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The purpose of this paper is to present a three-dimensional finite volume-based analysis on the effects of propeller blades on fountain flow in a wave soldering process and performs an experimental validation.

Solder pot models with various numbers of propeller blades were developed and meshed by using hybrid elements and simulated by using the FLUENT fluid flow solver. The characteristics of the fountain, such as flow profile, velocity vector, filling time, and fountain advancement, were investigated. Molten solder (Sn63Pb37) material, a temperature of 250°C, and a propeller speed of 830 rpm were applied in the simulation. The predicted results were validated by the experimental fountain profile.

The use of a six-blade propeller in a solder pot increased the fountain thickness profile and reduced the filling time. Moreover, a six-blade propeller design resulted in a stable fountain profile and was considered the best choice for current wave soldering processes.

This study provides a better understanding of the effects of propeller blades on the fountain flow in the wave soldering process.

The study explores the fountain flow behavior and provides a reference to the engineers and designers in order to improve the fountain flow of the wave soldering.

This study examines the interactive effects of work values and organisational commitment on localisation.

This study draws on human capital theory, and reports on a survey of 200 expatriate managers working in Qatar.

We find that localisation is negatively associated with work values and positively associated with organisational commitment. Furthermore, work values appear to influence organisational commitment.

Despite a surfeit of literature on localisation of human resources, few studies previously have explored its relationship with work values and organisational commitment. This chapter presents empirical research on the issue from Qatar, a country in a region which remains under-researched in the literature.

The purpose of this strengths or weaknesses, and its external opportunities or threats (SWOT) analysis study on Halal logistics industry in Malaysia is to identify SWOT in the Halal logistics environment and to uncover strategies to leverage on the strengths and opportunities and rectifying the weaknesses as well as overcoming the threats.

This study comprises two methods: literature review and interviews. Extensive literature reviews were obtained from leading databases and the articles recorded matches or related with the keywords. In addition, the respondents from the interviews consist of middle- and top-level managers with reputable knowledge, expertise and experience in the Logistics and Halal industry. After the literature was reviewed and information was transcribed from the interviews, reduction techniques were used to group and summarize the variables into the four SWOT categories.

The SWOT categories, consisting of SWOT, are generated from the literature reviews and supported by the respondents’ views and vice versa. Examples of SWOT analyses done are as follows: strength (strong government support), weakness (inconsistent Halal definition), opportunity (Muslims’ population growth) and threat (no uniformity on Halal standards).

The SWOT analysis done for this study only demonstrates the internal and external environments and not the assumption that they are certain to be correct, as they contain every imaginable matter in relation to Halal logistics. Plus, the analysis done does not show how to achieve competitive advantage, merely as a guideline and the SWOT analysis done may be outdated as the environments are constantly changing.

The study hopes to contribute in future studies and act as a guide for the Halal logistics players to have better understanding in their business environment.

This study is the first of its kind, to incorporate SWOT and Halal logistics. Hence, this study will add in more value to the existing academic research done on SWOT analysis and broadening the Halal and logistics business understanding, not only in Malaysia but globally as well.

Each place possesses characteristics that confer on it a sense of place and identity through the meanings and values that they provide. The role of the physical built environment in place and identity development has not received adequate attention in built environment literature. This paper attempts to identify the unique and exceptional characteristics of places which create a unique environment and make a continuing contribution to the overall sense of the place. A preliminary survey was conducted in Kuala Kubu Bharu (KKB), a small town in the northern part of the Malaysian state of Selangor; to examine the characteristics of the place that influence and contribute to the identity of the town. The survey results demonstrate that the cultural heritage of the physical built environment acts as an important trigger for the town’s identity. While it is undeniable that cultural heritage is indeed greatly the product of non-visual sources; subjective meanings, experiences, beliefs, ideology and past history of the place, this paper highlights the significance of the physical built environment in influencing the very individuality of the place.

The purpose of this paper is to examine the effects of heat capacity and density of biofuels on aircraft engine performance indicated by thrust and fuel consumption.

The influence of heat capacity and density was examined by simulating biofuels in a two-spool high-bypass turbofan engine running at cruise condition using a Cranfield in-house engine performance computer tool (PYTHIA). The effect of heat capacity and density on engine performance was evaluated through a comparison between kerosene and biofuels. Two types of biofuels were considered: Jatropha Bio-synthetic Paraffinic Kerosene (JSPK) and Camelina Bio-synthetic Paraffinic Kerosene (CSPK).

Results show an increase in engine thrust and a reduction in fuel consumption as the percentage of biofuel in the kerosene/biofuel mixture increases. Besides a low heating value, an effect of heat capacity on increasing engine thrust and an effect of density on reducing engine fuel consumption are observed.

The utilisation of biofuel in aircraft engines may result in reducing over-dependency on crude oil.

This paper observes secondary factors (heat capacity and density) that may influence aircraft engine performance which should be taken into consideration when selecting new fuel for new engine designs.

The purpose of this paper is to investigate the mechanisms of frictional wear stability of an activated carbon composite derived from palm kernel using phase transformation study.

