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The purpose of this paper is to propose new importance measures for degrading components based on Shapley value, which can provide answers about how important players are to the whole cooperative game and what payoff each player can reasonably expect.

The proposed importance measure characterizes how a specific degrading component contributes to the degradation of system reliability by using Shapley value. Degradation models are also introduced to assess the reliability of degrading components. The reliability of system consisting independent degrading components is obtained by using structure functions, while reliability of system comprising correlated degrading components is evaluated with a multivariate distribution.

The ranking of degrading components according to the newly developed importance measure depends on the degradation parameters of components, system structure and parameters characterizing the association of components.

Considering the fact that reliability degradation of engineering systems and equipment are often attributed to the degradation of a particular or set of components that are characterized by degrading features. This paper proposes new importance measures for degrading components based on Shapley value to reflect the responsibility of each degrading component for the deterioration of system reliability. The results are also able to give timely feedback of the expected contribution of each degrading component to system reliability degradation.

Joint reliability importance (JRI) of components is the effect of a change of their reliability on the system reliability. The authors consider two coherent multi-component systems – a series-in-parallel (series subsystems arranged in parallel) and a parallel-in-series (parallel subsystems arranged in series) system. It is assumed that all the components in the subsystems are independent but not identically distributed. The subsystems do not have any component in common. The paper aims to discuss these issues.

For both the systems, the expressions for the JRI of two or more components are derived. The results are extended to include subsystems where some of the components are replicated.

The findings are illustrated by considering bridge structure as a series-in-parallel system wherein some of the components are repeated in different subsystems. Numerical results have also been provided for a series-in-parallel system with unreplicated components. JRI for various combinations of components for both the illustrations are given through tables or figures.

Chang and Jan (2006) and Gao et al. (2007) found the JRI of two components of series-in-parallel system when the components are identical and independently distributed. The authors derive the JRI of m=2 components for series-in-parallel and parallel-in-series systems when components are independent but need not be identically distributed. Expressions are obtained for the above-mentioned systems with replicated and unreplicated components in different subsystems. These results will be useful in analyzing the joint effect of reliability of several components on the system reliability. This will be of value to design engineers for designing systems that function more effectively and for a longer duration.

In a globalised environment, market volatility makes risk management an essential component of the supply chain. Similar to conventional supply chains, a Halal supply chain (HSC) is also affected by several factors making it vulnerable to risks. Therefore, the purpose of this study is to identify and analyse the elements of Halal supply chain management (HSCM) and their significant risk dimensions.

In total, 72 risk elements of HSCM are identified through a review of contemporary scientific literature along with news items and official websites related to risk management of conventional supply chain management, HSC and sustainable supply chain. Further, 42 risk elements are finalised using fuzzy Delphi and then these risk elements are categorised into 7 dimensions. The interrelationships among the risk dimensions as well as risk elements are developed using fuzzy DEMATEL.

Results suggest that production, planning, logistic & outsourcing and information technology-related risk are prominent risk dimensions. The causal relationships among the significant risk dimensions and elements related to the HSCM may help managers and policy planners.

This study faces a challenge due to inadequate availability of the literature related to risk management in the area of HSCM. Further, this study has used inputs from experts, which can be biased.

To the best of the author's knowledge, it is the first comprehensive study towards investigating the interrelationships among the risks in the context of the HSCM.

The purpose of this study is to examine the impact of service-related independence impairments on perceptions of local and regional non-Big 4 Firms’ financial reporting reliability. This study is motivated by recent public policy, which proposes that service-related independence impairments may improve financial reporting reliability.

Commercial lending officers respond to a within-subjects experiment. The variables of interest are client importance, expertise and their related interaction. These variables are regressed on the perceived reporting reliability of local and regional firms.

Client importance is positively and significantly associated with the lenders’ selection of non-Big 4 firms, which supports Taylor et al.’s (2003) assertions that service-related independence violations improve financial reporting reliability. However, client importance is negatively associated with regional firms.

Client importance is significantly associated with regional firms only, which suggests that cross-sectional differences exist among non-Big 4 firms. The negative association between regional firms and client importance confirms Goldman and Barlev’s (1974) concerns that large firms are not exempt from client pressure. Client importance is also significantly (and positively) associated with lenders’ selection of the type of non-Big 4 firm to perform the engagement, which supports recent public policy’s proposal for joint attest and non-attest services (Exposure Draft for Statement for Accounting and Review Services No. 18).

