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The paper aims to study the effect of sintering temperature on the microstructure, shear strength and ratcheting fatigue life of nanosilver sintered lap shear joint. In addition, the Gerber model is used to predict the ratcheting fatigue lives of nanosilver sintered lap shear joints at different sintering temperatures.

In this paper, the nanosilver sintered lap shear joints were prepared at three sintering temperatures of 250 °C, 280 °C and 310 °C. The bonding quality was characterized by scanning electron microscopy, X-ray diffraction, transmission electron microscope and shear tests, and the long-term reliability was studied by conducting ratcheting fatigue tests. In addition, three modified models based on Basquin equation were used to predict the ratcheting fatigue life of nanosilver sintered lap shear joint and their accuracies were evaluated.

When the sintering temperature is 250°C, the nanosilver sintered lap shear joint shows the porosity of 22.9 ± 1.6 %, and the shear strength of 22.3 ± 2.4 MPa. Raising the sintering temperature enhances silver crystallite size, strengthens sintering necks, thus improves shear strength and ratcheting fatigue life in joints. In addition, the ratcheting fatigue lives of the joints sintered at different temperatures are effectively predicted by three equivalent force models, and the Gerber model shows the highest life prediction accuracy.

The sintered silver bondline is suffering a complex stress state. The study only takes the shear stress into consideration. The tensile stress and the combination of shear stress and tensile stress can to be considered in the future study.

The paper provides the experimental and theoretical support for robust bonding and long-term reliability of sintered silver structure.

The introduced model can predict the ratcheting fatigue lives of the joints sintered at different temperatures, which shows a potential in engineering applications.

The study revealed the relationship between the sintering temperature and the microstructure, the shear strength and the ratcheting fatigue life of the joint. In addition, the Gerber model can predict the ratcheting fatigue life accurately at different sintering temperatures.

This paper aims to use nano-silver paste to design a new bonding method for super-large-area direct-bonded-aluminum (DBA) plates. It compared several frequently used bonding methods and proved the feasibility of an optimized low-pressure-assisted double-layer-printed silver sintering technology for large-area bonding to increase the thermal conductivity of power electronic modules with high junction temperature, higher power density and higher reliability.

The bonding profile was optimized by using transparent glasses as substrates. Thus, the bonding qualities could be directly characterized by optical observation. After sintering, the bonded DBA samples were characterized by nondestructive X-ray computed tomography system, scanning electron microscopy equipped with an energy dispersive spectrometer. Finally, bonding stress evolution was characterized by shear tests.

Low-pressure-assisted large-area double-layer-printed bonding process consisting of six-step was successfully developed to bond DBA substrates with the size of 50.8 × 25.4 mm. The thickness of the sintered-silver bond-line was between 33  and 74 µm with the average porosity of 12.5 per cent. The distribution of shear strength along the length of DBA/DBA bonded sample was from 9.7  to 18.8 MPa, with average shear strength of 15.5 MPa. The typical fracture primarily propagated in the sintered-silver layer and partially along the Ni layer.

The bonding stress needs to be further improved. Meanwhile, the thermal and electrical properties are encouraged to test further.

If nano-silver paste can be used as thermal interfacial material for super-large-area bonding, the thermal performance will be improved.

The paper accelerated the use of nano-silver paste for super-large-area DBA bonding.

The proposed bonding method greatly decreased the bonding pressure.

Green building (GB) maintenance is increasingly accepted in the construction industry, so it can now be interpreted as an industry best practice for maintenance planning. However, the performance competency and design knowledge of the practice's building control instrument process can be affected by its evaluation and the information management of building information modelling (BIM)–based model checking (BMC). These maintenance-planning problems have not yet been investigated in instances such as the Grenfell Tower fire (14 June 2017, approximately 80 fatalities) in North Kensington, West London.

This study proposes a theoretical framework for analysing the existing conceptualisation of BIM tools and techniques based on a critical review of GB maintenance environments. These are currently employed on GB maintenance ecosystems embedded in project teams that can affect BMC practices in the automation system process. In order to better understand how BMC is implemented in GB ecosystem projects, a quantitative case study is conducted in the Malaysian public works department (Jabatan Kerja Raya (JKR)).

