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This study aims to examine the transmission mechanism of factors on the characteristic fluctuation of Vietnamese coffee bean export price (PVN).

Applying Markov switching–vector autoregressive model.

Significantly, the empirical results showed that the transmission of independent variables on PVN is non-linear, and the fluctuation of PVN is affected by many factors, especially PVN in the previous period. In addition, the effect of Robusta coffee price was the greatest with coefficient is 0.28785, and the correlation between PVN and it was also the highest in both regimes with coefficients are 0.5317 and 0.3959, respectively.

These obtained results are in accordance with reality, as Vietnam is the largest exporter of Robusta coffee in the world.

The purpose of this paper is to evaluate the influence of VND/USD exchange rate on Vietnamese coffee export price (PVN).

The study uses cointegration test, Granger causality test and vector autoregression (VAR) model.

The results reveal that there is no co-integrating equation between two variables. It means the exchange rate does not have an effect on PVN in the long run. Furthermore, there is one Granger causality relationship between VND/USD exchange rate and PVN in the short run, but not vice versa. The study suggests that the first previous period of PVN is the most closely related variable which has the greatest impact on the variation of PVN among the selected variables, meanwhile the effect of VND/USD exchange rate on it, contrarily, is positive and very trivial.

In overall, the impact of VND/USD exchange rate on Vietnamese coffee export price (PVN) has been analyzed deeply in this research by applying new approaches.

This paper aims to study the impact of transient velocity changes on sealing performance during reciprocating sealing processes.

Establish a model of transient mixed lubrication, solve the transient Reynolds equation, consider the effect of temperature rise at the seal interfaces, and determine the behavior of the seal interfaces, such as film thickness and fluid pressure. Evaluation with friction and leakage rate, calculate the variation of sealing performance with reciprocating velocity under different working conditions, and verify it through bench experiments.

Within a reciprocating stroke, the frictional force decreases with increasing velocity, and the frictional force of the outstroke is greater than that of the instroke; at the time of the stroke transition, the fluid pressure is smallest and the rough peak contact pressure is greatest. At present, the dynamic pressure effect of fluids is the largest, and the friction force also increases, which increases the risk of material wear and failure. Friction and leakage increase with increasing pressure and root mean square roughness. As temperature increases, friction increases and leakage decreases. In studying the performance variations of seal components through a reciprocating sealing experiment, it was found that the friction force decreases with increasing velocity, which is consistent with the calculated results and more similar to the calculated results considering the temperature rise.

This study provides a reference for the study of transient sealing performance.

The color TV industry in China has become a mature industry. Its development demonstrates and provides reference implications for how developing industries within a country can achieve a technological leap. This paper aims to address this issue.

An exploratory case study approach is taken to find the key factors in the technological catch‐up of China's traditional industry.

In the study it is found that China's color TV industry, as a mature traditional industry, has four‐dimensional key factors affecting the catch‐up of technology in the flat‐panel stage: market; merger and acquisition; international cooperation innovation for patent; and the roles of internal reform. “Market” is the window of opportunity and challenge; “merger and acquisition” is the key factor for making the patent convert from external mode to internal mode by deviant‐track. The “international cooperation innovation for patent” is also a key factor to ensure achievement of technology catch‐up and sustainable technological innovation. The role of internal reform promoter is the key factor in the technological catch‐up process in which taking entrepreneur as the core.

The article describes Changhong's flat‐panel TV technology catch‐up mode, analyzes four‐dimensional key factors affecting the technology catch‐up of China's color TV industry; the Chinese color TV industry as mature industry; and discusses which developments have demonstrated how to achieve a technological leap in developing industries.

The purpose of this paper is to empirically analyze the motive of family‐controlled firms to pay cash dividends in China.

Using some econometrical models, the paper designs and conducts a series of empirical research on cash dividends behavior, thus acquiring credible empirical data.

Using a sample of 204 family firms, the motive of family‐controlled firms to pay cash dividends was investigated. Dividend ratio was found to decrease with the separation of ultimate ownership and control right; this may reflect the tunneling motive of the family owners. Different from others, it was also found that high‐growth firms pay more dividends and that the family doing so may want to build a high reputation for the friendly treatment of minority investors for future financing.

The paper discusses investor protection matters in China.

The paper' findings provide policy implications for corporate governance reform and capital market development in China.

Empirical publications on the time series modeling and forecasting of electricity prices vary widely regarding the conditions, and the findings make it difficult to generalize results. Against this background, it is surprising that there is a lack of statistics-based literature reviews on the forecasting performance when comparing different models. The purpose of the present study is to fill this gap.

The authors conduct a comprehensive literature analysis from 2000 to 2015, covering 86 empirical studies on the time series modeling and forecasting of electricity spot prices. Various statistics are presented to characterize the empirical literature on electricity spot price modeling, and the forecasting performance of several model types and modifications is analyzed. The key issue of this study is to offer a comparison between different model types and modeling conditions regarding their forecasting performance, which is referred to as a quasi-meta-analysis, i.e. the analysis of analyses to achieve more general findings independent of the circumstances of single studies.

The authors find evidence that generalized autoregressive conditional heteroscedasticity models outperform their autoregressive–moving-average counterparts and that the consideration of explanatory variables improves forecasts.

To the best knowledge of the authors, this paper is the first to apply the methodology of meta-analyses in a literature review of the empirical forecasting literature on electricity spot markets.

Although proximal row carpectomy, wrist arthrodesis and even total wrist arthroplasty were developed to treat wrist disease using bone and cartilage of the wrist, severe and complicated bone defects caused by ferocious trauma and bone tumors remain a stubborn problem for surgeons. Development and application of the three-dimensional (3D) printing technology may provide possible solutions.

Computed tomography (CT) data of three cases with severe bone defects caused by either trauma or bone tumor were collected and converted into three-dimensional models. Prostheses were designed individually according to the residual anatomical structure of the wrist based on the models. Both the models and prostheses were produced using 3D printing technology. A preoperative design was prepared according to the models and prostheses. Then arthroplasty was performed after preoperative simulation with printed models and prostheses.

The diameter of the stem and radial medullary cavity, the direction and location of the prosthesis, and other components were checked during the preoperative design and simulation process phases. The three cases with 3D printed wrist all regained reconstruction of normal anatomy and part of the function after surgery. The average increasing Cooney score rate of Cases 2 and 3 was 133.34 ± 23.57 per cent, and that of Case 1 reached 85 per cent. The average declining rate of the Gartland and Werley Score in Cases 2 and 3 was 65.21 ± 18.89 per cent, and that of Case 1 dropped to 5 per cent in the last follow-up. The scores indicated that patients experienced pain relief and function regain. In addition, the degree of patient satisfaction improved.

3D printed wrist arthroplasty may provide an effective method for severe and complicated cases without sacrificing other bones. Personal customization can offer better anatomy and function than arthrodesis or other traditional surgical techniques.