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Viscous dampers are commonly used in large span cable-stayed bridges to mitigate seismic effects and have achieved great success.

However, the nonlinear analysis on damper parameters is usually computational intensive and nonobjective. To address these issues, this paper proposes a simplified method to determine the viscous damper parameters for double-tower cable-stayed bridges. An empirical formula of the equivalent damping ratio of viscous dampers is established through decoupling nonclassical damping structures and linearization of nonlinear viscous dampers. Shaking table tests are conducted to verify the feasibility of the proposed method. Moreover, this simplified method has been proved in long-span cable-stayed bridges.

The feasibility of this method is verified by the simplified model shaking table test. This simplified method for determining the parameters of viscous dampers is verified in cable-stayed bridges with different spans.

This simplified method has been validated in cable-stayed bridges with various spans.

The purpose of this paper is to investigate the superior relationship between blood lipid- and cardiovascular disease (CVD)-related hematological parameters using superior grey relational analysis (GRA).

A total of 294 individuals who underwent simultaneous routine blood examination and blood lipid examination in the Physical Examination Center of the First Affiliated Hospital of Shantou University Medical College were included in this study. Superior GRA was performed to find out the superior factor in CVD-related hematological parameters and blood lipids. CVD-related hematological parameters included red blood cell distribution width, white cell count, and platelet count, platelet distribution width, mean platelet volume, as well as platelet crit. The indicators of blood lipids analyzed here consist of low-density lipoprotein, high-density lipoprotein, triglyceride and total cholesterol.

The results showed that all the grey relational degree of hematological parameters and blood lipids were over 0.8; the superior factor in hematological parameters was PLT, whereas TC was the superior factor in blood lipids.

Findings of this study suggested that hematological parameters are closely related to blood lipids and a potential role for hematological parameters in the prediction of dyslipidemia, which need further study; TC has the greatest influence on hematological parameters, whereas TG displays a minimal impact.

To the authors’ best knowledge, it was the first study to analyze the relationship between various CVD-related hematological parameters and blood lipids via superior GRA.

This paper investigates the policy changes made towards infrastructure public–private partnerships (PPPs). The purpose of this study is to empirically identify the policy risks associated with the development of PPPs and to assess their impacts on the projects.

A case study of the policy changes that have been implemented for PPPs in China over the past seven years has been undertaken and is presented in this study. The causal loop diagrams are applied to assess and illustrate the potential impacts of the risks as a result of such changes on PPPs.

A sequence of the policy risks, which relate to PPP risk allocation, contract management and implementation, payment and abatement mechanisms and financing, has been identified. It is also found that the identified risks will generate significant but negative impacts on PPPs, leading to an ineffective project delivery, low revenue, poor service quality and even contract breach.

This research provides the private-sector entities that will embark on PPPs with an insight into managing and controlling policy risks over the project's lifecycle.

PPPs have been critical for infrastructure development worldwide. Nevertheless, they have been a controversy, as many of them were subjected to poor outputs. Consequently, a variety of political mechanisms has been implemented to enhance the governance for PPPs. Policy can bring not only benefits but also risks and, however, policy risks of PPPs with a particular assessment for their potential impacts have received limited attention. Therefore, the study presented in this paper will contribute to the identification and assessment of policy risks within the context of PPPs.

The purpose of this paper is to examine corporate political activities (CPA) by migrant entrepreneurs to improve business performance in a host developing country.

The authors use a cross‐sectional analysis of 97 Chinese migrant entrepreneurs with business operations in a host developing economy.

A significant positive relationship was found between formal CPAs and performance.

To further deepen the examination of CPAs, new quantification methodologies have to be applied to properly measure CPA relational strength, investment intensity and diversity.

The results enable migrant entrepreneurs to make a more educated decision on the type of CPAs to pursue and to what intensity.

The results could motivate migrant entrepreneurs to adapt rapidly to the host country's formal customs to facilitate socio‐economic adaptation.

This study contributes to literature by examining both formal and informal CPAs, their inter‐relationship and their effects on migrant businesses, which have not been examined previously.

The successful and commercial use of self-driving/driverless/unmanned/automated car will make human life easier. The paper aims to discuss this issue.

This paper reviews the key technology of a self-driving car. In this paper, the four key technologies in self-driving car, namely, car navigation system, path planning, environment perception and car control, are addressed and surveyed. The main research institutions and groups in different countries are summarized. Finally, the debates of self-driving car are discussed and the development trend of self-driving car is predicted.

This paper analyzes the key technology of self-driving car and illuminates the state-of-art of the self-driving car.

The main research contents and key technology have been introduced. The research progress as well as the research institution has been summarized.