GB ecosystem projects were not as effective as planned due to safety awareness, design planning, inadequate track insulation, environmental (in) compatibility and inadequate building access management. Descriptive statistics and an ANOVA were applied to analyse the data. The study is reinforced by a process flow, which is transformed into a theoretical framework.

Industry practitioners can use the developed framework to diagnose BMC application issues and leverage the staff competency inherent in an ecosystem to plan GB maintenance environments successfully.

This paper aims to identify the different system approach using building information modelling (BIM) technology that is equipped with automated evaluation processes. BIM research has mainly focused on theoretical models of acceptance in the green building (GB) maintenance industry. However, BIM has the potential to the competency’s performance and design knowledge of building control instrument. Realising this potential requires a study of BIM at the maintenance planning level, which is considered to be BIM-based model checking (BMC). BMC and its effect in the maintenance planning have not been sufficiently investigated.

The aim of this paper is to present a critical review of literature on the theoretical background of BMC practices and the main features of information and communication technology tools and techniques in the GB maintenance projects.

A theoretical framework of BMC is developed and presented. The proposed model incorporates requirement for maintaining a competency’s performance on maintenance planning schemes of GB projects and the importance of early integration of BMC in the design phase to identify alternative methods to cogenerate, monitor and optimise BMC.

It is found that variables facilitating BMC are integrated at different GB maintenance environments levels and are shaped by the context. Directions for future research are presented.

Most green building (GB) materials, which are used widely in the construction sector in Malaysia, perform poorly in terms of energy efficiency and sustainability. Nevertheless, during maintenance planning of these materials, the focus is often directed towards comfort and design instead. However, as GB material construction projects grow in scale and complexity, interconnections between the activities and processes can be noticed during problematic planning performance management to monitor the GB material components for corrective and preventive maintenance actions.

The concept of GB material maintenance planning for sustainable development and the main features of information and communication technology tools and techniques are based on analysis of literature reviews of GB material scenarios.

The results show how decision-making support in maintenance planning can be unsuccessful and how planning decisions can frame the content of an integrated system to analyse information and reduce risks of GB material failure.

The paper concludes that implementing a research framework for developing such a system can help improve the sustainable performance of maintenance planning of GB material economic, social and environmental issues.

The green building (GB) maintenance industry has been under increasing pressure by designers to demonstrate its evaluation and information management of building information modelling based model checking (BMC) to the competency's performance and design knowledge of building control instrument. This main problem has been termed as maintenance planning level. Although maintenance planning has been explored in GB maintenance environments, less is known about what maintenance planning problems currently exist and what their causes are, such as the recent fire in the Grenfell Tower (14 June 2017, about 80 fatalities) in North Kensington, West London. The aim of this paper is to identify how GB maintenance environments could integrate BMC within their processes. The purpose of this study is to assess the BMC technology management of GB maintenance ecosystem and that of a soft skills level to establish the impact of innovation policy features on database and safety risk function mechanism.

To achieve this aim, a comprehensive literature review of the existing conceptualisation of BMC practices is reviewed and the main features of Information and Communication Technology tools and techniques currently being employed on such GB maintenance ecosystem is carried out to evaluate the strengths and weaknesses of the previous studies. The conceptual framework explores the importance of integration of BMC in the construction phase to identify alternative methods in the automation system (AS) process to co-generate, monitor and optimise BMC.

The results confirm that BMC tool positively influences database application and risk mechanism of construction project safety while agreeableness negatively does. Besides, database application has a negative influence on innovation policy of company towards BMC implementation. Propositions derived not only shed light on guidance for future research on the soft skills of construction organisations, but also provide decision-making support through a better understanding of the factors affecting soft skills level amongst biggest construction companies.

Thus far, this study advances the knowledge about how GB maintenance environments can ensure BMC delivery. This paper highlights the need for further research to integrate BMC in GB maintenance environments validates the framework across the construction phase with different GB project managers and engineers.