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Remanufacturing of worn blades with various defects normally requires processes such as scanning, regenerating a geometrical reference model, additive manufacturing (AM) through laser cladding, adaptive machining and polishing and quality inspection. Unlike the manufacturing process of a new part, the most difficult problem for remanufacturing such a complex surface part is that the reference model adaptive to the worn part is no longer available or useful. The worn parts may suffer from geometrical deformation, distortion and other defects because of the effects of harsh operating conditions, thereby making their original computer aided design (CAD) models inadequate for the repair process. This paper aims to regenerate the geometric models for the worn parts, which is a key issue for implementing AM to build up the parts and adaptive machining to reform the parts. Unlike straight blades with similar cross sections, the tip geometry of the worn tip of a twist blade needs to be regenerated by a different method.

This paper proposes a surface extension algorithm for the reconstruction of a twist blade tip through the extremum parameterization of a B-spline basis function. Based on the cross sections of the scanned worn blade model, the given control points and knot vectors are firstly reconstructed into a B-spline curve D. After the extremum of each control point is calculated by extremum parameterization of a B-spline basis function, the unknown control points are calculated by substituting the extremum into the curve D. Once all control points are determined, the B-spline surface of the worn blade tip can be regenerated. Finally, the extension algorithm is implemented and validated with several examples.

The proposed algorithm was implemented and verified through the exampled blades. Through the extension algorithm, the tip geometry of the worn tip of a twist blade can be regenerated. This method solved a key problem for the repair of a twist blade tip. It provides an appropriate reference model for repairing worn blade tips through AM to build up the blade tip and adaptive machining/polishing processes to reform the blade geometry.

The extension errors for different repair models are compared and analyzed. The authors found that there are several factors affecting the accuracy of the regenerated model. When the cross-section interval and the extension length are set properly, the restoration accuracy for the blade tip can be improved, which is acceptable for the repairing.

The lack of a reference geometric model for worn blades is a significant problem when implementing blade repair through AM and adaptive machining processes. Because the geometric reference model is unavailable for the repair process, reconstruction of the geometry of a worn blade tip is the first crucial step. The authors proposed a surface extension algorithm for the reconstruction of a twist blade tip. Through the implementation of the proposed algorithm, the blade tip model can be regenerated.

Remanufacturing of worn blades with various defects is highly demeaned for the aerospace enterprises considering sustainable development. Unlike straight blades, repair of twist blades encountered a very difficult problem because the geometric reference model is unavailable for the repair processes. This paper proposed a different method to generate the reference model for the repair of a twist blade tip. With this model, repair of twist blades can be implemented through AM to build up the blade tip and adaptive machining to subtract the extra material.

The authors proposed a surface extension algorithm to reconstruct the geometric model for repair of twist blades.

The purpose of this paper is to present a crack initiation mechanism of the external hydrogen effect on type 304 stainless steel, as well as on fatigue crack propagation in the presence of hydrogen gas.

The effects of external hydrogen on hydrogen-assisted crack initiation in type 304 stainless steel were discussed by performing fatigue crack growth rate and fatigue life tests in 5 MPa argon and hydrogen.

Hydrogen can reduce the incubation period of fatigue crack initiation of smooth fatigue specimens and greatly promote the fatigue crack growth rate during the subsequent fatigue cycle. During the fatigue cycle, hydrogen invades into matrix through the intrusion and extrusion and segregates at the boundaries of α′ martensite and austenite. As the fatigue cycle increased, hydrogen-induced cracks would initiate along the slip bands. The crack initiation progress would greatly accelerate in the presence of hydrogen.

To the best of the authors’ knowledge, this paper is an original work carried out by the authors on the hydrogen environment embrittlement of type 304 stainless steel. The effects of external hydrogen and argon were compared to provide understanding on the hydrogen-assisted crack initiation behaviors during cycle loading.

Due to climate change and an increasing concentration of the world’s population in vulnerable areas, how to manage catastrophe risk efficiently and cover disaster losses fairly is still a universal dilemma.

This paper applies a law and economic approach.

China’s mechanism for managing catastrophic disaster risk is in many ways unique. It emphasizes government responsibilities and works well in many respects, especially in disaster emergency relief. Nonetheless, China’s mechanism which has the vestige of a centrally planned economy needs reform.