This paper examines radical reform of the Chinese public accounting profession in the 1990s. In particular, the paper seeks to provide a more nuanced understanding of the sources, responses and processes of this radical institutional change that effectively paved the way for development of the Chinese accounting profession into the twenty-first century.

The empirical data that inform this study come from both archival materials (mostly in Chinese) and in-depth interviews. These data are analysed and interpreted from a neo-institutionalist perspective, drawing, in particular, on the concept of institutional logics and the concept of institutional work.

A state logic initially guided the development of the Chinese accounting profession but was seriously challenged in the 1990s following a series of high profile financial scandals. The findings reveal a shift to a new professional logic, which was made possible through multiple forms of institutional works instigated by various state actors.

Research into the radical reform of the Chinese public accounting profession in the 1990s was mostly quantitative in nature, focussing mainly on one reform programme, i.e. the disaffiliation of the accounting firms from their sponsoring agencies. This paper adopts a qualitative approach and is aimed at providing a deeper and more nuanced understanding of the institutional change process within its political and economic contexts.

The purpose of this paper is to study the transition process from the crystalline particles appearing before the pump inlet to the stable operation of the pump.

Firstly, a modeling test method was put forward for the high-temperature molten salt pump. Then, according to a modeling test scheme, the experiment of the solid–liquid two-phase flow was carried out by using a model pump similar to the prototype pump. Meanwhile, the numerical method to simulate the transition process of a molten salt pump was studied, and the correctness of the numerical model was verified by the experimental results. Finally, the transition process of the molten salt pump was studied by the verified numerical model in detail.

In the simulation of the transition process, it is more accurate to judge the end of the transition process based on the unchanged particle volume fraction (PVF) at the pump outlet than on the periodic fluctuation of the outlet pressure. The outlet pressure is closely related to the PVF in the pump. The variation of the outlet pressure is slightly prior to that of the PVF at the pump outlet and mainly affected by the PVF in the impeller and volute. After 0.63 s, the PVF at each monitoring point changes periodically, and the time-averaged value does not change with time.

This study is of great significance to further improve the design method of molten salt pump and predict the abrasion characteristic of the pump due to interactions with solid particles.

A numerical method is established to simulate the transition process of a molten salt pump, and a method is proposed to verify the numerical model of two-phase flow by modeling test.

When a reflected shock interacts with the boundary layer in a shock tube, the shock bifurcation occurs near the walls. Although the study of the shock bifurcation has been carried out by many researchers for several decades, little attention has been devoted to investigate the instability pattern of the bifurcation. This research work aims to successfully capture the asymmetry of the whole flow field, and attempt to achieve the instability mechanism of the shock bifurcation by a direct numerical simulation of the reflected shock wave/boundary layer interaction at Ma = 1.9. In addition, the reason for the formation of the bifurcated structure is also explored.

The spatial and temporal evolution of the shock bifurcation is obtained by solving the two-dimensional compressible Navier–Stokes equations using a seventh-order accurate weighted essentially non-oscillatory (WENO) scheme and a three-step Runge–Kutta time advancing approach.

The results show that the formation of shock bifurcation is mainly because of the shock/gradient field interaction, and the height of the bifurcated foot increases with the growth of the shock intensity and the gradient field. The unsteady asymmetry of the upper and bottom shock bifurcated structures is because of the vortex shedding with high frequency in the rear recirculation zone, which leads to the fluctuation of the recirculation area. The vortex shedding process behind the bifurcated structure closely resembles the Karman vortex street formed by the flow around the cylinder. The dimensionless vortex shedding frequency varies between 0.01 and 0.02. In comparison to the scenario at Ma = 1.9, the occurring time of instability is delayed and the upper and bottom bifurcated feet intersect in a relatively short time at Ma = 3.5. The region behind the bifurcated shock is a transitional flow field containing obvious cell structures and “isolated islands.”

This paper discovers an unsteady flow pattern of the shock bifurcation, and the mechanism of this instability in the reflected shock/boundary layer interaction is revealed in detail.

The stability characteristics of an oil film directly influence the safety and service life of mill oil-film bearings. However, very limited work has been done to address the stability characteristics of mill oil-film bearings. To this end, this paper aims to investigate the stability characteristics of mill oil-film bearings through theoretical and experimental analysis.

For the first time, a special designed experiment platform was developed to investigate the stability characteristics of mill oil-film bearings. In addition, a theoretical model of lubricating film of the tested bearings was established to analyze the oil-film stability. The theoretical results were compared with the experimental results.

The comparison results demonstrate that the critical influential factors on the bearing stability were the eccentricity ratio and the ratio of bearing length to diameter. The mill bearing was likely to be unstable under a small load and at a high rotational speed.

The paper includes implications for suitable operation conditions in practical use of mill oil-film bearings.

This paper fulfills an identified need to investigate oil-film stability of mill bearings for practical applications.