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Membrane biological reactor (MBR) is recognized as an efficient and steady wastewater treatment process. The purpose of this study is to reveal the research trends of scientific outputs on MBR for the past 32 years.

A method of bibliometric analysis was performed, based on the online version of the Science Citation Index Expanded, Web of Science, from 1982 to 2013. In total, 5,305 articles related to MBR were evaluated. A new method named “word cluster analysis” was also used for further analysis.

Results showed a rising trend of publications in this research field. English was the main language used in these articles. Journal of membrane science published the most articles, proving to be one of the most authoritative journals. China and Dalian University of Technology were the most productive country and institute, respectively. Except for “membrane bioreactor” and “MBR”, “membrane fouling” was the most cited keyword, indicating the research hotspot nowadays and future.

This study serves as an alternative and innovative way of revealing the research trends in MBR research.

The oil film thickness provides a key performance indicator of a ball bearing lubrication condition. This paper aims to propose an approach to calculate and measure the oil film thickness of the bearing.

On a specially designed test rig, measurement of the capacitance is used to monitor the oil film thickness of ball bearing. A corrected film thickness formula taking account of the influences of non-Newtonian shear thinning and thermal is introduced to predict the oil film thickness of ball bearing. And then the film thickness distribution and the corresponding capacitances are calculated.

Measurement and calculation of oil film thickness in a ball bearing are carried out under various rotating speeds and external loads. By comparing the calculated capacitances with measured results, it can be concluded that the calculated results obtained by the amended film thickness formula are much closer to the test findings than the classical computed values according to Hamrock–Dowson.

A new corrected film thickness formula is introduced in predicting oil film thickness of ball bearing and verified by the series of experiments according to capacitance method.

The paper aims to investigate the possible changes in mean temperature in the Mongolian Plateau associated with the 1.5 and 2°C global warming targets and how snow changes in the Mongolian Plateau when the mean global warming is well below 2°C or limited to 1.5°C.

In total, 30 model simulations of consecutive temperature and precipitation days from Coupled Model Inter-comparison Project Phase 5 (CMIP5) are assessed in comparison with the 111 meteorological monitoring stations from 1961–2005. Multi-model ensemble and model relative error were used to evaluate the performance of CMIP5 models. Slope and the Mann–Kendall test were used to analyze the magnitude of the trends and evaluate the significance of trends of snow depth (SD) from 1981 to 2014 in the Mongolian Plateau.

Some models perform well, even better than the majority (80%) of the models over the Mongolian Plateau, particularly HadGEM2-CC, CMCC-CM, BNU-ESM and GFDL-ESM2M, which simulate best in consecutive dry days (CDD), consecutive wet days (CWD), cold spell duration indicator (CSDI) and warm spell duration indicator (WSDI), respectively. Emphasis zones of WSDI on SD were deeply analysed in the 1.5 and 2 °C global warming period above pre-industrial conditions, because it alone has a significant negative relation with SD among the four indices. It is warmer than before in the Mongolian Plateau, particularly in the southern part of the Mongolian Plateau, indicating less SD.

Providing climate extremes and SD data sets with different spatial-temporal scales over the Mongolian Plateau. Zoning SD potential risk areas and proposing adaptations to promote regional sustainable development.

China’s globalizing Internet describes a situation where China is using the Internet as a tool or medium to transmit its voice on the world stage and enhance its influence over the global Internet governance system and the global digitalization process. Several concerns, however, exist regarding China’s globalizing Internet strategies. This paper aims to respond to these concerns and enhance the understanding of China’s globalizing Internet strategies.

This paper will use content analysis to trace the policy development trajectory of China’s globalizing Internet, including policy vision, policy-making agencies and policy tools.

The Chinese government has issued a considerable number of policies to regulate and promote the development of the Internet since 2014. The key trend that emerged from the analysis of China’s globalizing Internet policy is the cooperation among different agencies. Existing policies have comprehensively used the supply-oriented tools, the environment-oriented tools and the demand-oriented tools; and the last two tools have been used more frequently in recent years.

The analysis results contribute to understanding how China uses digital technology to enhance its influence over the global Internet governance system.

The purpose of this paper is to study the closed-loop guidance algorithm for launch vehicles in an atmospheric ascent phase and present a numerical trajectory reconstruction algorithm to satisfy the real-time requirement of generating the guidance commands.

An optimal control model for an atmospheric ascent guidance system is established directly; following that, the detailed process for necessary conditions of the optimal control problem is re-derived based on the calculus of variations. As a result, the trajectory optimization problem can be reduced to a root-finding problem of algebraic equations based on the finite element method (FEM). To obtain an accurate solution, the Newton method is introduced to solve the roots in a guidance update cycle.

The presented approach can accurately and efficiently solve the trajectory optimization problems. A moderate number of unknowns can yield a good optimal solution, which is well suited for the open-loop guidance. To meet the requirements of the rapidity and accuracy for the close-loop guidance, the fewer number of unknowns is artificially chosen to reduce the calculation time, and the on-board trajectory planning strategy can increase the precision of the optimal solution along with the decrease of time-to-go.

The closed-loop guidance algorithm based on an FEM can be found in this paper, which can solve the optimal ascent guidance problems for launch vehicles in the atmospheric flight phase rapidly, accurately and efficiently.

This paper re-derives the necessary conditions of the optimal solution in a different way compared to the previous work, and the closed-loop guidance algorithm combined with the FEM is also a new thought for the optimal atmospheric ascent guidance problems.

