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The paper aims to use aluminium alloy to substitute steel as the main material of ultra-precision hydro-static bearing system for an ultra-precision plastic electronics production system to lower the manufacturing cost. The total cost of diamond turning and nickel-based electroless coating of an aluminium alloy bearing is expected to be less than the cost of manufacturing a stainless steel bearing.

The paper used a large amount of theoretical calculation to obtain optimal specifications of the bearing system. ANSYS modelling was selected to simulate the deflection of the bearing shaft under high oil pressure. Hundreds of measurements were conducted after the bearing had been manufactured.

The paper provides industrial application insights on using aluminium alloy with a high-quality nickle-based electroless coating as a successful substitution of stainless steel. This created a more economic hydro-static bearing system.

Because of the time limit, different rotational speed tests shall be conducted in the future.

The paper provides implications for the application of nickel-based electroless coating to improve the surface property and bending strength of aluminium alloy, as well as classifying ultra-precision diamond turning as an economic finishing process.

This paper has identified the importance of aluminium alloy with a nickel-based electroless coating as the substitution of stainless steel in a precision hydro-static bearing system.

The serious friction and wear problem occurs on the mechanical seal’s faces during the start-up stage of the high-speed turbopump for a liquid rocket engine. This paper aims to propose a kind of thick metal alloy coatings on the surface of the seal’s rotor so as reduce the friction and wear.

With the pin-disk (the graphite pin and the disk with the metal coating) tribology-tester, the tribological behaviors of four metal coatings are investigated. The special friction coefficients under the dry friction, boundary friction and different temperatures of water-lubricated conditions were obtained.

The test results show that the thick metal coating has a good performance of the wear resistance and friction reduction; and the friction coefficients of a Sn-Sb-Cu coating under the dry friction and water-lubricated conditions are 0.377 and 0.043, respectively, and the corresponding mass wear volumes are only 2.74 and 0.81 mg, respectively.

The thick metal coating scheme for the mechanical seal’s faces might lend itself to the harsh working conditions of the low-viscosity liquid rocket engine.

The paper attempts to discuss the optimal pricing decisions under the decentralized and centralized decision and analyze the influence of online reviews and in-sale service on dual-channel supply chain. Finally, the authors design a two-part tariff coordination mechanism.

To deal with this pricing conflict problems of dual-channel supply chain consisting of dominant manufacturer and a retailer, considering the fact that online reviews and in-sale service are important factors on consumers’ purchase decisions, the authors establish some basic models and exploit them to discuss the optimal pricing decisions under the decentralized and centralized decision and analyze the influence of online reviews and in-sale service on dual-channel supply chain. Finally, the authors design a profit-sharing coordination mechanism.

The results show that the optimal online direct selling price is positively correlated with product perceived quality obtained from online reviews and negatively correlated with the in-sale service. The traditional retail price is positively correlated with the in-sale service and weakly correlated with online reviews. For the manufacturer and retailer, whether decentralized decision or coordination contract, their profits increase with the increase of the in-sale service in a certain range and quality perceived from spontaneous online reviews. Online reviews and in-sale service are important factors on consumers’ purchase decisions. Positive in-sale services and online reviews can provide consumers with a better shopping experience, thereby promoting their enthusiasm for shopping and improving their quality of life. The two-part tariff coordination mechanism improves the profits of the manufacturer and the traditional retailer, respectively, through the transfer fee.

The proposed approach can well analyze the channel conflicts and pricing problems between retailers and manufacturers with respect to product offline price and online price. The analysis and results can inform decision-making for manufacturers and retailers.

The political influence on the determinants of capital structure has been under-researched for a long time. Taking the turnover of secretary of municipal committee as a political factor in China, this paper studies the effect of local government officials' turnover on firm's capital structure.

Starting with all A-shares listed firms in the Shanghai and Shenzhen Stock Exchanges from 2001 to 2018, this paper implements the OLS estimation, staggered difference-in-difference approach to investigate the effects of political turnover on the choice of capital structure.

