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The purpose of this paper is to introduce a new copper electroplating formula which is able to fill blind microvias (BVHs) and through holes (THs) at one process through a direct current (DC) plating method.

Test boards of printed circuit board (PCB) fragments with BVHs and THs for filling plating are designed. The filling plating is conducted in a DC plating device, and the filling processes and influence factors on filling effect of BVHs and THs are investigated. Dimple depths, surface copper thickness, thermal shock and thermal cycle test are applied to characterize filling effect and reliability. In addition, to overcome thickness, increase of copper on board surface during filling plating of BVHs and THs, a simple process called pattern plating, is put forwarded; a four-layered PCB with surface copper thickness less than 12 μm is successfully produced.

The filling plating with the new copper electroplating formula is potential to replace the conventional filling process of BVHs and THs of PCB and, most importantly, the problem of thickness increase of copper on board surface after filling process is overcome if a pattern plating process is applied.

The dimple depth of BVHs and THs after filling plating is not small enough, though it meets the requirements, and the smallest diameter and largest depth of holes studied are 75 and 200 μm, respectively. Hence, the possibility for filling holes of much more small in diameter and large in depth with the plating formula should be further studied.

The paper introduces a new copper electroplating formula which achieves BVHs and THs filling at one process through a DC plating method. It overall reduces production processes and improved reliability of products resulting in production cost saving and production efficiency improvement.

Ball bearings in gas turbine have played a critical role in supporting heavy radial loads but with higher failure rates and repair costs. Therefore, the purpose of this study is to introduce and study a method for their failure analysis with an actual industrial example to guarantee operation reliability and safety.

Spectrometric oil analysis was used as an early abnormal wear indicator, based on which emergent in-use oil replacement was carried out to reduce the wear rate. However, with wear deterioration, further wear failure investigation was conducted by LaserNet Fines and ferrography to detect the imminent wear failure. Finally, with the assistance of elemental analysis of the typical wear particles, the root cause and worn components were determined by scanning electronic microscope and energy-dispersive X-ray spectroscopy.

The results have shown that an extraneous source led to wear failure, which later caused overheat between the outer bearing ring and ball. It is in accordance with visual inspection of the disassembled engine.

This method has specified the occasion under which the suitable measurement can be taken. It can achieve the rapid wear condition assessment allowing for root cause and worn parts identification. In addition, wear rate reduction by change of oil can be efficient for most of the time to avoid premature disassemble, especially with the possibility of contamination. It has provided experience to address similar industry-level practical wear failure analysis problems.

This study investigates whether corporate executives, who are university alumni, influence each other's firm corporate social responsibility (CSR) performance.

Drawing on social network theory, the authors hypothesise that a firm's CSR performance is positively associated with its peer firms' average CSR performance when the executives of the firm and its peer firms are university alumni. The study employs data from 1,685 listed firms and 4,906 executives who graduated from 585 different universities in China and runs multivariate regressions.

The results reveal a sizeable university peer influence on CSR performance. Such influence is even stronger for executives who graduated from elite universities (e.g. 985 or 211 universities), and universities or programmes that provide more opportunities for alumni reunions or networking (e.g. MBAs/EMBAs). Executives who are more influential in making firm decisions (e.g. CEOs/CFOs), as well as firms that are more likely to mimic the behaviour of others, also show higher degrees of university peer influence.

The results highlight the role of education in ethical decision-making.

This study documents evidence on a new determinant of firm CSR performance. The study sheds light on the impact of non-institutionalised personal ties, for example, university alumni networks, on CSR performance.

The purpose of this study is to examine the relationship between the corporate social responsibility (CSR) performance of job-hopping executives at their former and subsequent firms.

We conduct regression analyses using a sample of firms listed on the Shanghai and Shenzhen Stock Exchanges from 2010 to 2020 to examine whether CSR performance is similar from one firm to the next as executives switch jobs.

We find a positive relationship between the CSR performance of former and subsequent firms under job-hopping executives. This relationship is the strongest in the year of the job switch; it weakens in the second year and eventually disappears in the third year. In addition, we show that this relationship benefits different CSR stakeholder groups and is contingent on executive and subsequent firm attributes and job-hopping characteristics. Furthermore, we demonstrate that firms that hire a new chief executive officer from a firm with a strong track record in CSR, the new firm experiences a significant surge in CSR performance compared with firms that do not experience such a shock.

