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Due to the miniaturization of electronic devices, the increased current density through solder joints leads to the occurrence of electromigration failure, thereby reducing the reliability of electronic devices. The purpose of this study is to propose a finite element-artificial neural network method for the prediction of temperature and current density of solder joints, and thus provide reference information for the reliability evaluation of solder joints.

The temperature distribution and current density distribution of the interconnect structure of electronic devices were investigated through finite element simulations. During the experimental process, the actual temperature of the solder joints was measured and was used to optimize the finite element model. A large amount of simulation data was obtained to analyze the neural network by varying the height of solder joints, the diameter of solder pads and the magnitude of current loads. The constructed neural network was trained, tested and optimized using this data.

Based on the finite element simulation results, the current is more concentrated in the corners of the solder joints, generating a significant amount of Joule heating, which leads to localized temperature rise. The constructed neural network is trained, tested and optimized using the simulation results. The ANN 1, used for predicting solder joint temperature, achieves a prediction accuracy of 96.9%, while the ANN 2, used for predicting solder joint current density, achieves a prediction accuracy of 93.4%.

The proposed method can effectively improve the estimation efficiency of temperature and current density in the packaging structure. This method prevails in the field of packaging, and other factors that affect the thermal, mechanical and electrical properties of the packaging structure can be introduced into the model.

Polymer-based thermal interface materials (TIMs) are having pump out problem and could be resolved for reliable application. Solid-based interface materials have been suggested and reported. The purpose of this paper is suggesting thin film-based TIM to sustain the light-emiting diode (LED) performance and electronic device miniaturization.

Consequently, ZnO thin film at various thicknesses was prepared by chemical vapour deposition (CVD) method and tested their thermal behaviour using thermal transient analysis as solid TIM for high-power LED.

Low value in total thermal resistance (R_th-tot) was observed for ZnO thin film boundary condition than bare Al boundary condition. The measured interface (ZnO thin film) resistance {(R_th-bhs) thermal resistance of the interface layer (thin film) placed between metal core printed circuit board (MCPCB) board and Al substrates} was nearly equal to Ag paste boundary condition and showed low values for ZnO film prepared at 30 min process time measured at 700 mA. The T_J value of LED mounted on ZnO thin film (prepared at 30 min.) coated Al substrates was measured to be 74.8°C. High value in junction temperature difference (ΔT_J) of about 4.7°C was noticed with 30 min processed ZnO thin film when compared with Al boundary condition. Low correlated colour temperature and high luminous flux values of tested LED were also observed with ZnO thin film boundary condition (processed at 30 min) compared with both Al substrate and Ag paste boundary condition.

Overall, 30 min CVD processed ZnO thin film would be an alternative for commercial TIM to achieve efficient thermal management. This will increase the life span of the LED as the proposed material decreases the T_J values.

The purpose of this paper is to illustrate the new technical demands and reliability challenges to printed circuit board (PCB) designs, materials and processes when the transmission frequency increases from Sub-6 GHz in previous generations to millimeter (mm) wave in fifth-generation (5G) communication technology.

The approach involves theoretical analysis and actual case study by various characterization techniques, such as a stereo microscope, metallographic microscope, scanning electron microscope, energy dispersive spectroscopy, focused ion beam, high-frequency structure simulator, stripline resonator and mechanical test.

To meet PCB signal integrity demands in mm-wave frequency bands, the improving proposals on copper profile, resin system, reinforcement fabric, filler, electromagnetic interference-reducing design, transmission line as well as via layout, surface treatment, drilling, desmear, laminating and electroplating were discussed. And the failure causes and effects of typical reliability issues, including complex permittivity fluctuation at different frequencies or environments, weakening of peel strength, conductive anodic filament, crack on microvias, the effect of solder joint void on signal transmission performance and soldering anomalies at ball grid array location on high-speed PCBs, were demonstrated.

The PCB reliability problem is the leading factor to cause failures of PCB assemblies concluded from statistical results on the failure cases sent to our laboratory. The PCB reliability level is very essential to guarantee the reliability of the entire equipment. In this paper, the summarized technical demands and reliability issues that are rarely reported in existing articles were discussed systematically with new perspectives, which will be very critical to identify potential reliability risks for PCB in 5G mm-wave applications and implement targeted improvements.

Guided by stimulus-organism-response (SOR) theory, this study analyzed the user-generated content (UGC) produced by attendees from six anime conventions in the USA.

A total of 739 online reviews and 1,932 photos were collected from the social platforms of six large anime conventions in the USA (Yelp and Facebook), and the study employed thematic analysis and image analysis to analyze the collected UGCs.

The findings revealed eight main themes (i.e. ambient and space, customers, service and products, sign and symbol, social density, emotional status, motivation, and behavior intention) and 32 subthemes across the three dimensions of SOR theory. Leveraging the power of cutting-edge image analysis, the image labels obtained from the analysis contributed to the creation of network clusters. The result of the image analysis also continued consistently with the thematic analysis result, which reflected SOR theory.