The results show that, driven by government officials' turnover, firms will significantly reduce their leverage. When comparing between formal finance (bank loans) and informal finance (payables), the reduction of capital structure is mainly driven by banks, not by suppliers. Furthermore, two possible channels have been investigated. First, the reduction effects are mainly driven by the SOEs when classifying the types of corporate ownership into SOEs and non-SOEs. Second, the reduction effects exist in areas with the more intense government intervention when considering the heterogeneity of the development of institutional environment in provinces.

This paper first contributes to the literature on the determinants of corporate choice on capital structure. Second, this paper enriches the studies on the economic consequences of local government officials' turnover.

The findings suggest that reducing information processing costs as a result of better transportation is an important ingredient in promoting the pricing of firm-specific information. This study aims to discuss the aforementioned issue.

The authors adopt a difference-in-difference (DID) research design to examine the impact of information processing costs on stock price synchronicity with a sample of firms listed in the Chinese A-share market during 2007 and 2017.

This paper shows that the launch of the high-speed railway (hereafter HSR) in China is associated with lower stock price synchronicity, consistent with the theory that the HSR reduces investors’ information processing costs (cost of monitoring, acquiring and analyzing firm disclosures). This effect is more pronounced for companies located in remote areas than for those located in large cities. Further tests show that the negative association between the launch of HSR and stock price synchronicity is stronger for companies with higher information asymmetries, proxied by higher equity concentration, higher complexity and lower internal control quality.

This study contributes to the literature in the following three ways. First, prior literature relates the effects of geographic distance to information transmission and information asymmetry between insiders and outside investors (e.g. Coval and Moskowitz, 2001; Kang and Kim, 2008; Malloy, 2005). The authors supplement the literature by providing new empirical evidence from an exogenous shock (natural experiment), that is, the launch of HSR, that facilitates transportation and reduces information transmission costs. Second, prior studies have shown that new airline routes that facilitate transportation improve investment and productivity (e.g. Bernstein et al., 2016; Giroud, 2013). The authors extend this stream of studies by showing that the development of HSR networks reduces information processing costs, and promotes the incorporation of firm-specific information in the asset pricing. More importantly, in this study, the authors explicitly incorporate disclosure processing costs theory into our framework thus enhancing our understanding of how and why improvements in transport relate to better market outcomes.

The purpose of this paper is to examine the effects of top management support (TMS) and inter-organizational relationships (IORs) on external involvement (EI), and their differences across different ownerships.

To test the research hypotheses, structural equation modeling was conducted using data from 176 Chinese manufacturing firms.

TMS enhances relationship with customers and relationship with suppliers. Relationship with customers increases the degree of customer involvement, while relationship with suppliers increases the degree of supplier involvement. In addition, TMS improves customer involvement while does not improve supplier involvement directly. A further analysis reveals that the relationship between TMS and supplier involvement is partially mediated by relationship with suppliers in Chinese-controlled firms, whereas it is completely mediated by relationship with suppliers in foreign-controlled firms. Moreover, the effect of relationship with suppliers on supplier involvement is stronger in foreign-controlled firms than in Chinese-controlled firms.

This study employed perceptual data from a single respondent in each firm. In addition, the data used in this study were collected from one side of the dyad: the manufacturers.

Both Chinese-controlled and foreign-controlled firms should get support from top management and develop close relationship with customers and suppliers to improve EI.

This study extends our knowledge in the field by examining how TMS and prior history of IORs can improve the degree of EI.

To retrieve the geometric information contained in CT images, a surface reconstruction method, which is based on the similarity between the corresponding contours of adjacent sections, is presented in this paper. The correspondence of the contours of adjacent sections is determined by incorporating the topological rules and overlaps of the convex hulls of the contours. Then, the similar vertices of the corresponding contours are matched using a two‐phase strategy, consisting of overall matching followed by local matching. Dissimilar portions are extracted to construct the triangulable spatial dissimilar polygons. Finally, triangular meshes interpolating the contours are obtained by triangulating the dissimilar polygons and similar portions separately. The reconstructed surface models can be used in rapid prototyping as well as visualization. Experimental results demonstrate the validity of the method in reconstructing the surface from severe dissimilar contours.

