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Micro-holes are drilled and plated in flexible printed circuit boards (FPCs) for connecting circuits from different layers. More holes, with diameters smaller than 0.3 mm, are required to be drilled in smaller areas with flexible circuits’ miniaturization. The micro-hole quality of micro-drilling is one of the biggest issues of the flexible circuit manufacturers’ production. However, it is not easy to control the quality of micro-holes. The purpose of this study was to conduct research on the tool wear characteristics of FPC drilling process and its influence on micro-hole quality to improve the micro-hole quality of FPC.

The tool-wear characteristics of micro-drills after FPC drilling were observed. The influence of spindle speed, feed rate, number of drilled holes and entry board materials on tool-wear was analyzed. The hole qualities of FPC micro-drilling were measured and observed. The relationship between tool-wear and hole quality was analyzed.

The result showed that the tool-wear characteristics of FPC micro-drilling was similar to the tool-wear characteristics of rigid printed circuit board (RPC) micro-drilling. Abrasive wear occurred on both the main cutting edges and the chisel edges of micro-drills, even though there was no glass fiber reinforcing the cloth inside FPC. Resin adhesion was observed on the chisel edge. The influence of feed and number of drilled holes on tool-wear was significant. Tool-wear significantly influences the hole quality of FPC. Tool-wear will largely decrease the hole position accuracy of FPC micro-holes. Tool-wear will increase the thickness of PI nail heads and the height of exit burrs. Fracture was the main difference between tool wear of FPC and RPC micro-drilling. Resin adhesion of RPC was much more severe than FPC micro-drilling. Increasing the spindle speed properly may improve tool life and hole quality.

The technology and manufacturing of FPC has been little investigated. Research on micro-drilling FPC and research data is lacking so far. The micro-hole quality directly affects the reliability of FPC. Thus, improving the micro-hole quality of FPC is very important.

This paper aims to investigate the impacts of rumors' information characteristics on people's believing and spreading of rumors online.

This study employed a mixed-methods approach by combining qualitative and quantitative methods. In study 1, the authors explored different types of rumors and their information source characteristics through qualitative research. In study 2, the authors utilized the findings from study 1 to develop an empirical model to verify the impact of these characteristics on the public's behaviors of believing and spreading rumors by content analysis and quantitative research.

The results show that five information source characteristics – credibility, professionalism, attractiveness, mystery and concreteness – influence the spreading effect of different types of rumors.

This study contributes to rumor spreading research by deepening the theory of information source characteristics and adding to the emerging literature on the COVID-19 pandemic.

Insights from this research offer important practical implications for policymakers and online-platform operators by highlighting how to suppress the spread of rumors, particularly those associated with COVID-19.

This research introduces the theory of information source characteristics into the field of rumor spreading and adopts a mixed-methods approach, taking COVID-19 rumors as a typical case, which provides a unique perspective for a deeper understanding of rumor spreading's antecedences.

The development of the digital age has made data and information more transparent, enhancing the strategic perspectives of both buyers (strategic waiting) and sellers (price fluctuations) in their decision-making. This research investigates the optimal dynamic pricing strategy of the content product developer in relation to their consideration of consumer fairness concerns to elucidate the impact of consumer fairness concerns on the dynamic pricing strategy of the developer.

This paper assumes that monopolistic content developers implement a dynamic pricing strategy for the content product. Through constructing a two-period dynamic pricing game model, this research investigates the optimal decisions of the content developer, contingent upon their consideration or disregard of consumer fairness concerns. In the extension section, the authors additionally account for the influence of myopic consumers on these optimal decisions.

Our findings reveal that the degree of consumer fairness concerns significantly influences the developer’s optimal dynamic pricing decision. When a developer offers content products with lower depth, there is a propensity for the developer to refrain from incorporating consumer fairness concerns into a dynamic pricing strategy. Conversely, in cases where the developer offers a high-depth content product, consumer fairness concerns benefit the developer. Furthermore, our analysis reveals a consistent benefit for the developer from the inclusion of myopic consumers.

Few studies have delved into the conjoined influence of consumer fairness concerns and strategic behavior on dynamic pricing strategy. Our findings indicate that consumer fairness concerns can enhance the efficiency of the value chain for content products under specific conditions. This paper not only enriches the existing literature on dynamic pricing by incorporating consumer fairness concerns theoretically but also offers practical insights. The outcomes of this research can guide content product developers in devising optimal dynamic pricing strategies.

The purpose of this study is to explore the adjustment model of expatriates in overseas projects by studying two overseas projects of a Chinese state-owned enterprise.

Based on the grounded theory, qualitative analysis was performed based on data compiled from 116 pieces of project briefings, 105 questionnaires answered by expatriate workers and 21 interviews conducted to those workers based on briefings and questionnaires.