Theoretically, the study applied SOR theory and blended thematic and image analyses to gain a comprehensive understanding of anime convention attendees’ experience and categorized the attendees’ emotional status as positive or negative to reflect their overall evaluation. Practically, this study highlighted some complaints from attendees and provided suggestions for operators. However, the study focused only on large anime conventions in the USA; future studies should compare attendees’ experiences with small and large conventions or anime conventions worldwide.

The study utilized UGCs to understand the key patterns essential to attendees during anime conventions in the USA and applied SOR theory to its investigation.

Crowded urban regions pose a complex urban challenge that can adversely affect urban residents, encompassing aspects like mental and physical well-being, overall livability and quality of life. The complexity in determining the factors influencing the crowding perception, which encompass subjective and situational psychological factors alongside physical and environmental attributes, imparts ambiguity to planners' approach. This study aims to unravel the intricate interplay between crowding and the physical attributes inherent in the built environment.

This literature review analyses theories linking urban planning and environmental psychology to uncover gaps in the relationship between urban design principles and residents' perceptions of crowding. It also explores influential variables affecting crowding perception and diverse methodologies across contexts.

The study built upon a broad literature review which is expected to summarise and classify the variables of urban planning components and approaches according to their impacts on the psychological perception of crowding. Furthermore, highlighting a number of recommendations that can be considered a guide for planners and urban designers to enhance the urban experience and reduce the perception of crowding.

This study seeks to improve the overall experience of crowding in densely populated urban areas. It accomplishes this by identifying influential factors and comprehending the associated outcomes in such contexts. Furthermore, it bridges perspectives from various fields to examine relevant policies and strategies to mitigate crowding consequences.

With corporate social responsibility (CSR) becoming mandatory, several firms in India have been compelled into spending resources on CSR while their business strategy and processes were unprepared to take up CSR activities, effectively. In this light, the CSR relationship with other business functions would be altered. Using Thomson Reuters data from 2010 to 2018 (pre-mandate to post-mandate) this study aims to re-examine the relationship between CSR and financial performance.

The current study is rooted in the bandwagon-bias effect theory and uses a long-term data (2010–2018) of Indian firms. It uses Refinitiv Thomson Reuters ESG rating to measure CSR and accounting measures for financial performance (FP) to make a pre-post analysis of the impact that mandatory CSR regime has had on firms performance. The study uses the weighted panel regression method.

The relationship between CSR and FP is different when CSR was voluntary than when it has been mandated by Law. CSR has a positive effect over the FP during the voluntary phase but this positive relationship weakens during the mandatory phase. The waning effect of CSR over FP substantiates the presence of bandwagon bias effect which can be explained by the crowding-in of several companies engaged in CSR activities because of the mandatory CSR law.

Few countries have made CSR mandatory therefore CSR literature is limited. But mandating CSR is a growing phenomenon so this study augments to the body of knowledge. Until now literature generally converged on a positive relationship between CSR performance and FP but the current study shows altering directions to this relationship in a changing CSR environment. The use of the bandwagon-bias theory contributes to the theoretical approaches. Theoretically, the findings add to the body CSR literature and offer impetus to the evolving domain of impact measurement and reporting.

Results of the study offer a clear indication to managers that they need to re-strategise their CSR activities during the mandatory CSR environment if they wish to draw instrumental benefits of a positive impact on the FP of their firms. CSR expenditure is now a leveller so managers may either exceed the mandatory 2% expenditure as some firms did during the voluntary CSR phase or else design their CSR implementation plans to bring about a more impactful positive change. Communicating the impact of CSR to influential and powerful stakeholders beyond the mandatory reporting to the government is yet another way through which managers can draw benefits of CSR activities. Additionally to draw positive results from CSR activities firms may consider adopting international reporting and benchmarking standards such as the GRI and ISO 26000. Finally, the results of the study can be used by policymakers to make a note that the CSR law is causing a weakening of the financial benefits and therefore.

The results of the study can be used by policymakers also need to make a note that the CSR law is causing a weakening of the financial benefits and therefore firms are adopting shortcuts, by donating the required amount of funds. But donation of funds defeats the real purpose of mandatory CSR which is social impact, therefore the regulators may want to make the necessary changes unplug the gaps in the CSR law to ensure better adherence to the law in spirit and a real impact on the ground activities.

While CSR–FP relationship has been extensively explored but limited studies have explored this relationship in a mandatory CSR environment and no other work presents a comparative view of the CSR–FP relationship, namely, before and after the mandatory CSR policy. The current study is one of the limited few studying the impact of mandatory CSR policy on FP, and the only one that uses the bandwagon-bias effect to explain the phenomenon of weakening impact of CSR on FP of firms. Bandwagon-bias effect has been used in studying consumer behaviour, where group effect impacts behaviour of individuals and with mandatory CSR policy, firms following the other firms leading to crowding in. Using the bandwagon-bias effect has found limited attention from the CSR scholars, the current study uses this theoretical basis and therefore augments the CSR literature.