This paper aims to identify key factors influencing the development of advanced manufacturing clusters and propose governance pathways for their digital innovation ecosystems.

A quantitative analysis of the Tai-Xin Integrated Economic Zone in China is conducted using data collected through a questionnaire survey. An evaluation index for the development level of advanced manufacturing clusters is constructed, and a structural equation model is used to identify key influencing factors and governance pathways.

This paper reveals that factors such as industrial foundation, technological innovation capability, social institution environment and government policies have a significant positive impact on the development of digital innovation ecosystem in advanced manufacturing clusters. It constructs a governance model for the digital innovation ecosystem and proposes three major pathways: integration of heterogeneous innovation resources, enhancement of digital capabilities, and fostering digital collaborative governance. The crucial role of digital technology in improving data processing efficiency, optimizing resource allocation and promoting collaboration among entities is emphasized. These pathways can optimize resource allocation, boosting the competitiveness and innovation capacity of clusters.

By incorporating advanced manufacturing clusters into the digital innovation ecosystem framework, this paper enriches theoretical research on both fronts. It offers specific governance pathways and policy recommendations, providing valuable references and guidance for promoting the digital transformation and ecosystem construction of manufacturing clusters.

As a high-performance engineering plastic, polyimide (PI) is widely used in the aerospace, electronics and automotive industries. This paper aims to review the latest progress in the tribological properties of PI-based composites, especially the effects of nanofiller selection, composite structure design and material modification on the tribological and mechanical properties of PI-matrix composites.

The preparation technology of PI and its composites is introduced and the effects of carbon nanotubes (CNTs), carbon fibers (CFs), graphene and its derivatives on the mechanical and tribological properties of PI-based composites are discussed. The effects of different nanofillers on tensile strength, tensile modulus, coefficient of friction and wear rate of PI-based composites are compared.

CNTs can serve as the strengthening and lubricating phase of PI, whereas CFs can significantly enhance the mechanical properties of the matrix. Two-dimensional graphene and its derivatives have a high modulus of elasticity and self-lubricating properties, making them ideal nanofillers to improve the lubrication performance of PI. In addition, copolymerization can improve the fracture toughness and impact resistance of PI, thereby enhancing its mechanical properties.

The mechanical and tribological properties of PI matrix composites vary depending on the nanofiller. Compared with nanofibers and nanoparticles, layered reinforcements can better improve the friction properties of PI composites. The synergistic effect of different composite fillers will become an important research system in the field of tribology in the future.

This paper aims to consolidate prior research from policy and management domains to identify stages in China's technological learning within the imitation paradigm during 1949‐2001, focusing on changes in the government's strategic priorities and policies and the nature, mode and sources of technological learning, then to contrast the firm and institutional features that have emerged under the imitation paradigm with those defining the emerging creation paradigm. The analysis leads to clear implications for both policy and management for the Chinese firms to make this transition and compete in higher value‐added global industries.

An overview and conceptual paper based on observations and literature review.

This paper derives a parsimonious set of four dimensions to demarcate five stages in the evolution of China's technological learning: the government's strategic priority, nature of technology, the mode and the source of learning. It identifies six factors acting as significant impediments to Chinese firms' transition from imitation to creation.

In the first place, this paper provides managerial implications which are of great interest to Chinese practicing managers to manage their firms' transition from imitation to creation; second, the policy imperatives highlighted by this paper will help Chinese policymakers to design appropriate incentive mechanisms to enable Chinese firms to build up their competitiveness within the creation paradigm and thereby become global competitors. Meanwhile, this paper provides a systematic analysis on the evolution of China's technology development. This five stage‐based framework will help practicing managers in China understand whether, which and when Chinese firms can make the transition necessary to compete based on the creation of proprietary resources and capabilities.

Recent research has drawn attention to the tension between the Central and local governments in China regarding their roles in environmental protection. This paper aims to explore this tension and examine the extent to which local/provincial government’s environmental oversight has influenced the quality of corporate environmental disclosure in China.

A sample of 198 listed companies in heavily polluting industries were selected to examine the relationship between their environmental disclosure quality and the respective local government’s environmental oversight level.

The results provide evidence that local/provincial government’s environmental oversight significantly influences environmental disclosure in China. Despite the coercive pressure from the powerful Central government on corporate environmental disclosure, local/provincial governments are able to buffer the pressure and adjust the intensity of their environmental oversight on companies during the implementation of central policies to retain local economic and political interests. This may partially explain the persistent issue of low environmental disclosure quality in China.

This study enriches our understanding of the significant role of local governments in China in enhancing or sometimes discounting the regulatory enforcement of the Central government on corporate environmental disclosure, pointing to the need for concerted efforts by both local and Central governments to advance environmental disclosure development.

Research on environmental disclosure in developed countries has been well established in the literature. However, such research in developing nations is still limited, especially in China, the world largest developing country. The existing literature on environmental disclosure in China links it with either market demands, or regulatory enforcement from the Central government. The importance of local/provincial governments and their environmental oversight has long been ignored, which motivates this research.

This paper describes the organic geochemical characteristics and their roles on barium enrichment in the No. 2 Coal from Huanglong Jurassic Coalfield, China. A total of 18 bench samples were taken from Huangling Mine 2. The average content of barium (3701 mg/kg) was about 23 times higher than that of common world coals. Terrestrial higher plants were the main coal-forming parent material. Relying on the parameters of OEP, Pr/Ph and so on, there is little correlation between organic geochemical characteristics and barium enrichment. Therefore, organic material has little influence on the process of coal-forming and the enrichment of barium.