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This study aims to investigate the interaction of independent variables [Reynolds number (Re), thermal power and the number of ball grid array (BGA) packages] and the relation of the variables with the responses [Nusselt number ((Nu) ¯ ), deflection/FPCB’s length (d/L) and von Mises stress]. The airflow and thermal effects were considered for optimizing the Re of various numbers of BGA packages with thermal power attached on flexible printed circuit board (FPCB) for optimum cooling performance with least deflection and stress by using the response surface method (RSM).

Flow and thermal effects on FPCB with heat source generated in the BGA packages have been examined in the simulation. The interactive relationship between factors (i.e. Re, thermal power and number of BGA packages) and responses (i.e. deflection over FPCB length ratio, stress and average Nusselt number) were analysed using analysis of variance. RSM was used to optimize the Re for the different number of BGA packages attached to the FPCB.

It is important to understand the behaviour of FPCB when exposed to both flow and thermal effects simultaneously under the operating conditions. Maximum d/L and von Misses stress were significantly affected by all parametric factors whilst (Nu)¯ is significantly affected by Re and thermal power. Optimized Re for 1–3 BGA packages with maximum thermal power applied has been identified as 21,364, 23,858 and 29,367, respectively.

This analysis offers a better interpretation of the parameter control in FPCB with optimized Re for the use of force convection electronic cooling. Optimal Re could be used as a reference in the thermal management aspect in designing the BGA package.

This research presents the parameters’ effects on the reliability and heat transfer in FPCB design. It also presents a method to optimize Re for the different number of BGA packages attached to increase the reliability in FPCB’s design.

This paper aims to introduce a new indicative parameter of filling efficiency to quantify the performance and productivity of the flip-chip underfill encapsulation process. Additionally, the variation effect of the bump pitch of flip-chip on the filling efficiency was demonstrated to provide insight for flip-chip design optimization.

The filling efficiency was formulated analytically based on the conceptual spatial and temporal perspectives. Subsequently, the effect of bump pitch on filling efficiency was studied based on the past actual-scaled and current scaled-up underfill experiments. The latter scaled-up experiment was validated with both the finite volume method-based numerical simulation and analytical filling time model. Moreover, the scaling validity of scaled-up experiment was justified based on the similarity analysis of dimensionless number.

Through the scaling analysis, the current scaled-up experimental system is justified to be valid since the adopted scaling factor 40 is less than the theoretical scaling limit of 270. Furthermore, the current experiment was qualitatively well validated with the numerical simulation and analytical filling time model. It is found that the filling efficiency increases with the bump pitch, such that doubling the bump pitch would triple the efficiency.

The new performance indicative index of filling efficiency enables the package designers to justify the variation effect of underfill parameter on the overall underfill process. Moreover, the upper limit of scaling factor for scaled-up package was derived to serve as the guideline for future scaled-up underfill experiments.

The performance of underfill process as highlighted in this paper was never being quantified before in the past literatures. Similarly, the scaling limit that is associated to the scaled-up underfill experiment was never being reported elsewhere too.

This paper focuses on the fluid-structure interaction (FSI) analysis of moisture induced stress for the flip chip ball grid array (FCBGA) package with hydrophobic and hydrophilic materials during the reflow soldering process. The purpose of this paper is to analyze the influence of moisture concentration and FCBGA with hydrophobic material on induced pressure and stress in the package at varies times.

The present study analyzed the warpage deformation during the reflow process via visual inspection machine (complied to Joint Electron Device Engineering Council standard) and FSI simulation by using ANSYS/FLUENT package. The direct concentration approach is used to model moisture diffusion and ANSYS is used to predict the Von-Misses stress. Models of Test Vehicle 1 (similar to Xie et al., 2009b) and Test Vehicle 2 (FCBGA package) with the combination of hydrophobic and hydrophilic materials are performed. The simulation for different moisture concentrations with reflows process time has been conducted.

The results from the mechanical reliability study indicate that the FSI analysis is found to be in good agreement with the published study and acceptable agreement with the experimental result. The maximum Von-Misses stress induced by the moisture significantly increased on FCBGA with hydrophobic material compared to FCBGA with a hydrophilic material. The presence of hydrophobic material that hinders the moisture desorption process. The analysis also illustrated the moisture could very possibly reside in electronic packaging and developed beyond saturated vapor into superheated vapor or compressed liquid, which exposed electronic packaging to higher stresses.

