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The purpose of this paper is to investigate the wettability and intermetallic (IMC) layer formation of Sn-3.0Ag-0.5Cu (SAC305)/CNT/Cu solder joint according to the formulation of solder paste because of different types of fluxes.

Solder pastes were prepared by mixing SAC305 solder powder with different flux and different wt.% of carbon nanotube (CNT). Fourier transform infrared spectroscopy was used to identify functional groups from different fluxes of as-formulated solder paste. The solder pastes were then subjected to stencil printing and reflow process. Solderability was investigated via contact angle analysis and the thickness of cross-sectionally intermetallic layer.

It was found that different functional groups from different fluxes showed different physical behaviour, indicated by contact angle value and IMC layer thickness. “Aromatic contain” functional group lowering the contact angle while non-aromatic contain functional group lowering the thickness of IMC layer. The higher the CNT wt.%, the lower the contact angle and IMC layer thickness, regardless of different fluxes. Relationship between contact angle and IMC layer thickness is found to have distinguished region because of different fluxes. Thus it may be used as guidance in flux selection for solder paste formulation.

However, detail composition of the fluxes was not further explored for the scope of this paper.

The quality of solder joint of SAC305/CNT/Cu system, as indicated by contact angle and the thickness of IMC layer formation, depends on existence of functional group of the fluxes.

The purpose of this paper is to investigate the relationship between microstructure and varied strain rates towards the mechanical properties and deformation behaviour of Sn-3.0Ag-0.5Cu (SAC305) lead-free solder wire at room temperature.

Tensile tests with different strain rates of 1.5 × 10⁻⁶, 1.5 × 10⁻⁵, 1.5 × 10⁻⁴, 1.5 × 10⁻³, 1.5 × 10⁻² and 1.5 × 10⁻¹ s⁻¹ at room temperature of 25°C were carried out on lead-free Sn-3.0Ag-0.5Cu (SAC305) solder wire. Stress-strain curves and mechanical properties such as yield strength, ultimate tensile strength and elongation were determined from the tensile tests. A microstructure analysis was performed by measuring the average grain size and the aspect ratio of the grains.

It was observed that higher strain rates showed pronounced dynamic recrystallization on the stress-strain curve. The increase in the strain rates also decreased the grain size of the SAC305 solder wire. It was found that higher strain rates had a pronounced effect on changing the deformation or shape of the grain in a longitudinal direction. An increase in the strain rates increased the tensile strength and ductility of the SAC solder wire. The primary deformation mechanism for strain rates below 1.5 × 10⁻¹ s⁻¹ was grain boundary sliding, whereas the deformation mechanism for strain rates of 1.5 × 10⁻¹ s⁻¹ was diffusional creep.

Most of the studies regarding the deformation behaviour of lead-free solder usually consider the effect of the elevated temperature. For the current analysis, the effect of the temperature is kept constant at room temperature to analyze the deformation of lead-free solder wire solely because of changes of strain rates, and this is the originality of this paper.

This paper aims to investigate the characteristics of ultra-fine lead-free solder joints reinforced with TiO₂ nanoparticles in an electronic assembly.

This study focused on the microstructure and quality of solder joints. Various percentages of TiO₂ nanoparticles were mixed with a lead-free Sn-3.5Ag-0.7Cu solder paste. This new form of nano-reinforced lead-free solder paste was used to assemble a miniature package consisting of an ultra-fine capacitor on a printed circuit board by means of a reflow soldering process. The microstructure and the fillet height were investigated using a focused ion beam, a high-resolution transmission electron microscope system equipped with an energy dispersive X-ray spectrometer (EDS), and a field emission scanning electron microscope coupled with an EDS and X-ray diffraction machine.

The experimental results revealed that the intermetallic compound with the lowest thickness was produced by the nano-reinforced solder with a TiO₂ content of 0.05 Wt.%. Increasing the TiO₂ content to 0.15 Wt.% led to an improvement in the fillet height. The characteristics of the solder joint fulfilled the reliability requirements of the IPC standards.

This study provides engineers with a profound understanding of the characteristics of ultra-fine nano-reinforced solder joint packages in the microelectronics industry.

