Search results

The purpose of this paper is to investigate the effect of carbon nanotube (CNT) addition on microstructure, interfacial intermetallic compound (IMC) layer and micromechanical properties of Sn-3.0Ag-0.5Cu (SAC305)/CNT/Cu solder joint under blast wave condition. This work is an extension from the previous study of microstructural evolution and hardness properties of Sn-Ag-Cu (SAC) solder under blast wave condition.

SAC/CNT solder pastes were manufactured by mixing of SAC solder powder, fluxes and CNT with 0.02 and 0.04 by weight percentage (Wt.%) separately. This solder paste then printed on the printed circuit board (PCB) with the copper surface finish. Printed samples underwent reflow soldering to form the solder joint. Soldered samples then exposed to the open field air blast test with different weight charges of explosives. Microstructure, interfacial IMC layer and micromechanical behavior of SAC/CNT solder joints after blast test were observed and analyzed via optical microscope, field emission scanning microscope and nanoindentation.

Exposure to the blast wave induced the microstructure instability of SAC305/Cu and SAC/CNT/Cu solder joint. Interfacial IMC layer thickness and hardness properties increases with increase in explosive weight. The existence of CNT in the SAC305 solder system is increasing the resistance of solder joint to the blast wave.

Response of micromechanical properties of SAC305/CNT/Cu solder joint has been identified and provided a fundamental understanding of reliability solder joint, especially in extreme conditions such as for military applications.

Reflow solder joint quality is significantly affected by the ability of the solder to perfectly fill pad space and retain good solder joint shape. This study aims to investigate solder joint quality by quantitatively analyzing the stencil printing-deposited solder volume, solder height and solder coverage area.

The dispensability of different solder paste types on printed circuit board (PCB) pads using different stencil aperture shapes was evaluated. Lead-free Type 4 (20–38 µm particle size) and Type 5 (15–25 µm particle size) solder pastes were used to create solder joints according to standard reflow soldering.

The results show that the stencil aperture shape greatly affects the solder joint quality as compared with the type of solder paste. These investigations allow the development of new strategies for solving solder paste stencil printing issues and evaluating the quality of solder joints.

The reflow soldering process requires the appropriate selection of the stencil aperture shape according to the PCB and the solder paste according to the particle-size distribution of the solder alloy powder. However, there are scarce studies on the effects of stencil aperture shape and the solder alloy particle size on the solder paste space-filling ability.

The purpose of this paper is to discuss the effect of a blast wave on the microstructure, intermetallic layers and hardness properties of Sn0.3Ag0.7Cu (SAC0307) lead-free solder.

Soldered samples were exposed to the blast wave by using trinitrotoluene (TNT) explosive. Microstructure and intermetallic layer thickness were identified using Alicona ® Infinite Focus Measurement software. Hardness properties of investigated solders were determined using a nanoindentation approach.

Microstructure and intermetallic layers changed under blast wave condition. Hardness properties of exposed solders decreased with an increase in the TNT explosive weight.

Microstructural evolution and mechanical properties of the exposed solder to the blast wave provide a fundamental understanding on how blast waves can affect the reliability of a solder joint, especially for military applications.

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.

With the arrival of the 4th Industrial Revolution and the Education 4.0 era, the inevitability of educators using technology in the classroom has grown. A global health pandemic has hastened the adoption of online teaching. The interdependence of technologies and pedagogies necessitates vigour and variability, along with evolving teaching and learning practices. Past literature has advocated for various roles and forms of technology in education; however, inconsistencies in “blended learning” definitions have posed challenges in understanding blended learning’s full potential. Thus, a quantitative meta-analysis was conducted to examine the efficacies and outcomes of blended learning.

A quantitative meta-analysis was conducted to examine the efficacies and outcomes of blended learning. A total of 96 samples were carefully chosen based on established theoretical definitions, relevant to technology use. The samples were then placed into three categories: Web-based applications, standalone applications and devices. Effect sizes (ESs) acquired from Cohen’s d formula (1988; 1992) were used to determine overall effectiveness. The ES of individuals in each of the delivery platform categories was totalled and averaged. This combined ES was then interpreted using Cohen’s (1988) benchmark. Subsequently, a combination of ESs was compared based on the similar type of delivery method, as well as the dependent variables in which the average of the respective combined ESs was calculated for interpretation.

Findings show that all three delivery methods were effective in enhancing a learner’s performance, especially for language teaching and learning. The study provides insights that can assist stakeholders in selecting different delivery platforms to befit the needs of discrete disciplines.

The researchers recommend the three categories of technological intervention described above as tangible tenets for future research in blended learning implementation. Thus far, no blended learning researcher has attempted to categorize the myriad of technological interventions available into concrete, concise groupings. With the recommended categories of technological intervention, blended learning practitioners would have a better sense of direction in the context of investigating the effectiveness of a specific intervention implemented. The researchers deem the recommended categories of technological intervention as immensely useful for the blended learning community to begin establishing intervention as one of the important elements to look at. For example, the effectiveness of a technological intervention under both the Web-based application and standalone application categories, respectively, in relation to a similar dependent variable can be compared to further understand the implications of using interventions of a different nature. And such studies will need to extend the investigation to the present by examining all recent studies.

Number of disastrous events are rising globally, and it is important to manage the humanitarian supply chain management process to assist the disaster affected individuals in terms of relief operations. Effective relief operations can help to recover the materialistic loss due to any disaster. But there is a paucity of studies regarding this issue for developing countries. This study, hence, inspected the factors that affect the disaster supply chain management (DSCM) processes for relief operations in Bangladesh.

