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This paper aims to clarify the size and morphology of transition metal dichalcogenides has an impact on lubrication performance of Cu-based composites. This study is intended to show that Cu-based electrical contact materials containing Nb_0.91Ti0.09Se₂ have better electrical and tribological properties than those containing NbSe₂. The tribological properties of Cu-based with different Ti-dopped NbSe₂ content were also discussed.

The NbSe₂ and Nb_0.91Ti_0.09Se₂ particles were fabricated by thermal solid state reaction method. The powder metallurgy technique was used to fabricate composites with varying Nb_0.91Ti_0.09Se₂ mass fraction. The phase composition of Cu-based composites was identified by X-ray diffraction, and the morphology of NbSe₂/Nb_0.91Ti_0.09Se₂ and the worn surface of composites were characterized by scanning electron microscopy and transmission electron microscopy. In addition, the tribological properties of composites were appraised using a ball-on-disk multi-functional tribometer. The data of friction coefficient and resistivity were analyzed and the corresponding conclusion was drawn.

In comparison with the pure copper, Cu-based composites containing Nb_0.91Ti_0.09Se₂/NbSe₂ had a lower friction coefficient, illustrating the Nb_0.91Ti_0.09Se₂ with nano-size particles prepared in this work is a perfect choice for the fabrication of excellent electrical contact composites. Compared to composites with NbSe₂, composites containing Nb_0.91Ti_0.09Se₂ have better tribological and electrical properties.

Because of the use of thermal solid state reaction method, the size of NbSe₂ and Nb_0.91Ti_0.09Se₂ is relatively large. Therefore, the fabrication of finer particles of Nb_0.91Ti_0.09Se₂ is encouraged.

In this paper, the authors discuss the tribological and electrical properties of Cu-based composites, and the value of optimum obtained as Nb_0.91Ti_0.09Se₂ content is 15 Wt.%.

Severe accuracy loss may occur when finite element comes to the distorted mesh model, and the calculation may fail when element mesh degenerates into concave quadrangle or the element boundary is curved. This is a valuable research topic, and many efforts have been made to develop new finite element models. This paper aims to propose two quasi-conforming membrane elements based on the assumed stress quasi-conforming method and fundamental analytical solutions to overcome the difficulties.

First, the fundamental analytical solutions which satisfied both the equilibrium and the compatibility relations of plane stress problem are used as the initial assumed stress of both elements. Then, the stress-function matrices are used as the weighted functions to weaken the strain-displacement equations, which makes only string-net functions on the boundary of the elements are needed in the process of strain integration. Finally, boundary interpolation functions expressed by unknown nodal displacement parameters are adopted to the process of strain integration.

The formulations of both elements are simple and concise, and the elements are immune to the distorted mesh, which can be used to the mesh shape degenerates into a triangle or concave quadrangle and curved-side element. The results of the numerical tests have proven that the new models possess high accuracy.

New formulations of quasi-conforming method are described is detail, and the new strategy exhibits advantages of both analytical and discrete methods.

A higher-order Reissner-Mindlin plate element method is presented based on the framework of assumed stress quasi-conforming method and Hellinger-Reissner variational principle. A novel six-node triangular plate element is proposed by utilizing this method for the static and free vibration analysis of Reissner-Mindlin plates.

First, the initial assumed stress field is derived by using the fundamental analytical solutions which satisfy all governing equations. Then the stress matrix is treated as the weighted function to weaken the strain-displacement equations after the strains are derived by using the constitutive equations. Finally, the arbitrary order Timoshenko beam function is adopted as the string-net functions along each side of the element for strain integration.

The proposed element can pass patch test and is free from shear locking and spurious zero energy modes. Numerical tests show that the element can give high-accurate solutions, good convergence and is a good competitor to other models.

This work gives new formulations to develop high-order Reissner-Mindlin plate element, and the new strategy exhibits advantages of both analytical and discrete methods.

Numerous finite elements are proposed based on analytical solutions. However, it is difficult to find the solutions for complicated governing equations. This paper aims to present a novel formulation in the framework of assumed stress quasi-conforming method for the static and free vibration analysis of anisotropic and symmetric laminated plates.

Firstly, an initial stress approximation ruled by 17 parameters, which satisfies the equilibrium equations is derived to improve the performance of the constructed element. Then the stress matrix is treated as the weighted function to weaken the strain-displacement equations. Finally, the Timoshenko’s laminated composite beam functions are adopted as boundary string-net functions for strain integration.