I propose a catastrophe insurance market-enhancing framework which marries the merits of both the market and government to manage catastrophe risks. There are three pillars of the framework: (i) sustaining a strong and capable government; (ii) government enhancement of the market, neither supplanting nor retarding it; (iii) legalizing the relationship between government and market to prevent government from undermining well-functioning market operations. A catastrophe insurance market-enhancing framework may provide insights for developing catastrophe insurance in China and other transitional nations.

First, this paper analyzes China’s mechanism for managing catastrophic disaster risks and China’s approach which emphasizes government responsibilities will shed light on solving how to manage catastrophe risk efficiently and cover disaster losses fairly. Second, this paper starts a broader discussion about government stimulation of developing catastrophe insurance and this framework can stimulate attention to solve the universal dilemma.

This paper aims to examine the indirect tax reform process in China. Specifically, it examines the reform of business tax to value-added tax. Inefficiencies within the new tax system are identified and discussed. The “business tax to value-added tax” reform was seen as an essential element in promoting the economic transition and stimulating the service industries (Jin and Jin, 2013).

The paper uses archival and current literature. In undertaking the study, the different periods of indirect tax are examined, prior to 1994, 1994-2012, the changes from 2012 culminating in the new 2017 regime. Attributes of “good” value-added tax (VAT) systems are covered as well as a comparison with New Zealand’s goods and services tax (GST).

The paper finds that to align with the international trend of indirect tax development and more efficiently accomplish the economic transition China needs to build a more neutral VAT system with fewer reduced rates and exemptions and the tax system have created tax inefficiencies and increased the compliance cost. VAT is imposing an increasingly significant impact on China’s national economy and industrial structure as well as accountants.

This is the first study that analyses the indirect tax reforms that are currently being implemented in China and as such has lessons for China but also for VAT/GST in general. We should not forget how special New Zealand’s GST is and the clarity of focus of those who implemented it!

In recent years, the phenomena of “accelerating” and “jumping” during the international expansion of Chinese enterprises have attracted a lot of attention from scholars. However, while a CEO’s career horizon can significantly affect his or her enterprise’s strategic decision-making, few studies have explored the role of CEO career horizon in terms of “accelerating” and “jumping” internationalization.

Based on a sample of China’s A-share listed manufacturing companies from 2008 to 2017, this study explores the impact of CEO career horizon on the internationalization pace and international rhythm of enterprises.

First, the shorter the CEO’s career horizon, the more likely the CEO can avoid risky strategic decisions, which ultimately causes a negative relationship between CEO career horizon and the internationalization pace and rhythm of the enterprise. Second, for larger and older boards of directors, there is a more negative impact of the CEO’s short-term career horizon on the internationalization pace and internationalization rhythm of the company. However, given a larger proportion of female directors and non-executive directors, the CEO’s short-term career horizon has a weaker negative impact on international pace and the rhythm of internationalization.

First, based on upper echelon theory, this study interprets the influence of CEO career horizon on the time dimension of corporate internationalization (including internationalization pace and international rhythm), deepening the theory’s explanatory power. Second, by clarifying the important predictive effect of CEO career horizon on internationalization pace and international rhythm, this research enriches extant research on both variables’ antecedents, as well as that on the influence of CEO career horizon. Finally, by introducing the regulatory role of the board’s supervisory ability, this study clarifies the boundary conditions for the influence of the CEO’s career horizon on international pace and rhythm, and it expands the literature on how CEOs and boards of directors can influence corporate strategic decisions during the internationalization process.

This paper aims to investigate the basin-scale features and mechanisms of the synoptic variation of Yellow Sea Warm Current (YSWC) in winter.

Both in situ current observation and numerical model (MITgcm) were conducted to investigate the synoptic variation of YSWC. The model was well validated and the simulated results were analyzed.

The YSWC shows a much stronger synoptic variation than its mean in winter with strong variation mainly in the deep central YS. The synoptic variation of YSWC is associated a counterclockwise rotary wave as a response to the strong northerly wind bursts. Strong northerly wind generates a large sea surface height (SSH) drop in the Bohai Sea and northern YS. Then, the SSH rotates in a counterclockwise manner. About 18 h later, strong eastward SSH gradient is formed, generating a northward current through geostrophic balance.

The mechanisms analysis shows that the synoptic variation of YSWC is intrinsically linked to SSH as a response to the synoptic varying winter monsoon. This study provides an insight into the spatial and temporal evolution of the oceanic response to strong northerly wind in winter.

Digital libraries and social media are two sources of online information with different characteristics. The purpose of this paper is to integrate self-efficacy into the analysis of the relationship between information sources and decision making, and to explore the effect of self-efficacy on decision making, as well as the interacting effect of self-efficacy and information sources on decision making.

