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Complexity is the main challenge for present and future manufacturers. Assembly complexity heavily affects a product’s final quality in the fully automated assembly system. This paper aims to propose a new method to assess the complexity of modern automated assembly system at the assembly design stage with respect to the characteristics of both manufacturing system and each single component to be mounted. Aiming at validating the predictive model, a regression model is additionally presented to estimate the statistic relationship between the real assembly defect rate and predicted complexity of the fully automated assembly system.

The research herein extends the S. N. Samy and H. A. ElMaraghy’s model and seeks to redefine the predictive model using fuzzy evaluation against a fully automated assembly process at the assembly design stages. As the evaluation based on the deterministic scale with accurate crisp number can hardly reflect the uncertainty of the judgement, fuzzy linguistic variables are used to measure the interaction among influence factors. A dependency matrix is proposed to estimate the assembly complexity with respect to the interactions between mechanic design, electric design and process factors and main functions of assembly system. Furthermore, a complexity attributes matrix of single part is presented, to map the relationship between all individual parts to be mounted and three major factors mentioned in the dependency matrix.

The new proposed model presents a formal quantification to predict assembly complexity. It clarifies that how the attributes of assembly system and product components complicate the assembly process and in turn influence the manufacturing performance. A center bolt valve in the camshaft of continue variable valve timing is used to demonstrate the application of the developed methodology in this study.

This paper presents a developed method, which can be used to improve the design solution of assembly concept and optimize the process flow with the least complexity.

To find the system with minimum investment and best quality performance that is capable of producing all of the product variants, assessing the complexity of designing assembly system at the early concept stage is an essential step, which helps and instructs a designer to create a product- and system-oriented assembly solution with the least complexity. The purpose of this paper is to propose a quantifying measurement of complexity in the design of a modular automated assembly system.

The configurable assembly system is becoming a trend, which enables companies to quickly respond to changes caused by different product variants but without a large investment. One of the enabling factors is the availability of modular solutions of assembly modules that can be configured according to different technical requirements. This paper develops a methodology using fuzzy evaluation to calculate the design complexity in the design phase for a modular automatic assembly system. Fuzzy linguistic variables are used to measure the interaction among the influence factors, to deal with the uncertainty of the judgement. The proposed method investigates three matrices to present how the function-based assembly modules, design complexity factors, part attributes and product components, which are regarded as the main influence factors, complicate the construction of a modular assembly system. The design complexity is derived and quantified based on these assessments.

The proposed approach presents a formal quantification to evaluate the design complexity with regard to a modular assembly system from beginning, which can be identified and used as criteria to indicate the quality of performance and investment cost in advance. A mathematical model based on the fuzzy logic is established to provide both theoretical and practical guidance for the paper. To validate the predictive model, the statistic relationships between the assessed system design complexity, real assembly defect rate and investment cost are estimated based on regression analysis. The application of the presented methodology is demonstrated with regard to a traditional rear drive unit in the automotive industry.

This paper presents a developed method, which addresses the measures of complexity found in the design of a modular assembly system. It would help to run the design process with better resource allocation and cost estimation in a quantitative approach.

This study aims to optimise the effect of pre-oxidation on hot corrosion behaviour of Tribaloy T-900 at 900 °C in mixed Na₂SO₄ and K₂SO₄.

Prior to hot corrosion experiment, pre-oxidation treatments were carried in ambient air at 900 °C for 1, 5 and 10 h, respectively. The hot corrosion experiments were performed in a box type furnace at 900 °C. Both surfaces of specimens were brushed with saturated salt solution of 75 wt.% Na₂SO₄ + 25 wt.% K₂SO₄. After brushing, the salt-coated specimens were placed in electric stove to ensure drying of salt. After drying, presence of 3 mg/cm² salt on specimen’s surface was ensured through weighting.

The 1-h pre-oxidation treatment prior to hot corrosion showed superior hot corrosion resistance against molten salt attack. An optimum pre-oxidation time of 1 h helped timely formation of protective Cr₂O₃ layer and inhibited the formation of less stable and porous surface oxides of Ni and Mo during hot corrosion.

Pre-oxidation effect on hot corrosion behaviour of refractory metal (such as Mo in investigated alloy) containing alloy has never been reported previously. Refractory metals oxide (e.g. MoO3) could transform the corrosion phenomena to catastrophic failure through acidic fluxing.

This study aims to investigate the impacts of bank capital requirements on the performance and risk of the emerging economy, i.e. Bangladeshi banking sector.

The study applies an unbalanced panel data which comprises 30 banks yielding a total of 413 bank-year observations over the period 2000 to 2015.

Using generalized methods of moments, the empirical results of this research reveal that bank capital is positively and significantly impressive on bank performance, whereas negatively and significantly impact on risk. The study also finds the inverse relationship between risk and performance in both the performance and risk equations. The results also indicate that there is a persistence of performance and risk from one year to the next year.

This is the unique investigation on Bangladeshi bank industry that considers the simultaneous effect of bank capital requirements on risk and performance. Therefore, it is predicted that the empirical evidence of this research shows policy implications to the regulatory authority of Bangladeshi banking industry to determine relevant policies.