A new type of hydrostatic and hydrodynamic non-contacting face seals has been designed to meet the requirements of lower leakage, longer life and more repeatedly start and stop on shaft seals raised by liquid rocket engine turbopumps. And an experimental study on the performance of the face seal in the actual liquid oxygen turbopump was completed where low-viscosity water was selected as the seal fluid for the sake of safety. The paper aims to discuss these issues.

Different performances of face seals under preset conditions were obtained by repeatedly running tests, and the main performance parameters encompass leakage, fluid film pressure between the faces, operating power, face temperature, and so on.

The results indicate that the designed face seal has a smaller amount of leakage, with a minimum value of 3 ml/s. Furthermore, the designed face seal has been proved to demand lower operating power. Since its operating power changes slightly with different sealed fluid pressures, the new seal can be deployed in the harsh working condition with high pressure or with high speed (greater than 20,000 rpm). However, one proviso is that when liquid is employed as the seal fluid, the groove depth should be relatively deeper (greater than 10 μm).

In response to future engineering requirements, study on the controllable spiral-groove face seals to improve the current design is being conducted.

The advancement of such non-contacting face seals proffers important insights to the design of turbo-pump shaft seal in a new generation of liquid rocket engine with regard to the requirement of frequent start and stop as well as long life on it.

The aims of this study are to conduct a systematic review of public–private partnership (PPP) studies published from 2009 to 2019, to compare the results with Ke et al. (2009) who reviewed the PPP literature published from 1998 to 2008, and to trace the evolution of the PPP knowledge in the past two decades. This study also presents the possible directions that the PPP research may go towards in the future, arguably.

This study carried out a top journal-based search to identify the quality PPP articles published from 2009 to 2019. A total of 12 top-tier construction journals were systematically searched in the database of web of science (WOS), from which 279 PPP articles were identified for review.

The number of the identified articles, the titles of the journals, institutions, the most cited papers, and prevalent research methods were analyzed and compared. The existing PPP studies in construction journals were classified into seven streams. Through analysis of the PPP research status and gaps, five future research directions were revealed.

This study contributes to the current body of knowledge by revealing the research trend of PPP from 2009 to 2019. It presents the change of PPP development trend in the past decade through comparison with Ke et al. (2009). It also reveals the major research streams and points out the directions that the PPP research may go towards in the future. Moreover, this study is helpful to the practice as well. It can enhance the practitioners' understanding of the PPP development in the past decade. In addition, it identified the research institutions contributing the most in the area of PPP, which may serve as valuable reference for practitioners to locate the best institutions for consultancy or collaboration.

Surface acoustic wave (SAW) sensors have attracted great attention worldwide for a variety of applications in measuring physical, chemical and biological parameters. However, stability has been one of the key issues which have limited their effective commercial applications. To fully understand this challenge of operation stability, this paper aims to systematically review mechanisms, stability issues and future challenges of SAW sensors for various applications.

This review paper starts with different types of SAWs, advantages and disadvantages of different types of SAW sensors and then the stability issues of SAW sensors. Subsequently, recent efforts made by researchers for improving working stability of SAW sensors are reviewed. Finally, it discusses the existing challenges and future prospects of SAW sensors in the rapidly growing Internet of Things-enabled application market.

A large number of scientific articles related to SAW technologies were found, and a number of opportunities for future researchers were identified. Over the past 20 years, SAW-related research has gained a growing interest of researchers. SAW sensors have attracted more and more researchers worldwide over the years, but the research topics of SAW sensor stability only own an extremely poor percentage in the total researc topics of SAWs or SAW sensors.

Although SAW sensors have been attracting researchers worldwide for decades, researchers mainly focused on the new materials and design strategies for SAW sensors to achieve good sensitivity and selectivity, and little work can be found on the stability issues of SAW sensors, which are so important for SAW sensor industries and one of the key factors to be mature products. Therefore, this paper systematically reviewed the SAW sensors from their fundamental mechanisms to stability issues and indicated their future challenges for various applications.