The study overcomes within-subjects design limitations to provide a natural environment to understand lending officers’ perceptions of non-Big 4 firms. The results continue to fill the void in the literature which examines cross-sectional differences in non-Big 4 firm quality.

The purpose of this paper is to study the reliability of sintered nano-silver joints on bare copper substrates during high-temperature storage (HTS).

In this study, HTS at 250 °C was carried out to investigate the reliability of nano-silver sintered joints. Combining the evolution of the microstructure and shear strength of the joints, the degradation mechanisms of joints performance were characterized.

The results indicated that the degradation of the shear properties of sintered nano-silver joints on copper substrates was attributed to copper oxidation at the silver/copper interface and interdiffusion of interfacial elements. The joints decreased by approximately 57.4% compared to the original joints after aging for 500 h. In addition, severe coarsening of the silver structure was also an important cause for joints failure during HTS.

This paper provides a comparison of quantitative and mechanistic evaluation of sintered silver joints on bare copper substrates during HTS, which is of great importance in promoting the development of sintered silver technology.

This paper aims to present a machine learning framework for using big data analytics to predict the reliability of solder joints. The purpose of this study is to accurately predict the reliability of solder joints by using big data analytics.

A machine learning framework for using big data analytics is proposed to predict the reliability of solder joints accurately.

A machine learning framework for predicting the life of solder joints accurately has been developed in this study. To validate its accuracy and efficiency, it is applied to predict the long-term reliability of lead-free Sn96.5Ag3.0Cu0.5 (SAC305) for three commonly used surface finishes such OSP, ENIG and IAg. The obtained results show that the predicted failure based on the machine learning method is much more accurate than the Weibull method. In addition, solder ball/bump joint failure modes are identified based on various solder joint failures reported in the literature.

The ability to predict thermal fatigue life accurately is extremely valuable to the industry because it saves time and cost for product development and optimization.

This study aims to investigate simultaneous power and thermal loading.

Finite element method simulations coupled with experiments.

The effects of power cycling have been determined.

This paper aims to testify the combined effects of thermal and power cycling loads on the reliability of solder ball joints with barrel- and hourglass-type geometries in an electronic system. The finite element simulation outcomes showed that the maximum strain energy was accumulated at the edges of barrel-type solder, whereas the hourglass-type was vulnerable at the necking side. It was also found that the hourglass-type solder showed a reliable behavior when the sole thermal cycling was exerted to the electronic system, whereas the barrel-type solder was a better choice under simultaneous application of thermal and power loadings. The experimental results also confirmed the finite element simulation and indicated that the solder joint reliability strongly depends on the geometry of interconnection in different operating conditions. An extensive discussion was presented to shed light on the paramount importance of combined thermal/power cycling on the reliability of solder joints.

An overview has been presented on the topic of alternative surface finishes for package I/Os and circuit board features. Aspects of processability and solder joint reliability were described for the following coatings: baseline hot‐dipped, plated, and plated‐and‐fused 100Sn and Sn‐Pb coatings; Ni/Au; Pd, Ni/Pd, and Ni/Pd/Au finishes; and the recently marketed immersion Ag coatings. The Ni/Au coatings appear to provide the all‐around best options in terms of solderability protection and wire bondability. Nickel/Pd finishes offer a slightly reduced level of performance in these areas which is most likely due to variable Pd surface conditions. It is necessary to minimize dissolved Au or Pd contents in the solder material to prevent solder joint embrittlement. Ancillary aspects that include thickness measurement techniques; the importance of finish compatibility with conformal coatings and conductive adhesives; and the need for alternative finishes for the processing of non‐Pb bearing solders are discussed.

The purpose of this paper is to attempt to shift away from an exclusive probabilistic viewpoint or a pure network theory-based perspective for vulnerability assessment of infrastructure networks (INs), toward an integrated framework that accounts for joint considerations of the consequences of component failure as well as the component reliability.

