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In order to develop high-strength, high-toughness and high-wear-resistance rails suitable for the development and application of heavy-haul railways.

Based on the trial production of 60 kg·m⁻¹ bainite rails, the Zeiss inverted optical microscope, transmission electron microscope and static hydraulic universal tester were used to test the microstructure and property of rail base metal and welded joints. Meanwhile, a trial laying of rails, wing rails of frogs and switch rails for turnouts was performed to systematically analyze their strength, toughness and wear resistance.

The results show that the base metal of 60 kg·m⁻¹ bainite rail is of a uniform microstructure, with a carbide-free bainite matrix, a few of stable residual austenite and M/A islands, and it features high hardness, good wear resistance and good strength-toughness balance. The welded joint is of a uniform microstructure and has good properties.

A bainite rail, laid in a curve section of heavy-haul railway is able to serve for 48 months with a gross traffic tonnage of nearly 600 million tons, whose service life is more than one time longer than that of pearlite rail; the service life of the wing rail of frog and the switch rail for turnout with 60 kg·m⁻¹ bainite rails is 3–4 times longer than that with U75V rails, and no serious damage occurs. The bainite rails also have strong peeling and spalling resistance.

This study presents a systematic literature review (SLR) of the interdisciplinary literature on drones in last-mile delivery (LMD) to extrapolate pertinent insights from and into the logistics management field.

Rooting their analytical categories in the LMD literature, the authors performed a deductive, theory refinement SLR on 307 interdisciplinary journal articles published during 2015–2022 to integrate this emergent phenomenon into the field.

The authors derived the potentials, challenges and solutions of drone deliveries in relation to 12 LMD criteria dispersed across four stakeholder groups: senders, receivers, regulators and societies. Relationships between these criteria were also identified.

This review contributes to logistics management by offering a current, nuanced and multifaceted discussion of drones' potential to improve the LMD process together with the challenges and solutions involved.

The authors provide logistics managers with a holistic roadmap to help them make informed decisions about adopting drones in their delivery systems. Regulators and society members also gain insights into the prospects, requirements and repercussions of drone deliveries.

This is one of the first SLRs on drone applications in LMD from a logistics management perspective.

This paper analyzes the application of digital twin technology in the field of intelligent operation and maintenance of high-speed railway infrastructure from the perspective of top-level design.

This paper provides a comprehensive overview of the definition, connotations, characteristics and key technologies of digital twin technology. It also conducts a thorough analysis of the current state of digital twin applications, with a particular focus on the overall requirements for intelligent operation and maintenance of high-speed railway infrastructure. Using the Jinan Yellow River Bridge on the Beijing–Shanghai high-speed railway as a case study, the paper details the construction process of the twin system from the perspectives of system architecture, theoretical definition, model construction and platform design.

Digital twin technology can play an important role in the whole life cycle management, fault prediction and condition monitoring in the field of high-speed rail operation and maintenance. Digital twin technology is of great significance to improve the intelligent level of high-speed railway operation and management.

This paper systematically summarizes the main components of digital twin railway. The general framework of the digital twin bridge is given, and its application in the field of intelligent operation and maintenance is prospected.

Unconventional machining processes, particularly ultrasonic vibration cutting (UVC), can overcome such technical bottlenecks. However, the precise mechanism through which UVC affects the in-service functional performance of advanced aerospace materials remains obscure. This limits their industrial application and requires a deeper understanding.

The surface integrity and in-service functional performance of advanced aerospace materials are important guarantees for safety and stability in the aerospace industry. For advanced aerospace materials, which are difficult-to-machine, conventional machining processes cannot meet the requirements of high in-service functional performance owing to rapid tool wear, low processing efficiency and high cutting forces and temperatures in the cutting area during machining.

To address this literature gap, this study is focused on the quantitative evaluation of the in-service functional performance (fatigue performance, wear resistance and corrosion resistance) of advanced aerospace materials. First, the characteristics and usage background of advanced aerospace materials are elaborated in detail. Second, the improved effect of UVC on in-service functional performance is summarized. We have also explored the unique advantages of UVC during the processing of advanced aerospace materials. Finally, in response to some of the limitations of UVC, future development directions are proposed, including improvements in ultrasound systems, upgrades in ultrasound processing objects and theoretical breakthroughs in in-service functional performance.

This study provides insights into the optimization of machining processes to improve the in-service functional performance of advanced aviation materials, particularly the use of UVC and its unique process advantages.

Before the turn of the century, taking overseas students was more about a diplomatic issue dominated by the state in China, for which reason this section is relatively independent within the higher education system. However, evidence from a series of new policy documents and their impacts suggests that international student mobility (ISM) has been intensively shaped by the central government in the desire to promote its national strategy, namely the belt and road initiative. ISM policy, although with a significant proportion marketized, was introduced for a clear purpose of cultural diplomacy. The paper aims to discuss these issues.

Looking beyond the debate of market-driven vs state-dominated, this paper attempts to provide a thorough understanding of this changing pattern based on examination of key changes of policy statements along with official data analysis.

This paper argues that the new pattern must be understood against a context of a hierarchy of higher education institutes in contemporary China: a sector led by a small number of prestigious universities generously funded by the central government with a large number of ordinary universities underfunded and eager to generate income. Prestigious institutes enroll international students to satisfy performance indicators listed by policies like “Double First-rate”; other universities, benefiting from the reputation and momentum generated by the top ones, take self-funded students for profit.

By making good use of both performance indicators and market motives, the country managed to move a state-dominated ISM policy in the twentieth century into the existing state-steering marketization model and made China a major destination for overseas study.