The findings provide valuable guidelines and references to engineers and packaging designers during the reflow soldering process in the microelectronics industry.

Studies on the influence of moisture concentration and hydrophobic material are still limited and studies on FCBGA package warpage under reflow process involving the effect of hydrophobic and hydrophilic materials are rarely reported. Thus, this study is important to effectively bridge the research gap and yield appropriate guidelines in the microelectronics industry.

The aim of this study is to investigate the effects of offset angle in wave soldering by using thermal fluid structure interaction modeling with experimental validation.

The authors used a thermal coupling approach that adopted mesh-based parallel code coupling interface between finite volume-and finite element-based software (ABAQUS). A 3D single pin-through-hole (PTH) connector with five offset angles (0 to 20°) on a printed circuit board (PCB) was built and meshed by using computational fluid dynamics preprocessing software called GAMBIT. An implicit volume of fluid technique with a second-order upwind scheme was also applied to track the flow front of solder material (Sn63Pb37) when passing through the solder pot during wave soldering. The structural solver and ABAQUS analyzed the temperature distribution, displacement and von Mises stress of the PTH connector. The predicted results were validated by the experimental solder profile.

The simulation revealed that the PTH offset angle had a significant effect on the filling of molten solder through the PCB. The 0° angle yielded the best filling profile, filling time, lowest displacement and thermal stress. The simulation result was similar to the experimental result.

This study provides a better understanding of the process control in wave soldering for PCB assembly.

This study provides fundamental guidelines and references for the thermal coupling method to address reliability issues during wave soldering. It also enhances understanding of capillary flow and PTH joint issues to achieve high reliability in PCB assembly industries.

The flexible printed circuit board (FPCB) can be an alternative to the rigid printed circuit board because of its excellent flexibility, twistability, and light weight. Using FPCB to construct personal computer (PC) motherboard is still rare. Therefore, the present study aims to investigate the fluid‐structure interaction (FSI) behaviors of the newly proposed FPCB motherboard under fan‐flow condition in the PC casings.

The deflection and stress induced, which are usually ignored in the traditional rigid motherboard, are the main concern in the current FPCB motherboard studies. Only a few studies have been conducted on the effect of inlet locations, effect of inlet sizes, effect of multi‐inlets, and effect of a two‐fan system. These numerical analyses are performed using the fluid flow solver FLUENT and the structural solver ABAQUS; they are real‐time online coupled by Mesh‐based Parallel Code Coupling Interface (MpCCI).

A smaller inlet size can cause higher deflection and stress fluctuations, but the fluctuations can be reduced by incorporating the multi‐inlets design. In addition, the inlet locations and two‐fan system can prominently affect the magnitudes of the deflection and stress induced.

The current study provides better understanding and allows designers to be aware of the FSI phenomenon when dealing with the FPCB motherboard. Although the present study primarily focuses on the motherboard, the findings could also contribute valuable information for other FPCB applications.

The present study extends the FSI investigation from the previous novel approach of FPCB motherboard, and uniquely explores the behaviors of the FPCB motherboard inside different PC casings.

This study aims to find out the problems of family Takaful (Islamic Life Insurance) operations in Bangladesh and proposes strategies to overcome the problems.

Qualitative data were collected through interviews with 32 respondents from two family Takaful operators in Dhaka, Bangladesh.

The study finds a number of problems of family Takaful which relate to the government, Takaful company and the Shariah board. Lack of governing guidelines for Takaful companies in Bangladesh is causing numerous operational problems of family Takaful. To overcome these obstacles, the government should propose separate Act for Takaful. This requires support from the stakeholders along with Islamic scholars in the country.

It is anticipated that the findings and suggestions of the study will assist the policymakers in improving the situation of family Takaful companies particularly in Bangladesh.

If the proposed suggestions are implemented in Takaful companies, the problems facing Takaful will likely be solved and more people will take part in Takaful. This would contribute to developing the country economically, raise Islamic values and foster peace and harmony in the society.

