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The purpose of this paper is to construct a frequency-domain framework to study the asymmetric spillover effects of international economic policy uncertainty on China’s stock market industry indexes.

This paper follows the time domain spillover model, asymmetric spillover model and frequency domain spillover model, which not only studies the degree of spillover in time domain but also studies the persistence of spillover effect in frequency domain.

It is found that China’s economic policy uncertainty plays a dominant role in the spillover effect on the stock market, while the global and US economic policy uncertainty is relatively weak. By decomposing realized volatility into quantified asymmetric risks of “good” volatility and “bad” volatility, it is concluded that economic policy uncertainty has a greater impact on stock downside risk than upside risk. For different time periods, the sensitivity of long-term and short-term spillover economic policy impact is different. Among them, asymmetric high-frequency spillover in the stock market is more easily observed, which provides certain reference significance for the stability of the financial market.

The originality aims at extending the traditional research paradigm of “time domain” to the research perspective of “frequency domain.” This study uses the more advanced models to analyze various factors from the static and dynamic levels, with a view to obtain reliable and robust research conclusions.

Boundary decision is an important but underexplored theme in digital platform research. The boundary decision of digital platform enterprises (DPEs) differs from traditional organizations because of cross-side network effects (CNEs). This study intends to investigate whether transaction cost economics (TCE) and resource-based view (RBV), as classical organization boundary mechanisms, are still applicable for DPEs.

To unfold the research problem, this study conducts a fuzzy-set qualitative comparative analysis (fsQCA) on the samples of 21 platform business units.

The results show that the classical boundary decision theory still applies in the context of DPEs, but the cross-side network effects will affect boundary decision of DPEs.

This study provides a new framework – integrates TCE, RBV and CNEs – to analyze boundary decision of DPEs. This paper also contributes to research on both organization boundary decision and platform governance.

In this paper, the mechanical properties and corrosion resistance of CoCr alloy fabricated by selective laser melting (SLM) were studied, and the changes of performance after porcelain sintering process were also analysed. This study is to point out the relationship between the microstructure, mechanical properties and corrosion resistance of CoCr alloys prepared by SLM after porcelain sintering process. In addition, the biosafety of the sintered CoCr alloy was evaluated.

The microscopic feature changes of CoCr alloy samples after porcelain sintering process were observed by DMI 5000 M inverted metallographic microscope and Nova Nano430 FE-SEM. Moreover, phase identification and determination were conducted by X-ray diffraction (XRD) using Smartlab X-ray diffractometer. The Vickers microhardness was measured on the HVS-30 microhardness tester, and tensile tests were carried out on a CM3505 electronic universal testing machine. The corrosion resistance was tested by a classical three-point electrode system electrochemical method, then the ion precipitation was measured by using an atomic absorption spectrometer of Z2000 7JQ8024.

The XRD results indicate that the transition of γ phase (FCC) to e phase (HCP) occurs during the porcelain sintering processing of CoCr alloy. Moreover, the Vickers microhardness of the upper surface and the side surface of the CoCr alloy sample was improved by more than 36%. In addition, the ultimate strength of CoCr alloy via porcelain sintering treatment was increase to 1,395.3 ± 53.0 MPa compared to 1,282.7 ± 10.1 MPa of unprocessed CoCr alloy. However, the corrosion resistance of CoCr alloy samples decreases after porcelain sintering process.

There are few studies on the relationship of microstructure, mechanical properties and corrosion resistance of CoCr alloys prepared by SLM after porcelain sintering process. In this study, the microstructure, mechanical properties and corrosion resistance of CoCr alloy after porcelain sintering process were studied, and the biosafety of the alloy was evaluated. The research found that it is feasible to apply CoCr alloy fabricated by SLM to dental medicine after porcelain sintering process.

Workplace safety has been a persistent issue for safety-critical organizations. Based on self-verification theory, this study investigates how authentic leadership affects safety behaviors in a collectivistic context.

This research collected 259 matching questionnaires for high-speed railway (HSR) drivers and their supervisors in China. Specifically, HSR drivers were invited to fill in their general perceived authentic leadership, person-organization fit and collectivistic orientation. In addition, their direct supervisors were invited to assess their safety behaviors.

Authentic leadership exhibits a significant positive impact on safety compliance and safety participation, implying that authentic leadership positively impacts safety behavior. The person-organization fit partially mediated the relationship between authentic leadership and safety behavior (safety compliance and participation). Furthermore, collectivistic orientation moderates the relationship between authentic leadership and person-organization fit.

The findings of this study provide important insights into authentic leadership and person-organization fit for developing effective strategies to improve workplace safety.

Smooth appearance of fabrics after ironing with steam, soleplate, ironing speed and their interactions cannot be studied using household ironing machines such as hang steamer and flatiron. The purpose of this paper is to present the design and verification of a simple, low-cost test platform based on the fabric materials hang-ironing factors includes temperature, humidity, ironing speed (time).

This platform achieves adjustable and stable steam flow rate, enabling any ironing speed and any temperature of soleplate below 200°C. Moreover, the whole ironing process is automatically after experiment level set ahead for better observation to the ironing process.

Regression results of the apparatus are stable, statistical significant which is verified by the statistics under design of experiment.

It is useful in other aspects such as nozzle test and improvement, new products evaluation and smooth appearance level experiment and test for new ironing product and its research. It is also useful in other aspects such as nozzle test and improvement, new products evaluation and smooth appearance level experiment and test for new ironing product and its research.