Survey data were collected and the partial least squares structural equation modeling was employed to verify the research model.

The effect of digital library usage for acquiring information on perceived decision quality (PDQ) is larger than that of social media usage for acquiring information on PDQ. Self-efficacy in acquiring information (SEAI) stands out as the key determinant for PDQ. The effect of social media usage for acquiring information on PDQ is positively moderated by SEAI.

Decision making is a fundamental activity for individuals, but human decision making is often subject to biases. The findings of this study provide useful insights into decision quality improvement, highlighting the importance of SEAI in the face of information overload.

This study integrates self-efficacy into the analysis of the relationship between information sources and decision making, presenting a new perspective for decision-making research and practice alike.

To establish a stimulating traffic model of ring road systems and study the traffic effects of ring road in the center of a large city, including the influence in vehicle's travel time and distance.

Different from the ring road systems in the west, Beijing and other big cities in China build ring roads in city center. However, it seems that those systems do not work because the traffic problem still exists when the number of cars in the city increased quickly in past five years. According to the real geographic topology network structure around Er Huan road in Beijing city center, a simplified simulated traffic model was built. Then, two indices of traffic effects, average travel time and path length were studied by comparing the two models with or without ring road.

According to the simulation, although a high‐speed ring road shortens the travel time, it isolates the nature road network system and increases travel distance in the city center. Furthermore, it is uneconomic building a ring road to relieve traffic jams.

Only Er Huan road in Beijing traffic system was simulated in the model. A more complicated ring road system needs to be developed.

A useful model for optimizing traffic system with ring roads, and providing a support for doubting the strategy of developing ring road in city center district in many cities of China.

This is a new way by establishing the simulation model to analyze the scheme of ring road traffic systems. Furthermore, advice for current situation are concluded and it is useful for optimizing current traffic system.

Service providers on highly competitive online outsourcing platforms employ various signals to entice buyers to make online purchases. One such signal—the solution exemplars—attracts attention through depictions of exemplary prior work completed by the service providers. Unfortunately, it is not known the extent to which solution exemplar characteristics affect sales performance nor is it clear how such signals perform in the presence of complementary signals such as service provider expertise. This paper explores these issues.

Extending signaling theory, the authors develop a model to explore the effects of solution exemplar characteristics (i.e. exemplar quantity, exemplar diversity and exemplar popularity) on sales performance under the moderating impact of service provider expertise. The authors test the model using proprietary data from ZBJ.com, a leading online outsourcing platform in China.

Exemplar quantity and exemplar popularity positively affect sales performance; exemplar diversity has no significant impact on sales performance and service provider expertise positively moderates the relationships between exemplar quantity, exemplar popularity and sales performance.

This work makes several significant contributions. First, the authors enrich the research on signals in online outsourcing by exploring the impact of solution exemplar characteristics on sales performance. Second, the authors analyze three solution exemplar characteristics: exemplar quantity, exemplar diversity and exemplar popularity. Third, this work shows that service provider expertise moderates the relationship between solution exemplar characteristics and sales performance. Important practical implications for both online outsourcing platforms and service providers are discussed.

The stock market is vulnerable to various exogenous factors, and its fluctuations can reflect the effects of political, economic and market factors. The purpose of this paper is therefore to choose the stock market as a representative to analyze the potential impact of the Brexit event on global financial markets and how to prevent the spread of risks across global financial markets.

This study chooses the auto-regressive moving average generalized autoregressive conditional heteroscedasticity (ARMA-GARCH) model to fit the financial series and uses it as the marginal distribution model to establish the vine copula model. The maximum spanning tree algorithm is used to select the optimal rattan structure model and pair-copula function. According to the final ARMA-GARCH-R-vine copula model, the tail correlation coefficients of the UK, France, Germany, USA and China stock markets are calculated and used to analyze their dependence structure.

The negative impact of the Brexit event on the British stock market is greater and is more likely to be transmitted to France and Germany. China and the USA are less likely to be impacted by the Brexit incident. The US financial market is more closely linked to France, and it may benefit from the Brexit incident due to the impact of the exchange rate. Although the Chinese stock market is directly connected to the British stock market, due to the existence of national macro-controls and other factors, it will be less affected by the Brexit incident. The main impact comes from the dual devaluation pressure on the RMB.

This paper selects the optimal combination model based on actual data, and the results obtained can accurately reflect the interdependence between relevant stock markets and can guide risk aversion in the financial investment field.