Several numerical examples are presented to show the performance of the new element, and the results obtained are compared with other available ones. Numerical results have proved that the new element is free from shear locking and possesses high accuracy for the analysis of anisotropic and symmetric laminated plates.

This paper proposes a new QC element for the static and free vibration analysis of anisotropic and symmetric laminated plates. In contrast with the complicated analytical solutions of the equilibrium equations, an initial stress approximation ruled by 17 parameters is adopted here. The Timoshenkos laminated composite beam functions are introduced as boundary string-net functions for strain integration. Numerical results demonstrate the new element is free from shear locking and possesses high accuracy for the analysis of anisotropic and symmetric laminated plates.

Internal audit executives instruct the internal audit department to supervise corporate business management activities, evaluate internal controls and risks and provide recommendations for operating. Therefore, this paper aims to confirm whether and how the supervisory ability of the chief internal audit executive enhances the internal audit department’s function to prevent corporate fraud. Based on the results, this paper further researches the role of the supervisory board position in this relationship.

This paper examines 922 small and medium-sized listed enterprises in China from 2010 to 2017 and empirically investigates the influence of the internal audit executive’s supervisory ability (IAESA) on the occurrence of corporate fraud.

The results reveal that the IAESA is significantly negatively correlated with the occurrence of corporate fraud. This suppression effect is more pronounced when the internal audit executive is also the company’s supervisor. However, if the internal audit executive is the chairman of the board of supervisors, the suppression effect no longer exists. This paper therefore confirms that the IAESA curbs corporate fraud via the improvement of the internal corporate control level.

Because the sample data was limited by the information disclosure level of the included companies, the sample size was relatively small as compared with those of other studies.

This study not only expands the research perspective in the field of internal audit functions but also provides a decision-making reference for the prevention of corporate fraud.

This paper extends an approach that might be able to curb corporate fraud.

A comprehensive index was developed using data envelope analysis to quantify the supervisory ability of internal audit executives. Based on this, this research confirms that the internal audit department performs a “firewall function” to prevent corporate fraud.

The purpose of this paper is to analyze the trading behaviors of retail investors and investigate their impacts on stock returns.

As retail investors are considered as the main noise traders in the capital market, using the trading records of Chinese retail investors from 2005 to 2009, the authors study their trading preferences and the correlation of their trades. Then, they use a multifactor model to test whether the co‐movement of stock returns could be explained by individual sentiment.

The authors' results show that the small‐cap stocks are obviously preferred by retail investors. Meanwhile, the net stock demands of retail investors are systematically correlated, even when the effect of market risk is excluded. In the perspective of the net stock demands, the authors use BSI to measure the individual sentiment, finding that individual sentiment plays an important role in the formation of the cross‐section of stock returns. However, the authors' results imply that BSI is a reverse indicator to predict the future returns, which implies that the trading behaviors of retail investors are irrational.

Consistent with behavioral theory, the authors' findings support the viewpoint that stock returns could be affected by the systematic correlated trading of retail investors. To some extent, their findings highlight the need to know more details of individual investors' trading behaviors through which the fluctuations of asset prices can be better understood.

The purpose of this paper is to assess the application of the nascent corporate opportunity doctrine in China by comparison with its well-established English counterpart; in particular, it evaluates whether the fine balance between business integrity and business efficiency has been struck.

It is argued that the scope of application of the corporate opportunity doctrine in China should be extended, and the rules on the burden of proof should be amended. Moreover, a stricter approach should be adopted by the Chinese judiciary for the purpose of protecting the company’s interests and enhancing business integrity.

This paper mainly focuses on the corporate opportunity doctrine. It does not discuss other duties of directors in detail.

It is useful for directors in balancing business integrity and business efficiency.

It is an original piece of work which assesses the corporate opportunity doctrine by making comparison with English law.

Since their inception in late 2007, the Qualified Domestic Institutional Investor (QDII) funds, which help Chinese investors to invest in foreign capital markets, have experienced significant portfolio losses and persistent fund outflows. While these losses are large in absolute terms, QDII funds, on average, performed better than Chinese A-share funds, but slightly worse than a group of foreign mutual funds. Our study focuses on the QDII industry, and asks three interrelated questions: (1) why have there been large fund outflows from the industry? (2) what explains QDII funds’ poor performance? and (3) why have QDII funds been so heavily exposed to the Hong Kong market? Our empirical analysis shows that the persistent capital outflows were primarily a result of disappointing fund performance. This poor performance can, in turn, be explained by the deficiency of knowledge required of QDII fund managers to successfully invest in foreign capital markets and manage global portfolios. Finally, our study goes some way to explain the phenomenon of QDII funds’ large asset allocation in the Hong Kong market. This ‘Hong Kong bias’ is shown to be consistent with the well-documented ‘home bias’ behaviour in cross-border portfolio investment, but is greatly exacerbated by the lack of global investing experience of QDII managers.