This study has implications for executive hiring decisions.

This study extends the understanding of CSR determinants through the lens of inter-organisational ties associated with job-hopping executives.

This paper aims to explore whether drivers would adapt their behavior when they drive among automated vehicles (AVs) compared to driving among manually driven vehicles (MVs).Understanding behavioral adaptation of drivers when they encounter AVs is crucial for assessing impacts of AVs in mixed-traffic situations. Here, mixed-traffic situations refer to situations where AVs share the roads with existing nonautomated vehicles such as conventional MVs.

A driving simulator study is designed to explore whether such behavioral adaptations exist. Two different driving scenarios were explored on a three-lane highway: driving on the main highway and merging from an on-ramp. For this study, 18 research participants were recruited.

Behavioral adaptation can be observed in terms of car-following speed, car-following time gap, number of lane change and overall driving speed. The adaptations are dependent on the driving scenario and whether the surrounding traffic was AVs or MVs. Although significant differences in behavior were found in more than 90% of the research participants, they adapted their behavior differently, and thus, magnitude of the behavioral adaptation remains unclear.

The observed behavioral adaptations in this paper were dependent on the driving scenario rather than the time gap between surrounding vehicles. This finding differs from previous studies, which have shown that drivers tend to adapt their behaviors with respect to the surrounding vehicles. Furthermore, the surrounding vehicles in this study are more “free flow'” compared to previous studies with a fixed formation such as platoons. Nevertheless, long-term observations are required to further support this claim.

This study aims to investigate the influences of two facets of Vietnamese consumers' cultural identities (i.e. global and national) on their intent to consume Korean lifestyle products and services via attitudes toward Korea. The difference between generations (Generation Z vs. X) is examined.

Data are collected through an online survey firm. The participants are Vietnamese consumers residing in Vietnam, varying in age from teens to those in their 50s (n = 500). The collected data are analyzed by SPSS 21.0 for the descriptive statistics, frequency analysis, and reliability analysis. AMOS 21.0 is employed for confirmatory factor analysis and structural equation modeling (SEM) analysis.

This study reveals that global identity affects Vietnamese consumers' attitudes toward Korea and their intent to consume Korean lifestyle products and services. Results show that only global identity affects attitudes and behavioral intention toward Korea among generation Xers, while national identity has no effect. For Generation Z (Gen Z), both global and national identities have a positive effect on attitudes toward Korea, which also increases the intent to consume Korean lifestyle products and services.

Measuring individuals' global and national identities will allow brands and retailers to better understand international consumers of various generations and develop global marketing strategies.

This study bridges gaps in the literature on globalized consumption in a non-Western context by identifying how consumers in emerging markets become involved in cross-cultural consumption.

This study aimed to investigate the influence of brand-targeted animosity on consumers' boycott intentions for target fashion products via their cognitive and affective evaluations, in the context of the “Xinjiang cotton ban” incident. The moderating role of xenocentrism was also examined.

Data were collected through an online survey in China using convenience sampling, and 411 valid responses were obtained. The collected data were analyzed using SPSS 26.0 for the descriptive statistics, frequency analysis and reliability analysis. AMOS 24.0 was employed for the confirmatory factor and structural equation modeling analyses. Bootstrapping analysis using PROCESS Macro was employed to analyze the moderating effects.

This study found that consumers' brand animosity directly and positively affected boycott intentions and that this influence was sequentially mediated through cognitive-affective evaluations. However, cognitive product judgment did not directly affect boycott intentions. The results showed that xenocentrism had a moderating effect on the relationship between animosity and cognitive judgment. The higher the xenocentrism of consumers, the weaker the negative effect of animosity was on cognitive judgment.

This study bridges the gap in the literature on animosity and xenocentrism in a fashion-related context through examining the consequences of brand animosity.

Fabrics with photothermal conversion functions were developed based on the introduction of shape stable composite phase change materials (CPCMs).

Acidified single-walled carbon nanotubes (SWCNTs) were selected as support material to prepare CPCMs with n-octadecane to improve the thermal conductivity and shape stability. The CPCMs were finished onto the surface of cotton fabric through the coating and screen-printing method. The chemical properties of CPCMs were characterized by Fourier transform infrared spectrometer, XRD and differential scanning calorimetry (DSC). The shape stability and thermal conductivity were also evaluated. In addition, the photothermal conversion and temperature-regulating performance of the finished fabrics were analyzed.