The study found that the simulated home is a standard cross-cultural adjustment model for expatriates in Chinese engineering projects, which are project-oriented and often inattentive to employees' individual rights. The simulated home creates a unique work-place and social environment similar to that of expatriates' home country in the cultural setting of the host country, but it also establishes a cultural barrier, limiting the communication between expatriates and the local people, which is not conducive to the cultural exchange between the two sides, causing cultural clashes and consequently hindering the progress of projects.

This research puts forward the model of “simulated home.” And this study bears significance to the cross-cultural adjustment of expatriate workers in Chinese overseas projects.

The flexible printed circuit (FPC) board with the characteristic of light and thin strengthened confronted the growing miniaturization requirements of the electronic product and the popularity of wearable devices. The reliability of circuit could be influenced by the hole quality of FPC, such as burrs, which is one of the major problem in FPC.

In this paper, micro-drill with a diameter of 0.1 mm was used to drill the double-sided flexible copper clad laminate. The thrust force, the burr and tool wear were investigated. The influencing factors of the height of the burrs were studied. The relationship between the thrust force and the height of the burrs was also explored. Finally, the formation mechanism of burrs was analyzed.

The entrance burrs were usually less than the exit burrs. The burr height increased with the feed per rotation. The height of the burr increased with the increase of the thrust force for the plastic deformation of the copper foil was dominant. The abrasion of the drill gave rise to increase the height of burr. In micro-hole drilling, the growth of burrs can be suppressed effectively by reducing the clearance between the FPC and the backup plate. The thrust force would be controlled in a certain range to reduce the burr with specific drilling parameters. There existed a certain relationship of Gaussian distribution between the height of the burrs and the thrust force of FPC.

The reliability of the integrated circuit was directly affected by the burrs of the FPC. This research on the formation mechanism of FPC burrs and forecast of burr height provided a firm foundation for further work in the area of improvement of the micro-hole quality.

This study aims to examine the impact of board characteristics on firm performance while also exploring the influential mechanisms that help Chinese listed companies establish effective boards of directors and strengthen their corporate governance mechanisms.

This paper uses machine learning methods to investigate the predictive ability of the board of directors' characteristics on firm performance based on the data from Chinese A-share listed companies on the Shanghai and Shenzhen stock exchanges in China during 2008–2021. This study further analyzes board characteristics with relatively strong predictive ability and their predictive models on firm performance.

The results show that nonlinear machine learning methods are more effective than traditional linear models in analyzing the impact of board characteristics on Chinese firm performance. Among the series characteristics of the board of directors, the contribution ratio in prediction from directors compensation, director shareholding ratio, the average age of directors and directors' educational level are significant, and these characteristics have a roughly nonlinear correlation to the prediction of firm performance; the improvement of the predictive ability of board characteristics on firm performance in state-owned enterprises in China performs better than that in private enterprises.

The findings of this study provide valuable suggestions for enriching the theory of board governance, strengthening board construction and optimizing the effectiveness of board governance. Furthermore, these impacts can serve as a valuable reference for board construction and selection, aiding in the rational selection of boards to establish an efficient and high-performing board of directors.

The study findings unequivocally demonstrate the superiority of nonlinear machine learning approaches over traditional linear models in examining the relationship between board characteristics and firm performance in China. Within the suite of board characteristics, director compensation, shareholding ratio, average age and educational level are particularly noteworthy, consistently demonstrating strong, nonlinear associations with firm performance. Within the suite of board characteristics, director compensation, shareholding ratio, average age and educational level are particularly noteworthy, consistently demonstrating strong, nonlinear associations with firm performance. The study reveals that the predictive performance of board attributes is generally more robust for state-owned enterprises in China in comparison to their counterparts in the private sector.

The purpose of this paper is to study the effect of the nano tube fillers on the corrosion protection properties of the self-curing epoxy (SEP) coatings.

The self-curing epoxy (SEP) resin was synthesized via a reaction between diisopropoxy-bis ethylacetoacetato titanate and the epoxy resin. Halloysite nanotubes (HNTs) was surface modified by grafting (3-glycidoxypropyl) trimethoxysilane to obtain modified HNTs (mHNTs). The HNTs and mHNTs are used as nano tube fillers for the SEP coating. The thermal stability of the coatings was assessed via thermo-gravimetric analysis. The field-emission scanning electron microscopy (SEM) was conducted to analyze the surfaces and cross sections of the coatings. The anticorrosive efficiencies of the coatings were investigated by electrochemical measurements and a neutral salt spray test.

The results demonstrated that the additions of HNTs and mHNTs have little effect on the thermal degradation temperature of the SEP coating. However, the addition of the nanotubes reduced the corrosion resistance of the SEP coating.