By focussing on the anticipated emotional reactions of volunteers and drawing on theories of motivation and identity, this study investigates how volunteers react to different options of the entrepreneurial model of Amigos for Children Foundation (ACF). The paper proposes a hypothetical model for volunteer’s emotional reactions to potential business model changes. We suggest the relative importance of intrinsic motivational factors, professional identity and attitudes towards business organisations as mediating variables. ACF works exclusively with university students as volunteers, so their specific characteristics may limit some of the conclusions and propositions of this qualitative research, but public policy consequences of supporting similar entrepreneurial transitions can be generally relevant.

Based on the qualitative analysis of semi-structured interviews with volunteers of ACF, a Hungarian non-profit organisation, we explore the challenges of transitioning into a social enterprise.

Previous research showed controversial results about the impact of pay on the motivations of volunteers. For a non-profit organisation that would like to utilise the competencies of its volunteers, introducing a market-based service may mean additional financial resources and the potential loss of human resources. Understanding the moderating factors of volunteers' reactions might help build better theories for managing the non-profit-social enterprise transition and designing public policies to support scaling up the impact of successful social purpose organisations.

For practitioners, the research underlines the importance of participatory mechanisms in volunteer management. By managing transitions better, non-profit organisations can expand their social impact by acquiring more financial resources through market-based activities closely related to their original activities and keeping their volunteers. The study elucidates the relevance of the crowding-out effect and indicates some hypothetical moderating variables influencing its potential degree.

The study analyzes the relationship between homeownership and financial investment of households in the context of emerging markets like India. It also examines how homeownership affects the portfolio decisions of Indian households.

Using the nationally representative All-India Debt and Investment Survey of 2019 and employing an instrumental variable approach, the authors analyze the relationship between homeownership and the share of financial assets held by Indian households. The study also employs several sensitivity checks, including alternate estimation techniques and alternative definitions of the housing variables, and accounts for additional factors to ensure that the authors are able to capture the effect of homeownership on the outcome variable.

The analysis suggests homeownership crowds out financial investment in India due to high repair and maintenance costs. The negative effect is mainly observed in urban households. Further, the findings imply that homeownership leads households to reallocate their asset portfolio. Homeowners have a lower share in liquid short term deposits, indicating the high liquidity risk of their portfolios. On the other hand, homeownership increases the share of long term retirement funds along with no effect on risky asset share. The authors observe that the crowding out effect is more striking for younger households and poorer households with low income, and the effect is lower for indebted households.

The findings underscore the need for financial awareness programs so that housing does not crowd out liquid investments of households. Additionally, the results highlight that policies should first focus on young and poor households as the negative effect is more prominent for these groups. Finally, there is scope for policies to support repair and maintenance costs incurred by vulnerable households to reduce the negative effect of housing on liquid financial investments.

This paper is among the few studies that provide insights into how homeownership relates to financial investment and portfolio decisions in the context of an emerging economy. Furthermore, the heterogeneous effects based on poor economic status and age underscore the need for complementary policies.

The aim of this research is to determine the price fairness of the social servicescape and the effect of price fairness on customer trust. In this context, first of all, the effect of the social servicescape on price fairness and then the effect of price fairness on customer trust were tested.

The universe of the research consists of people who visit Starbucks coffee stores. In the study, data were collected from 338 people who visited Starbucks coffee stores. The relationships between the variables were analyzed using the Structural Equation Modeling (SEM) Technique.

As a result of the research, it was concluded that employees, other customers and social crowds, which are from the dimensions of the social servicescape, do not have a significant effect on price fairness, the interaction between employee and customer, which is from the sub-dimensions of the social servicescape, has an effect on customers' perception of price fairness, and price fairness also has an effect on customer trust.

The important point in this research is to determine the effect of the social servicescape on price fairness, which has not been studied in the literature before. Although the effect of physical servicescape on price justice has been investigated, the effect of social servicescape on price justice has not been investigated. When evaluated from this point of view, it is thought that the research will have an important contribution to the literature.

Overcrowding continues to afflict emergency departments (EDs), and its attendant consequences are becoming increasingly severe. The burden of the COVID-19 pandemic is further escalating the situation worldwide. One of the most critical questions is how to adequately quantify what constitutes overcrowding and determine implications for operations management in improving service efficiency. This paper aims to discuss the aforementioned.

The authors propose the time and class complexity measures for ED service systems, taking into account important patient-level and system characteristics. Using an extensive data set from a Canadian ED, the authors investigate the performance of complexity-based measures in predicting service delays.

The authors find that the complexity measure is potentially more important than some well-known crowding metrics. In particular, EDs can improve service efficiency by managing the level of complexity within a desirable interval. Furthermore, complexity exposes how the interplay between demand-side behavioral changes and supply-side responses affects operational performance. Moreover, the results suggest that arrival patterns—the number of patients of each class arriving per time and times between events (arrivals and service completions)—increase the risk of service delays more than the demand volume.

This paper is the first to provide an extensive investigation into the application of the complexity-based measure for ED crowding. The study demonstrates potential values to be gained in ED service systems if complexity measure is incorporated into their operations management decisions.