This paper aims to examine the effect of product market competition on firms’ unethical behavior (FUB) in the Chinese insurance industry and to further explore the boundary conditions of the main effects. On the basis of China’s commercial foundation, the study constructs a conceptual framework of FUB by drawing from the perspective of horizontal competition.

Data were collected from 52 property insurance firms at the branch level observed over the six-year period, 2011-2016. Within this framework, market power and market concentration were used to describe product market competition at firm and industry levels, respectively. The moderating effect of market munificence was analyzed to reveal the theoretical boundaries of the main effect. By drawing upon cost–benefit analysis and social network theory, the study used negative binomial model and Poisson model to quantitatively examine the relationship.

The relationship between product market competition and FUB is curvilinear. Especially at the firm level, market power exhibits a U-shape relationship with FUB; at the industry level, market concentration exhibits a U-shape relationship with FUB. In addition, market munificence positively moderates the impact of firm’s market power on FUB, whereas, market munificence negatively moderates the impact of industrial market concentration on FUB.

This paper explored a new type of unethical behavior that concerns consumers or the third party by emphasizing horizontal competitive contexts; it also provides a better understanding of the FUB–financial performance relationship from the perspective of competition. The moderating effects suggest that when the cause of FUB is different (market power vs market concentration), firms may make opposite ethical choice. However, the sample is from a single industry; it will be fruitful to further verify these findings in other industries such as the manufacturing sector. Moreover, the definition of FUB is confined to explicit forms such as participation or collusion but there is no way to measure the implicit forms of FUB.

First, the governance of FUB should not only focus on the firms themselves, but also take into account the industrial market structure. Second, proper use of governance measures for FUB can increase firms’ benefits from “compliance with the law”, enticing firms to decrease FUB. The third, firms with weak market positions, facing fierce competition, should not be involved in FUB for short-term benefit; indeed, a low-cost strategy can be adopted as the dominant competitive strategy. While, in cases of highly concentrated market structure, firms should strive to avoid involvement in FUB through collusion with other rivals.

As it is a very common phenomenon that firms in competitive relationships may adopt FUB toward third parties or consumers, this trend has become a hot topic in the economic and social development in China. The study’s conclusions reveal that a more proactive and ambitious ethical decision is desirable for all kinds of firms; moreover, firms should make a rational choice between “short-term interest” and “long-term survival”. When firms identify the compliance of business ethics as an opportunity to differentiate themselves and perceive the benefits of decreasing FUB as outweighing the costs, the level of FUB will be inhibited, and social welfare will increase.

The primary contribution of this research resides in identifying product market competition as a previously unexplored predictor of FUB, thus revealing the dark side of product market competition. In addition, nonlinear relationships between product market competition and FUB indicate that situations of competition exert an important influence on FUB both at the firm and industry level. This paper’s conclusion provides a more meticulous theoretical explanation for FUB. This research demonstrates that the traditional ethical framework is not sufficient to explain FUB in a horizontal competitive context. Indeed, resource constraints and competitive pressures should also be considered.

Vaccine safety is a major issue in the world. Blockchain technology is the right solution to this worldwide problem. The impact of introducing blockchain technology on the operational efficiency of the vaccine supply chain is unclear. Therefore, from the perspective of game theory, this paper aims to construct a vaccine supply chain model consisting of a vaccine manufacturer, a vaccine traceability service platform based on blockchain technology and a vaccination unit to discuss its pricing and coordination.

This study analyzes the pricing and coordination of the vaccine supply chain based on blockchain technology, compares the decision-making of fixed charge scenario and proportional charge scenario and reveals the impact of blockchain on the vaccine supply chain.

Results demonstrate that the revenue-sharing contract can coordinate the vaccine supply chain when the proportion of revenue sharing meets certain conditions. The fixed charge scenario is more beneficial to the vaccine supply chain than the proportional charge scenario. The introduction of blockchain technology increases the total profit, consumer surplus and social welfare of the vaccine supply chain. Therefore, the operational efficiency of the vaccine supply chain is improved.

This study not only provides important support for enterprises to adopt blockchain technology but also provides some guidance for decision-makers to implement scientific and feasible vaccine supply chain management schemes.