The findings are expected to provide proper guidelines and references with regard to the manufacture of miniaturized electronic packages. This study also explored the effects of TiO₂ on the microstructure and the fillet height of ultra-fine capacitors.

This paper aims to analyze the effect of Au wire size and location of hook during wire pulling test to identify the variation of results obtained.

Two hook locations, namely, location A and location B were used to analyze the effect of hook location. Location A was the same as the hook location required by MIL-STD-883E standard, whereas location B was located near to the second bond. The correlation between new purposed failure modes and MIL-STD-883E standard was developed to reflect on the pull strength with the physical failure.

It was observed that fine pitch Au wire has higher variation and lower process capability of pull strength. Au wire pulled by the hook at location B provides a more representative result compared to that at location A. Fifty per cent or more of Au remnant is required to be considered as a good and reliable Au wedge bond based on the new purposed failure modes.

The evaluation of gold (Au) wedge bond requires a new proper wire pulling test method. This is due to the large variation obtained from the application of current practice of wire pulling test.

This paper aims to investigate the influence of temperature and lignin concentration on the inhibition of carbon steel corrosion in 1 M HCl.

Weight loss corrosion tests were performed at different temperatures in the range of 30-70°C (303-343 K).

It was found that the corrosion inhibition efficiency (IE) of lignin on the carbon steel decreased when the temperature was increased from 60 to 70°C. However, at lower temperatures ranging from 30 to 50°C, the IE improved, due to occurrence of lignin adsorption on the surface of metal specimens. The IE was higher with increasing lignin concentration, thus reducing the weight loss of the carbon steel. The adsorption phenomenon involved exothermic processes because the value of enthalpy of adsorption (ΔH°_ads) < 0 and Gibbs free energy of adsorption (ΔG°_ads) were less negative with increase in temperature. The entropy of adsorption (ΔS°_ads) had negative values, representing the decrease in disorder of adsorption. The adsorption of lignin on the carbon steel surface in 1 M HCl was comprehensive, as deduced from kinetic and thermodynamic parameters. However, physisorption was the major contributor in the inhibition mechanism. The inhibitive features of carbon steel surfaces showed less damage once the steel was treated in lignin, as evident from macroscopy images.

The use of lignin as an acid corrosion inhibitor at high temperature is practical in metal surface treatment process.

The use of organic compounds gives an advantage to the environment, universal health and save cost, as the compounds can be found in nature.

Lignin can act as a flexible corrosion inhibitor within the temperature range of 30-70°C in 1 M HCl because it exhibits comprehensive adsorption (i.e. a combination of both physisorption and chemisorption) at specific concentrations.

Islamic finance and Halal product sectors are thriving successfully. This chapter is a general review of the perception of Asian consumers on Islamic finance and Halal sectors in the global Halal economy.

The first section will briefly describe the Halal concept in both Islamic finance and Halal industries, and the growth of both sectors in Asian countries. The second part highlights the review of Asian consumers’ perception towards Islamic finance products and Halal products.

The review found that the consumers’ perception towards the Islamic finance products and Halal products is distinctive. This is due to the diversity of Asian countries in terms of geography, religion, culture, ethnic, school of thoughts (madzahib), income per capita and government’s involvement.

The third part of the chapter concentrates on planning towards Halal marketing, which involves the move and future challenges in different layers of industries to gear up and strengthen the Halal economy.

The purposes of this study were to measure the relevance status of Index Islamicus, evaluate the semantic correlation between a query and documents and inquire the basis of its rank. Sorting the retrieved results from the most relevant to the least relevant is the common option of an information retrieval system. This sorting mechanism or relevance judgment is computed by measuring closeness of query with its documents.

Forming up 100 queries on Islamic History and Civilizations, with two indexing elements (keyword and concept), a laboratory experiment was generated on its first ten items of the rank. Throughout an experimental research design, the relevance status value formula was used to measure system-computed rank and compare it with mean average precision.

The results showed that the average status value of Index Islamicus’s ranking on relevance criterion was 18 per cent effective in terms of retrieving precise documents. Despite the main focus of this study being only on one subject domain and the items calculated were only 1,000, this small percentage of its ranking mechanism proved that semantic correlations between queries with subject domain did not achieve the satisfactory level.

