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The paper aims to improve the radiation-proof capability of the self-designed mobile robot with a 7-DOF manipulator, enabling the long-playing inspection and intervention under high-dose radiation environment. In this context, gamma-ray irradiation test for electronic components and specific hardness design have also been specifically presented and discussed.

The study’s hardness design mainly focuses on shielding protection, distance protection and time protection. Irradiation test is first carried out to investigate irradiation resistance of each electronic module. Then, modular deployment and shielding calculation are completed for the point-type nuclear accidents, respectively, to achieve a robust anti-radiation design scheme. Finally, the field experiment is conducted to validate system effectiveness and good mobility, and operational practices are acquired for the realization of time protection.

Coupled with modular redeployment and shielding design, irradiation results illustrate the effectiveness of robotic anti-radiation design. Meanwhile, experiences and reformed measures from the field exercise implement efficient operation and radiological time protection.

Considering the huge risks of high-dose source exposure, the radiation-resistance of the overall system cannot be verified in the field experiment. Fortunately, irradiation test and modular shielding calculation are conducted as a minimal validation.

The proposed anti-radiation design methods and the irradiated results can be applied to many other nuclear vehicles and manipulators for the feasible multi-layer protection and excellent mobility.

A nuclear intervention robot with specific hardness design is presented in detail in this paper. Enlightened by the idea of shielding and distance protection, a large number of electronic modules with multiple types and structures are treated and compared in irradiation experiments, while modular redeployment and retrofitting are completed to reduce irradiated damages. To achieve the effect of time protection, mobility performance and operational practices are discussed and validated in the field experiment based on the mobile system.

During the centennial anniversary of Xinhai Revolution in 2011, the Chinese People’s Political Consultative Conference and the State Administration of Radio, Film, and Television supported the production of 1911 for celebrating such an important event that lead to the rise of the Republic of China in the contemporary Chinese history. This paper aims to reflect upon this film in relation to China’s propagation of “Greater China” for the Empire-building project.

By scrutinizing the film text and following the strait controversies over the film, this paper demonstrates how the Chinese Communist agents employed the coproduction model with Hong Kong for globalizing a cinematic discourse of Greater China in part of their Empire-building project.

The study challenges how contemporary Chinese history is ideologically and politically manipulated for advancing the Chinese Communist propaganda over Taiwan. The overall objective is to reflect upon the longstanding historical divergences that stand on the current geopolitical envision and strategy of China for reunification.

This paper provides an interdisciplinary reflection upon the intricate post-Cold War politics in part of the contemporary Chinese cinema under the China–Hong Kong coproduction model. The findings advance novel and timely insights into China’s current envision and strategy for reunification.

The purpose of this paper is to establish a stiffness model of fixed joint considering self-affinity and elastoplasticity of asperities.

The proposed model considers that asperities of different scales are interrelated rather than independent. For elastoplastic contact, a spring-damper model and an elastic deformation ratio function were proposed to calculate the contact stiffness of asperities.

A revised fractal asperity model was proposed to calculate the contact stiffness of fixed joint, the impacts of the fractal dimension, the fractal roughness parameter and the Meyer index on the contact stiffness were discussed, and the present experimental results and the Jiang’s experimental results showed that the stiffness can be well predicted by proposed model.

The contradiction between the Majumdar and Bhushan model and the Morag and Etsion model can be well explained by considering the interaction among asperities of different scales. For elastoplastic contact, elastic deformation ratio should be considered, and the stiffness of asperities increases first and then decreases with the increasing of interference.

A large-scale detection system with more data in short time bins, small dead space and small signal identification is the ideology the scientists pursuing. These proposed demands are able to be solved by 2.5 D integration. The substance of a 2.5 D integration is called silicon interposer, which consists of the through silicon via (TSV) and redistribution layer. However, the state-of-the-art silicon interposer is not able to sustain its own mechanical strength with the detector/readout array often sitting as standalone in large science facilities and fails to reduce the expansions on the installation of the components due to its insufficient thickness and size. This study aims to propose a moderation of current interposer with large-sized, standalone properties.

This paper proposes an interposer based on double-sided silicon vias (DSSVs) interconnection. Unlike conventional interposer that is interconnected by TSVs, DSSVs interposer is interconnected by top vias (T-vias) and bottom vias (B-vias).