This study aims to explore the repost features of microblogs acting to promote the information diffusion of government-generated content on social media.

This study proposes a topic−sentiment analysis using a mixed social media analytics framework to analyse the microblogs collected from the Sina Weibo accounts of 30 Chinese provincial police departments. On the basis of this analysis, this study presents the distribution of reposted microblogs and reveals the reposting characteristics of police-generated microblogs (PGMs).

The experimental results indicate that children’s safety and crime-related PGMs with a positive sentiment can achieve a high level of online information diffusion.

This study is novel, as it reveals the reposting features of PGMs from both a topic and sentiment perspectives, and provides new findings that can inspire users’ reposting behaviour.

The purpose of this paper is to explore the Chinese microblog users’ psychological motivations and the association between users’ motivations and their offline civic and political engagement. Specifically, this study examines what the psychological impetuses of Weibo use are and how they promote the young citizens’ civic and political involvement.

The data were collected through the web-based survey with a total sample of 426 people. Principal components factor analysis, correlation analysis, and hierarchical multiple regressions were sequentially carried out to address the research questions.

The findings reveal that there are four major motives for using Weibo: information, socializing, recognition seeking and entertainment. Interestingly, seeking social needs is positively and significantly related to increasing young people’s civic participation, but not political participation.

Theoretically, the research demonstrates that the uses and gratifications is a suitable approach for analysis of psychological antecedents of Weibo use and subsequent outcomes. Practically, it will help understand the dynamics of how the new media technology may engender democratic development and change.

Although the growing significance of social media has drawn considerable attention, little research has been conducted to assess the political consequences of Weibo. The current study fills the void by investigating whether Weibo functions as an effective tool to facilitate democratic engagement in contemporary China. The obtained results may provide insight into the relationship between the gratification structures and engagement in other social settings.

Due to the size and importance of social media, user-generated content analysis is becoming a key factor for companies and brands across the world. By using Twitter messages’ content, the purpose of this paper is to identify which elements of the messages enable tweet diffusion and facilitate eWOM.

In total, 30,082 tweets collected from 10,120 Twitter users were classified based on four assorted brands. By comparing with multiple regression techniques high vs low purchase involvement and hedonic vs utilitarian products and using the theory of heuristic-systematic processing of information, the authors examine the causes of tweet diffusion.

The authors illustrate how the elements of a tweet (hashtags, mentions, links, sentiment or tweet length) influence its diffusion and popularity.

This study validated the use of information processing theories in the social media field. The study showed a picture on how different Twitter elements influence eWOM and message diffusion under several purchase involvement situations.

The results of this study can help social media brand community managers of all types of companies on how to write their Twitter messages to obtain greater dissemination and popularity.

The study offers a unique deep brand analysis which helps brands and companies to understand their social media popularity in detail. Depending on product category, companies can achieve maximum social impact on Twitter by focusing on the interactivity items that will work best for their products or brands.

The purpose of this paper is to study the effect of vapor assembly sequence and assembly temperature on the corrosion protection of the complex silane films Al alloy. The performance and application range of silane films are enhanced.

The complex silane films were successfully prepared on the surface of aluminum alloy using via vapor phase assembly of 1,2,3-benzotriazole (BTA) and dodecyltrimethoxysilanes (DTMS). The protection of the assembly films against corrosion of Al alloy is investigated by the electrochemical measurements and the alkaline solution accelerated corrosion test. Thickness and hydrophobicity of the complex films are studied using ellipsometric spectroscopy and contact angle tests.

It shows that the anti-corrosion ability of the complex films is overall superior to that of the single-component assembled films. DTMS-BTA films have larger thickness and best anti-corrosion ability. The alkyl chains in DTMS have better compatibility with BTA molecules. The rigid BTA molecule can permeate into the long alkyl chain of DTMS as fillers and improve the barrier properties of the complex films.

In this paper, a green and efficient method of vapor phase assembly is proposed to rust prevention during manufacture of Al alloy workpiece.

The authors aimed to identify the opinions of young adult consumers regarding food processing companies’ (FPCs) credibility in terms of food safety (FS).

The authors surveyed Generation Z (GenZ) consumers. The authors assessed the reliability of the research questionnaire using Cronbach’s alpha statistics. The authors used descriptive statistics and one-way ANOVA analysis of variance in the data analysis to determine intergroup variability. The authors performed statistical analyses using IBM SPSS Statistics. 27.

The most valued determinants for consumers were competence and skills, and the most valued family members’ opinions on FS, followed by experts’ opinions. FS concerns are more associated with FPCs than with farmers. The ethics of conduct and moral responsibility play an important role in assessing the FPCs’ credibility.

The questionnaire did not focus on specific food industries, such as fruit and vegetables, fish, meat, dairy, etc. In the future, a similar survey on producers’ credibility should consider the issue of FS risks associated with the specifics of a particular industry.

The authors proposed a set of factors that may determine young adult consumers’ perception of the FPCs’ credibility, which they may use for research within other consumer groups.