This study examined the factors affecting relief operations through a qualitative analysis. This study used thematic analysis. Interviews were conducted with related supply chain individuals who were triangulated by data from related publications and blogs.

The study showed that sustainable DSCM for relief operations in Bangladesh require addressing few factors as organizational capabilities, warehousing locations and inventory management, infrastructure facility, coordination among partners, government and local authority support to create a transparent, efficient, effective and sustainable DSCM process for relief operations in Bangladesh. The system loopholes can be identified and rectified on the base of these factors.

The number of interview respondents was limited to twenty who were selected randomly from four organizations. To create a sustainable disaster supply chain management (SCM) for relief operations few factors were considered as predominant factors in Bangladesh context to generalize the developing country contexts and other factors were not considered. Therefore, for farther humanitarian research, the model of this study can be used for quantitative research and the hypotheses can be tested empirically to get more acute findings.

As this study identifies the factors which can help to create a sustainable DSCM system for relief operations, hence practically, Bangladesh humanitarian SCM agencies will be beneficial from this study. They can easily recognize the factors need to be considered to create a sustainable DSCM process for relief operations.

This is a unique study carried out to examine the factors affecting DSCM process for relief operations in Bangladesh.

Recently, several areas are successfully applying the Lean Six Sigma methodology, specifically in healthcare, public services, higher education institutions and manufacturing industries. This study aims to present an extensive literature review involving Lean Six Sigma practical applications in the last five years, described in a case studies format.

A systematic literature review was conducted, and 39 articles were selected and analyzed.

An increase in Lean Six Sigma applications in healthcare and higher education institutions was identified. Furthermore, Lean Six Sigma is effectively applied in several areas and is continuously used in traditional industries. The main critical success factor identified was leadership and management involvement, project management and organizational infrastructure, as well as training and education. Also, the main difficulties found are related to the organization's culture and developing communication with leaders and managers.

The main difficulties found in this research are related to the lack of data presented in some articles analyzed, where only information about how the Lean Six Sigma application was conducted is shown, not mentioning difficulties or success factors identified.

Case studies are fundamental to help popularize Lean Six Sigma applications, showing a real-life scenario of how the methodology is implemented, the main difficulties encountered and critical success factors found. Thus, the value of this study is promoting and developing research involving Lean Six Sigma case study applications to guide new researchers and practitioners on the subject.

The purpose of this paper is to propose the conceptual relationship between competency and effectiveness of internal Shariah auditors in Islamic financial institutions (IFIs).

Normative and theorizing based on the main sources of Islam, mainly Maqasid al-Shariah theory, has been utilized in this research.

This study demonstrated how Maqasid al-Shariah or higher objectives of Islamic law have gradually captured the attention of increasing numbers of modern Muslim scholars for solving contemporary issues.

This study uniquely captured Maqasid al-Shariah for the competency of internal Shariah auditor.

The purpose of this paper is to establish the halal certification–logistics performance relationship by means of developing a theoretical model and to suggest areas for future research undertakings. The relationship between various forms of certification and logistics performance has been reported in many logistics literature. However, there is paucity in research concerning the relationship between halal certification and logistics performance.

The literature representing the concept of halal, halal logistics, institutional support and logistics performance are synthesised to develop a framework. Two distinguished management theories, namely, the resource-based view (RBV) and institutional theory, set the foundation of the proposed theoretical framework.

The paper suggests that proper application of resources, in this case halal certification, could positively influence logistics performance. The paper asserts that governmental factors act as the moderator between the halal certification–logistics performance relationship, or could directly influence logistics performance.

The paper presents a synthesis of previously unconnected variables of halal certification and logistics performance, and integrates the RBV and institutional theories as the basis for a theoretical framework. However, the proposed theoretical framework requires further validation through the supports of additional empirical research.

Apart from implementing halal certification as a tool to gain business legitimacy, the paper offers insights to logistics service provider as to how halal certification can be used as a mechanism to improve organisational performance, particularly logistics performance.

This paper is one of the first to establish the relation between halal certification and logistics performance and highlights the prominent role of government support as an independent and moderating factor. It constitutes a preliminary argument that entices research within the halal certification and halal logistics spectrum.

The purpose of this paper is to analyse the internal and external factors related to the disclosure of environmental information in universities which reflect the actions carried out in these universities.

Taking as reference the first 200 universities in the Shanghai ranking, several factors associated with the degree of environmental information disclosure in universities – governance dimension, the relationship and participation of stakeholders, position and prestige as signs of the quality of the institution and cultural concern in the university’s country for the environment – are analysed.

The results obtained show that the size of the leadership team, stakeholder participation, the position of the university in rankings and cultural concern in the university’s country for the environment are determining factors in the university’s environmental actions and, consequently, in their disclosure. Other factors – such as the size of the university, the level of self-financing and financial autonomy – do not affect the disclosure of environmental information.

Scant research exists on the environmental commitments of universities; this paper aims to fill that gap. Their role as the main channel of research and as instructors of future professionals makes them points of reference in society. Research on university ranking has traditionally focussed on teaching and research results, but environmental issues are becoming increasingly important. This paper enumerates the factors that influence the dissemination of environmental information in the most prestigious universities. This research also provides an original approach by considering not only top-down but also bottom-up strategies through communication channels and the incidence of cultural factors.