The fabrication process of DSSVs interposer is introduced, and the superiority of the double-sided interconnection process with two etch-stop layers is described in detail. The impact of different T-vias depth on DSSVs interconnections in the same wafer is discussed and two times PI opening processes are proposed to eliminate air bubbles in the B-via. The relationship between the interposer thickness and warpage is studied by finite element analysis simulation and experiment. The prototype of the DSSVs interposer with a size of 100  × 100 mm and a thickness of 318.2 µm is fabricated, and electrical tests including short tests and continuity tests are carried out.

This paper proposes a large-sized and stand-alone interposer based on DSSVs interconnection.

In recent years, the incidence of cardiovascular disease has continued to rise, and early screening and prevention are especially critical. Phonocardiography (PCG) and electrocardiography (ECG), as simple, cost-effective and non-invasive tests, are important tools for clinical analysis. However, it is difficult to fully reflect the complexity of the cardiovascular system using PCG or ECG tests alone. Combining the multimodal signals of PCG and ECG can provide complementary information to improve the detection accuracy. Therefore, the purpose of this paper is to propose a multimodal signal classification method based on continuous wavelet transform and improved ResNet18.

The classification method is based on the ResNet18 backbone, and the ResNet18 network is improved by embedding the global grouped coordinate attention mechanism module and the improved bidirectional feature pyramid network. Firstly, a data acquisition system was built using a MEMS-integrated PCG-ECG sensor to construct a private data set. Second is the time-frequency transformation of PCG and ECG synchronized signals on public and private data sets using continuous wavelet transform. Finally, the time-frequency images are categorized.

The global grouped coordinate attention mechanism and bidirectional feature pyramid network modules proposed in this paper significantly enhance the model’s performance. On public data sets, the method achieves precision, sensitivity, specificity, accuracy and F1 score of 97.96%, 98.51%, 97.58%, 98.08% and 98.23%, respectively, which represent improvements of 3.54%, 3.92%, 4.18%, 4.03% and 3.72% compared to ResNet18. Additionally, it demonstrates a clear advantage over existing mainstream algorithms. On private data sets, the method’s five metrics are 98.15%, 98.76%, 98.08%, 98.42% and 98.45%, further validating the model’s generalization ability.

The method proposed in this paper not only improves the accuracy and efficiency of the test but also provides an effective solution for early screening and prevention of cardiovascular diseases.

Tour guides often use humor to entertain tourists, but the process of tour guide humor (TGH) affecting tourists’ positive word of mouth (PWOM) remains unclear. To fill the gap, this study aims to investigate how TGH enhances tourists’ PWOM through perceived relationship investment, perceived wellness value and trust in tour guides.

A comprehensive mediation model was proposed based on social exchange theory (SET). Data were obtained from 335 tour group tourists and analyzed using structural equation modeling.

Results present that TGH positively predicts tourists’ PWOM. Perceived relationship investment, perceived wellness value and trust in tour guides not only play mediating roles between TGH and tourists’ PWOM, respectively, but also jointly provide two sequential mediation paths (TGH → perceived relationship investment → trust in tour guides → tourists’ PWOM and TGH → perceived wellness value → trust in tour guides → tourists’ PWOM).

The findings have practical value for tour guides and travel agencies to use TGH to improve tourists’ PWOM.

The major contribution is that a reciprocity-based framework rooted in SET was proposed to parse the complex process of TGH promoting tourists’ PWOM. Furthermore, this study enriches current knowledge by confirming that perceived wellness value is not only available in wellness tourism but can be experienced from TGH in mass tourism.

China is currently developing and promoting an industrial cluster policy at the government level. By enacting the ‘Opinion on promoting industrial cluster development’, China is supporting the development of industrial clusters. Building an industrial cluster is done by using a single factor but requires many additional factors like regional characteristics, competitiveness factors are also diversified. To evaluate the competitiveness of the Chinese automobile industry cluster, a competitiveness element index should be developed and a competitiveness evaluation method is needed to evaluate the importance of each element. To accomplish this objective, this research applied the analytic hierarchy process (AHP) and focused on the importance of the competitiveness elements.

This research investigated the character is tics regarding cases of clusters and also analyzed the competitiveness of the Changchun automobile cluster located in northeastern China. The purpose of this research is to help Korean enterprises who enter China in the hopes that Korea will emerge as a top automobile production country.