The SEP coating itself showed excellent corrosion resistance without any reinforcement particles and is hence promising for application in the heavy-duty anticorrosion field of heat exchangers.

Large capacity current carrier printed circuit board (PCB) imposes strict control requirements on the hole wall roughness. The key factors are chip removal, drilling temperature and tool wear. This paper aims to find out a cryogenic drilling process to control the chip removal, chip morphology, tool wear and finally reduce the hole wall roughness.

The chip removal process, chip morphology, tool wear and hole wall roughness of glass fiber epoxy resin copper clad laminate (FR-4) drilling were observed and analyzed. The influence of cold air on the chip removal process, chip morphology, tool wear and hole wall roughness was also investigated. An optimization process of cold air auxiliary drilling was proposed to control the hole wall roughness of FR-4.

The results showed that the discharge time of copper foil chips with obvious characteristics can be used as the evaluation criterion for the smoothness of chip removal. The cold air can promote chip removal and reduce tool wear. In addition, the chip removal and cooling performance will be the best when using −4.7 °C cold air with the injection angle consisted with the angle of helical flute of the drill. The hole wall roughness of FR-4 could be controlled by drilling with −4.7°C cold air.

This paper was the first study of the effect of three kinds of cold air on PCB drilling. This provided a reference for the possibility that the cryogenic drilling methods apply to PCB drilling. A new cold air auxiliary drilling process was developed for large capacity current carrier FR-4 manufacturing.

After over 30 years’ reform and opening-up, China as the second largest economy is now facing the most essential transformation of management philosophy and the biggest challenging issue of business sustainable development, with people’s increasing worry of the deterioration of environmental pollution, food security and human health. It can be said that what China needs urgently today is business ethical value and long-term sustainable development concept, rather than rapidly growing GDP. The purpose of this paper is to assess how the term “sustainable development” is constructed and valued in the sustainability reports or corporate social responsibility (CSR) reports of Chinese corporations, so as to interpret these Chinese firms’ conception of sustainable development in their real business practices.

A corpus of sustainability reports collected from 30 Chinese corporations totaling 247,311 tokens is first of all compiled to realize the objective of study. Then the authors use the AntConc, a corpus analysis toolkit, to generate word lists, key-word-in-context concordances and collocation lists, as well as calculating statistical significance measures for collocates, of which the mutual information (MI) score 3 is most relevant to the paper’s purposes. Based on the key-word-in-context concordance and collocation list, the authors can find what context “sustainable development” usually appears in sustainability reports, thus inferring Chinese corporations’ conception of sustainable development.

The result indicates that Chinese corporations use the rhetoric of weak sustainability, indicating that sustainable development is compatible with further economic growth, which means that Chinese corporations in current China, strongly promoting the concept of new normal economy, still put economic growth as a dominant goal, on which other dimensions of sustainability like environmental protection depend.

The data gleaned in current corpus are limited to the sustainability reports in 2014 thus the study provides no hints as to diachronic trends. However, this study increases our understanding of how Chinese corporations attach value to sustainable development from the view of corpus analysis.

Different from traditional discourse analysis, which usually carries out qualitative analysis to analyze how a word or phrase is constructed in a small number of texts, the authors’ study innovatively introduces the method of corpus analysis to explore how Chinese corporations construct “sustainable development” in their sustainability reports. Thus, the number of texts analyzed is larger in the authors’ study and their findings are more representative and convincing. The authors create a more qualitative understanding of what the reports are actually saying on their reports and prove that corpus methods can bring new application to the discourse analysis of the biggest challenging issue of China’s future economic growth, suggesting a potential novel way to work out the meaning and implication of sustainable development in Chinese real business world.

This study supposes to provide new insights into the role of leader behaviors in motivating employees by examining how and when spiritual leadership and contingent reward leadership facilitate employee vigor at work.

Drawing from self-determination theory (SDT), the current study proposes that spiritual leadership intrinsically motivates employees, whereas contingent reward leadership extrinsically motivates employees – both of which subsequently improve employee vigor at work. The theoretical model was tested through a sample of 191 employees collected across three time points in China.

Results revealed that spiritual leadership positively facilitates employee vigor at work through enhancing their work enjoyment, and employees' need for achievement can amplify the effects of spiritual leadership. In addition, employees' performance-reward expectancy transmits the effects of contingent reward leadership on employee vigor at work, and leaders' performance expectations play a key role in strengthening the positive influences of contingent reward leadership.

Based on SDT, this study provides a comprehensive explanation of how and when two patterns of leader behaviors affect employee vigor at work. Therefore, the authors provide significant insights for leadership and work design in human resource management.