The purpose of this paper is to present a high accuracy path following method for low-cost fixed-wing UAVs.

The original vector field (VF) algorithm is condensed. A spatial integration mechanism is added to the existing VF and nonlinear guidance law, aiming to decrease steady-state cross-track-error and cope with long-term disturbance.

Numerical simulations show the proposed method could diminish steady-state cross-track-error effectively. Test flights show the proposed method is applicable on low-cost fixed-wing UAVs.

The path following accuracy shown in simulations and test flights indicates the proposed method could be deployed in scenarios including inflight rendezvous, formation, trafficway take-off and landing.

This paper provides an improved high-accuracy path following method for low-cost fixed-wing UAVs.

The purpose of this paper is to assess the impacts on production of five fruit crops from 1961 to 2018 of energy use, CO₂ emissions, farming areas and the labor force in China.

This analysis applied the autoregressive distributed lag-bound testing (ARDL) approach, Granger causality method and Johansen co-integration test to predict long-term co-integration and relation between variables. Four machine learning methods are used for prediction of the accuracy of climate effect on fruit production.

The Johansen test findings have shown that the fruit crop growth, energy use, CO₂ emissions, harvested land and labor force have a long-term co-integration relation. The outcome of the long-term use of CO₂ emission and rural population has a negative influence on fruit crops. The energy consumption, harvested area, total fruit yield and agriculture labor force have a positive influence on six fruit crops. The long-run relationships reveal that a 1% increase in rural population and CO₂ will decrease fruit crop production by −0.59 and −1.97. The energy consumption, fruit harvested area, total fruit yield and agriculture labor force will increase fruit crop production by 0.17%, 1.52%, 1.80% and 4.33%, respectively. Furthermore, uni-directional causality is correlated with the growth of fruit crops and energy consumption. Also, the results indicate that the bi-directional causality impact varies from CO₂ emissions to agricultural areas to fruit crops.

This study also fills the literature gap in implementing ARDL for agricultural fruits of China, used machine learning methods to examine the impact of climate change and to explore this important issue.

Fans are proactive consumers of pop culture products, who can be seen as prosumers. Fanvideo production is one of their most widespread practices in the participatory culture scenario. Thus, the aim of the present study is to analyze how ludic prosumption is featured on plays performed in Brazilian fanvideos based on successful pop culture franchises.

Research based on the interpretive content analysis of fanvideos of plays produced by Brazilian fans based on five emblematic pop culture franchises and published on YouTube.

Results have shown six play types in the analyzed fanvideos – i.e. child's play, performing powers, cosplay, play in social rites, teaching to play and “zuêra” –, which revealed a way of having fun in different situations through different practices based on ludic consumption experiences in different spheres of social life.

CCT-based studies focused on investigating plays as ludic consumption phenomenon, as well as fan culture, remain at early research stage. Thus, the main contribution of the present study lies on associating such concepts based on the concept of prosumption.

Carbon trading mechanism has been adopted to foster the green transformation of the economy on a global scale, but its effectiveness for the power industry remains controversial. Given that energy-related greenhouse gas emissions account for most of all anthropogenic emissions, this paper aims to evaluate the effectiveness of this trading mechanism at the plant level to support relevant decision-making and mechanism design.

This paper constructs a novel spatiotemporal data set by matching satellite-based high-resolution (1 × 1 km) CO₂ and PM_2.5 emission data with accurate geolocation of power plants. It then applies a difference-in-differences model to analyse the impact of carbon trading mechanism on emission reduction for the power industry in China from 2007 to 2016.

Results suggest that the carbon trading mechanism induces 2.7% of CO₂ emission reduction and 6.7% of PM_2.5 emission reduction in power plants in pilot areas on average. However, the reduction effect is significant only in coal-fired power plants but not in gas-fired power plants. Besides, the reduction effect is significant for power plants operated with different technologies and is more pronounced for those with outdated production technology, indicating the strong potential for green development of backward power plants. The reduction effect is also more intense for power plants without affiliation relationships than those affiliated with particular manufacturers.

This paper identifies the causal relationship between the carbon trading mechanism and emission reduction in the power industry by providing an innovative methodology for identifying plant-level emissions based on high-resolution satellite data, which has been practically absent in previous studies. It serves as a reference for stakeholders involved in detailed policy formulation and execution, including policymakers, power plant managers and green investors.

The purpose of this paper is to investigate the effect of remelting each layer on the homogeneity of nickel-titanium (NiTi) parts fabricated from elemental nickel and titanium powders using laser powder bed fusion (LPBF). In addition, the influence of manufacturing parameters and different melting strategies, including multiple cycles of remelting, on printability and macro defects, such as pore and crack formation, have been investigated.

An LPBF process was used to manufacture NiTi alloy from elementally blended powders and was evaluated with the use of a remelting scanning strategy to improve the homogeneity of fabricated specimens. Furthermore, both single melt and up to two remeltings were used.

The results indicate that remelting can be beneficial for density improvement as well as chemical and phase composition homogenization. Backscattered electron mode in scanning electron microscope showed a reduction in the presence of unmixed Ni and Ti elemental powders in response to increasing the number of remelts. The microhardness values of NiTi parts for the different numbers of melts studied were similar and ranged from 487 to 495 HV. Nevertheless, it was observed that measurement error decreases as the number of remelts increases, suggesting an increase in chemical and phase composition homogeneity. However, X-ray diffraction analysis revealed the presence of multiple phases regardless of the number of melt runs.

For the first time, to the best of the authors’ knowledge, elementally blended NiTi powders were fabricated via LPBF using remelting scanning strategies.