the creativity of high-quality public services. This study aims to examine the effects of transformational leadership on civil servant's creativity.

This study was conducted in six selected public service agencies. A total of 214 questionnaires were distributed to civil servant offices, only 82.2 percent (176 questionnaires) were returned. Data were tested using SMART PLS to determine whether the four transformational leadership dimensions, namely, intellectual stimulation, idealized influence, individual consideration, and inspirational motivation, exhibit a significant effect on creativity of civil servant officers.

Findings showed positive effects of the four transformational leadership dimensions on the civil servant's creativity.

With small sample size, this study can still be expanded to all available public services sector in urban and rural area to gain a wider perspective.

This study presents strong managerial implications that can be used by public service to evaluate the consequence of transformational leadership on the creativity of employees, particularly the young civil servants. Through transformational leadership style, public service leaders can foster and improve young civil servants' creativity and share knowledge to achieve high performance.

With genuine verified measurement of transformative leadership and public sector creativity, the path correlation analysis shows that intellectual stimulation, idealized influence, individual consideration, and inspirational motivation have significant direct effects on creativity of the civil servant.

This paper aims to examine the effect of setting up a separate risk management committee (RMC) on the performance of listed companies in Malaysia's consumer goods sector. The study considers several firm characteristics as control variables to influence the establishment of the RMC, such as firm size and leverage.

The sample comprises 169 observations throughout a nine-year time frame starting from 2010 to 2018. The current study used a dichotomous variable of “1” to represent a listed company that establishes a separate RMC and “0” as otherwise. The data analysis is based on a static panel data technique, which utilised the fixed effects model (FEM) and random effects model (REM).

There is a significant positive relationship between a separate RMC and Tobin's Q which suggests that the establishment of a separate RMC that consists of a majority of independent non-executive directors would significantly improve the firm's performance. The current work supports agency theory which suggests that independent non-executive directors can enhance the transparency of corporate boards as they improved the firm's compliance with the disclosure requirements.

Proper risk management and internal control are critical aspects of a company's governance, management and operations that can influence a firm's performance. The empirical evidence contributes to the knowledge of corporate governance within the context of a RMC’s role in monitoring a company's risk management framework, policies and its implementation. The formation of a separate RMC as a board committee will help to enhance the effectiveness of the risk oversight role of the BOD.