Implication of this study could be a guideline for further research on ranking mechanism of other search engines because the limitation of this study was Index Islamicus being the only database, which was the focus of this study.

Throughout this study, Index Islamicus would be benefited knowing the status of its ranking mechanism as well as other databases can make further research on their own ranking method following this study.

Researchers and vendors of online databases can ensure their users a true platform of search engine with a proper ranking list.

Relevance status value model for Index Islamicus on Islamic History and Civilization that allows the system to rank documents according to the match between document and query and gives the idea of a better index. The model improves the system’s ranking mechanism, and promotes the use of semantic relationships. This research promotes the computation of relevance status value by domain for capturing subject-specific relevance criteria and semantic relationships.

Objective of the study is to determine the factors effecting successful women leadership and to draw a comparison between Thailand and Malaysia. Primary data were collected from both countries. Quantitative research approach was used in this study by using a cross-sectional research design. Population of the study was based on the textile companies of Thailand and Malaysia. Employees of textile companies were selected as the respondents. Partial Least Square (PLS) was used for data analysis. Results of the study found that learning autonomy, emotional intelligence, political differences and organization culture (OC) are the major factor which effect on successful women leadership in both countries. Moreover, in both countries, learning autonomy, emotional intelligence and OC have positive role in successful women leadership, however, political differences effect negatively on successful women leadership. Additionally, there is a difference between both countries, in case of moderating role of political differences and OC. In Thailand, OC has positive role to enhance women leadership through emotional intelligence. In case of Malaysia, political differences weaken the positive relationship between the emotional intelligence and successful women leadership.

The provision of meals has long been regarded as an essential part of treatment of hospitalized patients complementing medical procedures and nursing management. Today, despite changes in the health-care landscape, which focused on improving the quality and efficiency of hospital care, malnutrition among inpatient was still a common worldwide concern.

This was a multi-centre, randomized study conducted in 21 study sites comprising 21 state and specialist government hospitals under the Ministry of Health, Malaysia. The sample size for this study was calculated with purposive sampling method, followed by proportionate sampling to determine the random sample size of each of the study sites. The total sample size required for this study was 2,759 subjects. A validated data collection form was used in the study.

Only 32.2 % and 37.6 % of subjects achieved adequate energy and protein intake, respectively, during their admission to medical ward. The study result showed that the overall mean energy and protein intake was 794.6 ± 487.8 kcal and 35.2 ± 24.3 g, respectively. The estimated energy (p = 0.001) and protein (p = 0.001) intake of all study sites was significantly lower compared to the adequacy value.

The adequacy intake in this study was only carried out in medical wards, thus reproducible result among other wards in different study sites could not be confirmed. Besides, this study assumed that the portion eaten by subjects during lunch and dinner was the same, and therefore, either one was recorded together with breakfast and either lunch or dinner to represent a subject’s daily intake.

This was the first nationwide study to report the adequacy of energy and protein intake of patients receiving therapeutic diets in the government hospital setting in Malaysia.

This study aims to explore and conceptualize metaverse adoption using a systematic literature review (SLR). It also aims to propose a conceptual model that identifies significant factors affecting metaverse adoption in the entertainment, education, tourism and health sectors.

A SLR was conducted using the “preferred reporting items for systematic reviews and meta-analyses” report protocol and the “theory, context, characteristics, methods” framework to include all relevant articles published up to March 2023, which were sourced from the Scopus and Web of Science databases.

The reviewed literature revealed that the countries with the highest publications in the field of metaverse were China and the USA. It was also found that the technology acceptance model was the most used theoretical framework. Survey-based research using purposive and convenience sampling techniques emerged as the predominant method for data collection, and partial least square-structural equation modeling was the most used analytical technique. The review also identified the top six journals and the variables that help to develop a proposed model.

This review presents a novel contribution to the literature on metaverse adoption by forming a conceptual model that incorporates the most used variables in the entertainment, education, tourism and health sectors. The possible directions for future research with identified research gaps were also discussed.