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The purpose of this paper is to investigate the thermomechanical response of four well-known lead-free die attach materials: sintered silver, sintered nano-copper particles, gold-tin solders and silver-tin transient liquid phase (TLP) bonds.

This examination is conducted through finite element analysis. The mechanical properties of all die attach systems, including elastic and Anand creep parameters, are obtained from relevant literature and incorporated into the numerical analysis. Consequently, the bond stress-strain relationships, stored inelastic strain energies and equivalent plastic strains are thoroughly examined.

The results indicate that silver-tin TLP bonds are prone to exhibiting higher inelastic strain energy densities, while sintered silver and copper interconnects tend to possess higher levels of plastic strains and deformations. This suggests a higher susceptibility to damage in these metallic die attachments. On the other hand, the more expensive gold-based solders exhibit lower inelastic strain energy densities and plastic strains, implying an improved fatigue performance compared to other bonding configurations.

The utilization of different metallic material systems as die attachments in power electronics necessitates a comprehensive understanding of their thermomechanical behavior. Therefore, the results of the present paper can be useful in the die attach material selection in power electronics.

In power electronics, there are various metallic material systems used as die attachments. The complete understanding of the thermomechanical behavior of such interconnections is very important. Therefore, this paper aims to examine the thermomechanical response of four famous die attach materials, including sintered silver, sintered nano-copper particles, gold-tin solders and silver-tin transient liquid phase (TLP) bonds, using nonlinear finite element analysis.

During the study, the mechanical properties of all die attach systems, including elastic and viscoplasticity parameters, are obtained from literature studies and hence incorporated into the numerical analysis. Subsequently, the bond stress–strain relationships, stored inelastic strain energies and equivalent plastic strains are thoroughly examined.

The results showed that the silver-tin TLP bonds are more likely to develop higher inelastic strain energy densities, while the sintered silver and copper interconnects would possess higher plastic strains and deformations. Suggesting higher damage to such metallic die attachments. The expensive gold-based solders have developed least inelastic strain energy densities and least plastic strains as well. Thus, they are expected to have improved fatigue performance compared to other bonding configurations.

This paper extensively investigates and compares the mechanical and thermal response of various metallic die attachments. In fact, there are no available research studies that discuss the behavior of such important die attachments of power electronics when exposed to mechanical and thermomechanical loads.

In this study, we examine the impact of audit protection services on individual taxpayer decision making. Audit protection services provide additional support for taxpayers in the event of an audit including preparation and representation. While these services could provide taxpayers with additional confidence, such services could also foster greater reliance on tax software, possibly resulting in riskier tax decisions. Drawing on risk homeostasis theory, we investigate two factors that could affect taxpayer reliance: the amount of taxes owed and the extent of audit protection services. Our results indicate that taxpayers are more likely to rely on tax software prompts when there are full audit protection services and a greater amount of taxes owed. Further, we find that the provision of full audit protection services reduces the likelihood that taxpayers change their tax reporting behavior. Collectively, we provide evidence on taxpayer interactions with tax software.

The construction industry is widely recognized as one of the most hazardous sectors in the world. Despite extensive research on safety management, a critical issue remains that insufficient attention is devoted to safety practices in rural areas. Notably, accidents frequently occur during the construction of rural self-built houses (RSH) in China. Safety management tends to be overlooked due to the perceived simplicity of the construction process. Furthermore, it is essential to acknowledge that China currently lacks comprehensive laws and regulations governing safety management in RSH construction. This paper aims to analyze the behavior of key stakeholders (including households, workmen, rural village committee and the government) and propose recommendations to mitigate safety risks associated with RSH construction.

This paper applies evolutionary game theory to analyze the symbiotic evolution among households, workmen and rural village committee, in situations with or without government participation. Additionally, numerical simulation is utilized to examine the outcomes of various strategies implemented by the government.

Without government participation, households, workmen, and rural village committee tend to prioritize maximizing apparent benefits, often overlooking the potential safety risks. Numerical simulations reveal that while government involvement can guide these parties towards safer decisions, achieving the desired outcomes necessitates the adoption of reasonable and effective strategies. Thus, the government needs to offer targeted subsidies to these stakeholders.

Considering that during the construction phase, stakeholders are the main administrators accountable for safety management. However, there exists insufficient research examining the impact of stakeholder behavior on RSH construction safety. This study aims to analyze the behavior of stakeholders about how to reduce the safety risks in building RSH. Thus, the authors intend to contribute to knowledge in this area by establishing evolutionary game model. Firstly, this study carried out a theoretical by using tripartite evolutionary game to reveal the reasons for the high safety risk during building RSH. Practically, this research points out the important role of households, workmen and rural village committee in improving safety management in rural areas. Besides, some suggestions are proposed to the government about how to reduce construction safety risks in rural areas.

Modern warfare and modern battlefield are very demanding. The recent conflicts showed that the usage of the helicopters is very limited and only the best constructions are able to provide support for the operations. The purpose of this research is to show the possibilities of new design tool for main rotor aerostructural optimization. It is a next chapter of the research that is aimed at finding new solutions for rotorcraft constructions.