When the addition amount of acidified SWCNTs are 14% to the mass of n-octadecane, the best shape stability of CPCMs is obtained. DSC analysis shows that the latent heat energy storage of CPCMs is as high as 183.1 J/g. The thermal conductivity is increased by 84.4% compared with that of n-octadecane. The temperature-regulating fabrics coated with CPCMs have good photothermal conversion properties.

CPCMs with high latent heat properties are applied to the fabric surface through screen printing technology, which not only gives the fabric the photothermal conversion performance but also reflects the design of personalized patterns.

CPCMs and polydimethylsiloxane (PDMS) are mixed to make printing paste and printed cotton fabric with temperature-regulating functional is developed.

SWCNTs and n-octadecane are composited to prepare CPCMs with excellent thermal properties, which can be mixed with PDMS to make printing paste without adding other pastes. The fabric is screen-printed to obtain a personalized pattern and can be given a thermoregulatory function.

This paper aims to investigate the economic consequence of the tax reductive strategy on stock price. The authors’ theory, empirically reinforced, suggests managerial tax aggressiveness endangers the corporation through a heightened risk in stock price crashing. Information opacity worsens the situation by reinforcing the relationship. Policymakers should emphasize two aspects: market openness and tighter institutional monitoring. The evidence shown in this paper demonstrates that these two weaken the tax aggressiveness impact on risk of a crashing stock price.

The sample in this paper consists of 9,702 observations from listed firms from 2008 to 2013 in China. The tax rate is manually collected and all the other original data used in this study are sourced from Wind and China Capital Market and Accounting Research databases. Both logistic regression and ordinary least squares regression methods are used to test the hypothesis in this paper.

One key insight is in tax aggressiveness to be strongly correlated with a greater risk of future stock price crashing. The authors also found information opacity to exert a positive moderating effect. That is, the higher the information opacity, the stronger and more positive the correlation between tax aggression and stock price crash risk. However, the market process and an institutional investor have opposite, negative impacts. An open market environment reduces their correlativeness. Similarly, stronger institutional vigilance leads to an attenuation of such a co-relationship.

The findings of this paper have wide policy implications for management and control by authorities of listed corporations. Aggressiveness in management of corporate taxes accentuates the risks borne by stockholders. If so, internally within the corporation, such aggression shown by management, if not proscribed, could be subject to scrutiny, possibly by an independent committee. Externally, this may be countered by the authority in emphasizing three key factors: openness in information sharing, the market environment and tighter institutional monitoring.

This study provides a consequential theory of aggressive management of tax, rigorously analyzed and strongly, empirically supported. Overall, aggressiveness in tax management is related with assumption of higher risks in the crashing of stock price. The relationship is enhanced through information opacity, but reduced via market environment and institutional monitoring.

The purpose of this paper is to present a new method to optimize the micro drill bit based on finite element analysis, and analyze the performance of the asymmetric helix groove micro drill bit and provide a way to conduct the optimization of micro drill bits.

First, the stress and deform of the micro drills were analyzed in ANSYS. Second, the influence of helix angle, web thickness and ratio of flute to land on stiffness was explored. Combining the former two results, a better set of parameters were optimized. Third, the modal analysis and harmonic response analysis of the optimized micro drill bit were analyzed in ANSYS. Finally, an experiment was carried out to verify the performance of the asymmetric helix groove micro drill bit.

The stress and deform of the asymmetric helix groove micro drill bit are not symmetric. The rigidity is getting better with the web thickness increasing in the selected range; while, the rigidity is getting worse with the helix angle and ratio of flute to land increasing in the selected range. The natural frequencies of the optimized micro drill bit are far away from the excitation frequency, and the response displacement is very small under the excitation of the spindle. In the drilling experiment, the optimized micro drill bit performs well.

In this paper, the diameter of the asymmetric helix groove micro drill bit was 0.3 mm and the cross-section shape was not considered. The future research work should consider different diameters and cross-section shapes.

Analyzing the influence of three main geometry parameters on the rigidity in ANSYS, a better set of parameters were optimized from the analysis results. The drilling experimental results show that this method is of great significance for obtaining the appropriate parameters of asymmetric helix groove micro drill bits.