This work introduces a fuzzy inference system (FIS) model that deals with the problem of vulnerability analysis by mapping reliability and centrality to vulnerability. In the presented model, reliability and centrality are first fuzzified, then 16 different rules are defined and finally, a defuzzification process is conducted to obtain the model output, termed the vulnerability score. The FIS model developed herein attempts to explain the linkage between reliability and centrality so as to evaluate the degree of vulnerability for INs elements.

This paper compared the effectiveness of the vulnerability score in criticality ranking of the components against the conventional vulnerability analysis methods. Comparison of the output of the proposed FIS model with the conventional vulnerability indices reveals the effectiveness of the vulnerability score in identifying the criticality of components. The model result showed the vulnerability score decreases by increasing reliability and decreasing centrality.

Two key practical implications for vulnerability analysis of INs can be drawn from the suggested FIS model in this research. First, the maintenance strategy based on the vulnerability analysis proposed herein will provide an expert facilitator that helps infrastructure utilities to identify and prioritize the vulnerabilities. The second practical implication is especially valuable for designing an effective risk management framework, which allows for least cost decisions to be made for the protection of INs.

As part of the first contribution, we propose a novel fuzzy-based vulnerability assessment model in building a qualitative and quantitative picture of the vulnerability of INs. The second contribution is especially valuable for vulnerability analysis of INs by virtue of offering a key to understanding the component vulnerability principle as being constituted by the component likely behavior as well as the component importance in the network.

This study aims to explore the dual identity role of joint gift-giving among adolescents. Studying this phenomenon through the lens of impression management theory enabled us to analyze private and group motives, drivers of these motives (givers’ public self-consciousness and self-monitoring and group cohesiveness) and the influence of group motives on the joint process. The characteristics of the joint process reflect a mutual social activity that enables adolescents to strengthen social group ties and define and nurture group identity. This research showed how a mutual consumer process, specifically, joint gift-giving, enhances the outcomes of social resources by defining groups’ mutual extended selves.

In this study, quantitative tools were used. Selection of constructs for the study was based on a literature review and existing qualitative research. To test the validity and the reliability of the scales, a convenience sample of 103 adolescents (13 to 16 years old) was used in a pre-test survey. In the main study, a convenience sample of 129 adolescences was used. Self-report questionnaires were distributed to adolescents (aged 13-16 years). The survey included scales covering private and group motives for joint gift-giving, givers’ personality, group cohesiveness and the characteristics of the joint process.

Givers’ public self-consciousness and self-monitoring were positively related to the motivation to engage in joint gift-giving to facilitate the development of desired private identities. High public self-consciousness and self-monitoring givers were motivated to enhance their private role in the group task and managed their impression among multiple audiences. We found that high-cohesiveness groups were motivated to nurture and strengthen social resources through joint gift-giving. Engaging in joint gift-giving is motivated not only by functional motives (e.g. saving money) but also by social motives that strengthen a group’s extended-self and social resources that all members enjoy.

Although gift-giving is a three-stage process per gestation presentation and reformulation stage, the current study explored joint gift-giving behavior only in the gestation stage. Future research should include the other two stages. Also the current research concentrated on adolescents. Exploring joint gift-giving among adults is recommended as well. Comparing the two age groups should allow a better understanding of the special characteristics of adolescents and adults. Additionally, other personality characteristics could affect givers private identity in the group task and other group characteristics such as group size gender of members and group context in the workplace could affect identity.

This research can provide marketers with a deeper understanding of the joint gift-giving process. For example, marketers should recognize that joint gift-giving involves adolescent groups’ time-consuming activities in the joint process, i.e. gift selection effort, making handmade gifts and putting special efforts in gift appearance that enable them to define and nurture their group identity.

Parents and educators should recognize the importance of social identity dual role in participating in joint gift-giving. Hence, we recommend them to encourage adolescents to participate in this joint consuming process to enable them to protect and define their identity.

Adolescents are an important market segment with unique cognitive, social and personality processes. While these processes have been explored in several consumer behavior studies, adolescents’ gift-giving has been largely ignored in the literature. This study contributes to an understanding of the drivers of private and group joint gift-giving motives, how sense of belonging and group identity are reflected in the social dynamics of joint gift-giving and how adolescents manage group and private impressions in the eyes of a single receiver and in the eyes of multiple peers participating in the group task.