This work presents a method of preliminary structure optimization of the main rotor blade using parametric modeling. It is the next step in the main rotor optimization studies. It is the next step after preparing the parametric model for the external shape CFD analysis. As a basis for parametric blade structure calculations, the analytical model is provided in this paper. The equations of rigid blade loads and, as a consequence of the strength elements, stresses are shown. The parametric blade modeling is conducted using the Graphic Integrated Programming language. The parametric design method is shown to be used for various blade planform models and different section airfoils. The structure of a blade is generated automatically after the user enters the parameters. The code-inbuilt analysis systems provide a quick inertia examination of the generated geometry, which is the basis for further optimization. The program calculates the blade loads and verifies them with the given material conditions and proposed safety factors. In the analysis, composite materials for the strength elements were proposed.

The results of this research showed the application of parametrization into the main rotor blade design loop. It was presented that the main rotor blade structure can be enhanced using fluid-structure interaction (FSI) methods. The time saving with the implementation the process into design loop is shown.

This work can be practically used in the main rotor blade design process. It provides the possibilities to check various blade aerodynamic configuration in a structure strength aspect.

To the best of the authors’ knowledge, there were no published research that combines the main rotor FSI analysis. The method, which is presented in the work, provides a new approach to a rotorcraft design. The application of the parametrization and combining it with the FSI method gives a novel solution for helicopters construction enhancement.

The study aims to understand the relationship between facilitating, demoting, motivating factors and visit intention; and to clarify the role of death anxiety before visiting a dark exhibition.

Partial least squares structural equation modeling was adopted to analyze data from 426 potential visitors to the Capuchin Crypt in Rome (Italy).

Results demonstrate that dark fascination, prestige, reflection on death and mortality and interpersonal facilitators are the main drivers of visit intention, and structural constraints are the main demoting factors. Contrary to expectations, intrapersonal constraints have a positive influence on motivators and indirectly on visit intention, and death anxiety has mixed results.

Data collection from only one dark exhibition requires that the generalization of the results must be done with care.

Conclusions enabled a better understanding of pre-trip tourist behavior, providing valuable suggestions for the communication strategy of Destination Management Organizations (DMOs) and site managers.

The study adopts a consolidated and empirical approach to studying facilitators, motivators, constraints and visit intention, as well as the effect of death anxiety. To the best of the author’s knowledge, this is the first study to develop a comprehensive investigation of these four constructs, whether at the darker or the lighter end of the dark tourism spectrum. Consequently, it offers a better understanding of lighter dark attractions, which allows DMOs and others to improve the communication of their tourism products.

The recognition of housing as an essential requirement in enhancing the quality of life of an individual has increasingly captivated scholars’ interest, particularly within the context of sustainability. However, the identification of suitable attributes of sustainable housing to be prioritized encountered challenges due to a lack of effective approach in addressing uncertainties and stakeholders’ interests. This study attempts to identify critical attributes of sustainable housing in rural areas and explore their interrelationships.

Six dimensions and 54 criteria are proposed and validated using the expert linguistic preferences through the Fuzzy Delphi Method. The Fuzzy Decision-Making Trial Evaluation Laboratory is also applied to determine the interrelationship between those attributes.

The result demonstrates that economic benefits strongly impacted social implications for sustainable housing. The top criteria, including government participation, reduced life cycle cost, environmental protection and local authorities’ participation, are considered to assist housing stakeholders for better sustainable practices.

To the best of the authors’ knowledge, this is one of the first studies addressing the interrelationship among sustainable housing attributes through linguistic preferences in the context of rural areas.

This paper aims to explore the extent and characteristics of Canadian university reporting of and policy regarding greenhouse gas emissions from air travel. It identifies current approaches’ details and limits and recommends improvements.

The study developed questions and considerations for analysing reporting and policy, reviewed university documents and webpages and contacted university staff.

Roughly 20% of Canadian universities report flight emissions. Figures vary by factors of over 100 even when normalized or expressed as a percentage of institutional emissions. Inter-university differences in data collection and emissions calculation practices shape reporting. Canadian university air travel emissions cannot be meaningfully compared. Few universities have flight emissions reduction policies; those that do leave relevant decisions to individuals. These approaches do not respond adequately to the emissions reduction challenge.

This study is the first comprehensive survey of university flight emissions reporting for any country. Its original framework highlights calculation’s complexities. It recommends standardizing reporting process information disclosure, reporting flight emissions as a range and faculty leadership of emissions reduction efforts.

Loneliness is widely prevalent in modern society. Despite the growth in studies, very limited studies so far have attempted to systematically review the literature. This study aims to consolidate the antecedents of loneliness by reviewing the literature.

The systematic literature review method is adopted to identify the antecedents. Full texts of each article were taken for analysis which was published from 2002 to 2022. Multiple databases were examined and total of 60 articles were included for systematic literature review.

The study presents the descriptive analysis of the articles. Also, the paper thematically presents the key antecedents of loneliness in three themes (a) Loss of love, (b) Individual cognitive and personal factors and (c) Childhood experiences and parenting practices. The study also highlights the moderating effect of demographic factors and lifestyle changes.

The current study is the first systematic literature review to present the antecedents of loneliness. The study contributes by offering an enhanced understanding of loneliness. Also, the study presents contemporary understanding of loneliness and proposes a conceptual framework. The findings are useful to academicians as well as policymakers.