Mainly, this study is based on the primary research that has been conducted in family Takaful companies in Bangladesh.

There is a continuous drive in automotive sector to shift from conventional lubricants to environmental friendly ones without adversely affecting critical tribological performance parameters. Because of their favorable tribological properties, chemically modified vegetable oils such as palm trimethylolpropane ester (TMP) are one of the potential candidates for the said role. To prove the suitability of TMP for applications involving boundary-lubrication regime such as cam/tappet interface of direct acting valve train system, a logical step forward is to investigate their compatibility with conventional lubricant additives.

In this study, extreme pressure and tribological characteristics of TMP, formulated with glycerol mono-oleate (GMO), molybdenum dithiocarbamate (MoDTC) and zinc dialkyldithiophosphate (ZDDP), has been investigated using four-ball wear tester and valve train test rig. For comparison, additive-free and formulated versions of polyalphaolefin (PAO) were used as reference. Moreover, various surface characterization techniques were deployed to investigate mechanisms responsible for a particular tribological behavior.

In additive-free form, TMP demonstrated better extreme pressure characteristics compared to PAO and lubricant additives which are actually optimized for conventional base-oils such as PAO, are also proved to be compatible with TMP to some extent, especially ZDDP. During cylinder head tests, additive-free TMP proved to be more effective compared to PAO in reducing friction of cam/tappet interface, but opposite behavior was seen when formulated lubricants were used. Therefore, there is a need to synthesize specialized friction modifiers, anti-wear and extreme pressure additives for TMP before using it as engine lubricant base-oil.

In this study, additive-free and formulated versions of bio-lubricant are tested for cam/tappet interface of direct acting valve train system of commercial passenger car diesel engine for the very test time. Another important aspect of this research was comparison of important tribological performance parameters (friction torque, wear, rotational speed of tappet) of TMP-based lubricants with conventional lubricant base oil, that is, PAO and its formulated version.

A family takaful certificate is subscribed by a takaful participant for the purpose of preparing financial support for his dependants after his death. The takaful benefits could then be made payable to a nominee named as the beneficiary under conditional hibah (gift). In this respect, the participant is free to decide to whom the benefits are to be given since the law is silent as to the criteria of the beneficiary. This situation gives rise to the issue on whether such a practice fulfils the objectives of Sharīʿah, especially when the nominated beneficiary is not the sole dependant of the deceased participant. Therefore, this research aims to evaluate the status of family takaful benefits, analyse the rules of conditional hibah from the Sharīʿah perspective and propose solutions whenever necessary. The research adopts doctrinal analysis by examining existing primary and secondary materials including statutory provisions and other legal and non-legal literatures. The study predicates that the application of conditional hibah to the whole benefits does not reflect the objectives of Sharīʿah if determination on the status of the benefits is solely based on the nomination made by the participant. It is observed that takaful benefits payable from the Participant’s Account should be considered as the deceased’s estate and must be distributed according to fara’id or Islamic law of inheritance. Conversely, the sum covered payable from the Participant’s Special Account may be paid to the deceased’s dependants whose criteria are determined by the Sharīʿah Advisory Council as the highest authority in Islamic financial matters.

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.

Malaysia has shifted from a labor-intensive, agriculture-based economy since its independence in 1957 to a knowledge and innovation-based economy. Human capital development (HCD) is a key enabler for driving and sustaining Malaysia's socioeconomic growth. The education and training system is the main platform for HCD intervention. To sustain and achieve goals, long-term survival, competitive advantage, and sustainability, the workforce is optimized through comprehensive HCD interventions to provide the necessary knowledge, skills, and competencies needed to work effectively in a rapidly changing and complex environment. Numerous efforts have been made by the government to ensure that the education and training system has the capacity to enhance the quality and availability of intellectual and skilled human capital to support the transition toward knowledge-intensive activities, sustain economic growth, and compete in the global market. The country's development plans and policies as well as the economic development which lead toward a knowledge-based economy with a knowledge-based workforce have charted out clear transformation journeys for the development of the human capital ecosystem. This chapter presents an overview of the landscape of HCD in Malaysia. Relevant reports, plans, policies, and strategies to strengthen human capital through education and training is reviewed. Finally, a few issues and challenges that Malaysia experiences are discussed.