The unlubricated sliding test was executed using a ball-on-disc tribometer at different loads with a constant speed, sliding distance and temperature.

Results of this paper suggest that stability of friction and wear of the test materials are primarily due to the phase transformation of the composite surface layer.

However, the effectiveness of the transfer layer as a medium for low friction and wear is only limited at certain applied loads.

This is the first study, to the authors’ knowledge, to find out the mechanisms of low frictional wear properties of an activated carbon composite derived from palm kernel using phase transformation study.

The purpose of this paper was to investigate the lubricity of palm biodiesel (PB)–diesel fuel with plastic pyrolysis oil (PPO) and waste cooking biodiesel (WCB).

Three quaternary fuels were prepared by mechanical stirring. B10 (10% PB in diesel) fuel was blended with 5%, 10% and 15% of both PPO and WCB. The results were compared to B30 (30% PB in diesel) and B10. The lubricity of fuel samples was determined using high-frequency reciprocating rig in accordance with ASTM D6079. The tribological behavior of all fuels was assessed by using scanning electron microscopy on worn steel plates to determine wear scar diameter (WSD) and surface morphology. The reported WSD is the average of the major and minor axis of the wear scar.

The addition of PPO and WCB to B10 had improved its lubricity while lowering wear and friction coefficients. Among the quaternary fuels, B40 showed the greatest reduction in coefficient of friction and WSD, with 7.63% and 44.5%, respectively, when compared to B10. When compared to B30a, the quaternary fuel mixes (B40, B30b and B20) exhibited significant reduction in WSD by 49.66%, 42.84% and 40.24%, respectively. Among the quaternary fuels, B40 exhibited the best overall lubricating performance, which was supported by surface morphology analysis. The evaluation of B40 indicated a reduced adhesive wear and tribo-oxidation, as well as a smoother metal surface, as compared to B20 and B30b.

Incorporation of PPO and WCB in PB–diesel blend as a quaternary fuel blend in diesel engines has not been reported. Only a few researchers looked into the impact of PPO and WCB on the lubricity of the fuel.

This paper aims to investigate the thermal fluid–structure interactions (FSIs) of printed circuit boards (PCBs) at different component configurations during the wave soldering process and experimental validation.

The thermally induced displacement and stress on the PCB and its components are the foci of this study. Finite volume solver FLUENT and finite element solver ABAQUS, coupled with a mesh-based parallel code coupling interface, were utilized to perform the analysis. A sound card PCB (138 × 85 × 1.5 mm3), consisting of a transistor, diode, capacitor, connector and integrated circuit package, was built and meshed by using computational fluid dynamics pre-processing software. The volume of fluid technique with the second-order upwind scheme was applied to track the molten solder. C language was utilized to write the user-defined functions of the thermal profile. The structural solver analyzed the temperature distribution, displacement and stress of the PCB and its components. The predicted temperature was validated by the experimental results.

Different PCB component configurations resulted in different temperature distributions, thermally induced stresses and displacements to the PCB and its components. Results show that PCB component configurations significantly influence the PCB and yield unfavorable deformation and stress.

This study provides PCB designers with a profound understanding of the thermal FSI phenomenon of the process control during wave soldering in the microelectronics industry.

This study provides useful guidelines and references by extending the understanding on the thermal FSI behavior of molten solder for PCBs. This study also explores the behaviors and influences of PCB components at different configurations during the wave soldering process.

Computational fluid dynamics (CFD) simulation of the flow field around marine propellers is challenging because of geometric complexity and rotational effects. To capture the flow structure, grid quality and distribution around the blades is primordial. This paper aims to demonstrate that solution-based automatic mesh optimization is the most logical and practical way to achieve optimal CFD solutions.

In the current paper, open water propeller performance coefficients such as thrust and torque coefficients are numerically investigated. An anisotropic mesh adaptation technique is applied, believed for the first time, to marine propellers and to two computational domains.

The current study’s performance coefficients are compared with other previously published CFD results and improvements in terms of accuracy and computational cost are vividly demonstrated for different advance coefficients, as well as a much sharper capture of the complex flow features.

It will be clearly demonstrated that these two improvements can be achieved, surprisingly, at a much lower meshing and computational cost.

This study aims to determine the minimum force required to pull out a surface mount component in printed circuit boards (PCBs) during the wave soldering process through both experimental and numerical procedures.

An efficient experimental technique was proposed to determine the minimum force required to pull out a surface mount component in PCBs during the wave soldering process.

The results showed that the pullout force is approximately 0.4 N. Comparing this value with the simulated force exerted by the solder wave on the component ( ≅ 0.001158 N), it can be concluded that the solder wave does not exert sufficient force to remove a component.

This study provides a deep understanding of the wave soldering process regarding the component pullout, a critical issue that usually occurs in the microelectronics industry during this soldering process. By applying both accurate experimental and numerical approaches, this study showed that more tests are needed to evaluate the main cause of this problem, as well as new insights were provided into the depositing process of glue dots on PCBs.