The purpose of this paper is to analyze the optimal hedging strategy of the oil-stock dependence structure.

The methodology consists to model the data over the daily period spanning from January 02, 2002 to May 19, 2016 by a various copula functions to better modeling the dependence between crude oil market and stock markets, and to use dependence coefficients and conditional variance to calculate optimal portfolio weights and optimal hedge ratios, and to suggest the best hedging strategy for oil-stock portfolio.

The findings show that the Gumbel copula is the best model for modeling the conditional dependence structure of the oil and stock markets in most cases. They also indicate that the best hedging strategy for oil price by stock market varies considerably over time, but this variation depends on both the index introduced and the model used. However, the conditional copula method with skewed student more effective than the other models to minimize the risk of oil-stock portfolio.

This research implication can be valuable for portfolio managers and individual investors who seek to make earnings by diversifying their portfolios. The findings of this study provide evidence of the importance of stock assets for making an optimal portfolio consisting of oil in the case of investments in oil and stock markets. This paper attempts to fill the voids in the literature on volatility among oil prices and stock markets in two important areas. First, it uses copulas to investigate the conditional dependence structure of the oil crude and stock markets in the oil exporting and importing countries. Second, it uses the dependence coefficients and conditional variance to calculate dynamic hedge ratios and risk-minimizing optimal portfolio weights for oil–stock.

The relationship between government and market is the key to the economic development performance of market economy countries. Due to the limits such as the state/market dichotomy, the focus on static allocation efficiency and the ignorance of the diversity of the market economy and the relationship between government and market, economic liberalism and state interventionism can hardly position and explain the role and evolution of government and market in the real world accurately.

China’s economic transition has always adhered to the reform direction of the socialist market economy and the development goal of a modern socialist country as well as the symbiosis and positive and progressive evolution of government and market, blazing a “third way” in handling the relationship between government and market.

The “China’s experience” shows that the key for emerging market economies to achieve good economic development performance lies in whether they can build a new relationship of the mutual integration between and common prosperity of government and market regarding target selection, production organisation, technological innovation, institutional change and regulatory adjustment.

The second part of this paper analyses the inherent defects of economic liberalism and state interventionism as well as the reasons why they can hardly be adopted as the theoretical guidance for emerging market economies to handle the relationship between government and market. The third part analyses how China has transcended the inherent thinking of liberalism and interventionism and shaped the new relationship between government and market through goal-oriented, active and progressive, two-way interactive exploration and practice to ensure the success of China's economic transition.

The paper aims to examine the corporate social responsibility (CSR) activity of audit firms.

Using hand-collected data on all Chinese audit firms’ CSR activities from 2007 to 2020, this study constructs two measures to proxy for audit firms’ CSR engagement: a dummy variable to indicate whether an auditor engages in CSR activities in year t and the frequency with which auditors conduct CSR activities in year t. The authors use ordinary least squares regression as a baseline methodology, along with the entropy balancing method and instrumental variable approach to alleviate potential endogeneity concerns.

The baseline results show that socially responsible audit firms provide higher quality audit services than their counterparts. In particular, the authors find that clients audited by socially responsible audit firms are less likely to receive an aggressively clean opinion. Moreover, the findings suggest that CSR activities related to community and employees are more relevant in improving audit quality compared with those related to other dimensions of CSR. Further analyses show that capital markets and audit clients react positively to audit-firm CSR activity. Audit firms engaging in CSR increase their audit inputs in response to risky clients, as compared with their counterparts. Finally, cross-sectional analyses show that the positive relationship is more pronounced for non-Big 4 and non-industry experts and is attenuated by within-firm geographic dispersion. In terms of client characteristics, the positive effect of audit-firm CSR is stronger when their clients face the higher financial risk or have lower CSR awareness than others. Taken together, these findings are consistent with the ethical view of audit-firm CSR engagement.

The study advances investors’ understanding of audit-firm CSR engagement and helps them evaluate the credibility of audited financial reports. Besides, the findings may also help guide the audit firms to conduct more CSR activities and help guide the audit clients to choose CSR audit firms.

To the best of the authors’ knowledge, this study provides the first large-sample evidence by empirically examining the association between audit-firm CSR activity and audit service performance. Besides, this paper also explores audit-firm CSR activity from two competing perspectives, thereby providing a comprehensive understanding of this issue. Finally, this work responds to the call for more CSR research in emerging markets.