Green and low-carbon development is the theme of today’s urban construction. Rail transit is an important transport infrastructure in cities, which affects urban transport carbon emissions. The impact of urban rail transport on urban carbon emissions was empirically examined. The results show that the construction of urban rail transport has a significant effect on the reduction of urban carbon emissions, and there is heterogeneity in the effect of urban scale. Urban rail transport has produced the “transport substitution” effect, increased new investment opportunities, increased green financial inputs, promoted green technological innovation, and thus reduced urban carbon emissions.

607 papers published in CNKI database and 308 documents published in WOS database from 2014 to 2024 were selected to conduct in-depth analysis and research from the perspectives of the number of publications, high-frequency authors and keywords by adopting CiteSpace visualization research method. The result shows that the number of publications in the field of carbon performance research is on the rise, but a closely cooperating author network has not yet been formed. The hot spots of carbon performance research are mainly focused on low carbon economy and carbon performance, carbon performance evaluation, and the influencing factors and economic effects of carbon performance, and so on. In the future, it is necessary to continue to expand the research perspectives of carbon performance, focus on the research of digital transformation, technological innovation and carbon performance, and strengthen the interdisciplinary cooperation mechanism.

With the increasing application of high voltage direct current transmission(HVDC) in cross regional transmission of new energy, new energy units at the transmission end may not only suffer from voltage dips and high voltage faults, but also face challenges of low and high voltage disturbances caused by DC commutation failures. In order to accurately analyze the impact of wind farm integration on the power system, a four-machine equivalent method was proposed based on doubly fed induction generator (DFIG) to adapt to multiple types of faults at the DC transmission end. Firstly, the general power curve of wind turbines was modeled for low voltage ride through, high voltage ride through, and continuous low and high voltage ride through in accordance with national standards. Next, the single machines that suffer from multiple types of faults from the cut in wind speed to the cut out wind speed was traversed, and the wind turbines in the wind farm was clustered. Finally, a four-machine equivalence method is proposed based on simulation results.

Recent frequent extreme natural disasters and major public health crises have intensified the convergence of traditional and emerging risks, significantly threatening urban public safety. To address the knowledge gap regarding non-traditional risks, a city-level “risk-resilience capacity” assessment framework under the holistic national security paradigm was developed. Four Chinese megacities were evaluated, such as Qingdao, Nanjing, Hangzhou and Dongguan. The results are as follows. Nanjing demonstrates superior economic development capacity, whereas Hangzhou underperforms. Hangzhou leads in social security capacity, contrasting with Dongguan’s deficiencies. Dongguan exhibits the strongest ecological resilience, while Nanjing ranks lowest. The analysis identifies GDP-driven economic capacity and social security expenditure as critical resilience determinants.

To enhance the level of safety management in airport clearance zones and ensure safe operations within these areas, an evolutionary game model between airport management authorities and clearance violators was constructed. An in-depth analysis of the strategic choices was provided made by both parties under different scenario conditions and the underlying reasons for these choices was exploreed. Using MATLAB software, a sensitivity analysis of key parameters was conducted, examining the impact of four crucial factors, such as the probability of detecting violations, penalty severity, compliance operation costs, and non-compliance income, on the system’s evolutionary path and outcomes. The results show that increasing the probability of detecting violations and imposing stricter penalties can effectively encourage violators to shift towards compliant strategies. Furthermore, reducing compliance costs and limiting non-compliance income can further decrease the probability of violations occurring.

Based on 30 provincial-level panel data in China from 2013 to 2022, Focusing on the mechanisms research, AI affects employment in the service sector was examined. The results show that the impact of AI on service industry employment from a national perspective roughly shows a U-shaped relationship and still holds after considering indigeneity issues and robustness tests. In terms of micro-mechanisms, AI positively promotes service industry employment by affecting the structure of the service industry. The extended discussion suggests that the application of AI has a significant positive employment promotion effect on middle-skilled and high-skilled labor force employment in the service industry. In addition, the potential of modern service industry to absorb labor force employment continues to rise compared with traditional service industry. The extended discussion shows that the application of AI has a significant positive effect on the employment of middle-skilled and high-skilled labor in the service industry. In addition, the absorption potential of the modern service industry compared with the traditional service industry for the employment of the labor force continues to rise.

In the new era, the economy calls for high-quality development, and innovative productive forces are the cornerstone of achieving this goal. By employing methods such as literature review, field research and expert interviews, the practical path and application of blockchain technology in the transformation and upgrading of the integration of sports and medical industries in the Guangdong-Hong Kong-Macao Greater Bay Area, as well as regional coordinated development were deeply explored. The research suggests that the Greater Bay Area has significant advantages in policy, economy, society and technology, providing new opportunities for the vigorous development of the integration of sports and medical industries. Faced with the challenges of industrial transformation and upgrading, the construction of a blockchain-based alliance chain for the integration of sports and medical industries in the Greater Bay Area is proposed, integrating technology research and development, platform support, industry application, and service support to build a comprehensive industrial chain. It is aimed to promote the regional coordinated development of the real economy, drive innovation in social governance and the construction of a healthy city, and contribute key strength to achieving the Chinese modernization goals of a strong sports nation, a healthy China and a digital China.

Changpoling National Forest Park is rich in biological resources, excellent in resource endowment and beautiful in ecological environment, which is the natural cornerstone for developing natural education and promoting the harmonious coexistence between man and nature. However, in the long-term practice of nature education, being subject to the management system, resource development and utilization, basic service facilities and marketing strategies and other factors, its natural education potential has not been fully released, and thus has not become an effective way to promote the high-quality development of forest parks. In order to give full play to the long slope ridge national forest park in the natural education potential conditions and advantages, natural education engine leads the long slope ridge national forest park high quality development, the relevant subject need from the service optimization, talent training, marketing innovation and management system in the face of forest park to upgrade, promote forest park natural education career flourish, provide strong power for forest park high quality development, and for Guiyang city ecological civilization and healthy city construction to make due contributions.

Under the “dual carbon” goal, the express delivery industry is being subject to green transformation, and circular express packaging comes into being. However, the promotion process and results are not ideal. An evolutionary game model of express delivery companies, couriers and consumers was constructed, aiming to explore the stability and influencing factors of the evolutionary equilibrium of the three parties in the promotion process of circular express packaging, and it was analyzed and verified using Matlab. The results show that government rewards and punishments, spillover benefits of express delivery companies, and reputation changes prompt express delivery companies to promote circular express packaging. The rewards and punishments of express delivery companies and the psychological benefits of couriers promote their active cooperation. Subsidies and rewards from the government and express delivery companies, as well as psychological benefits for consumers, encourage their active participation.

Based on the economic data from 273 prefectural cities between 2008 and 2021, taking the “Taobao Village” policy as a quasi-natural experiment, the impact of BOP e-commerce on urban high-quality economic development and its mechanisms were explored. The spatial effects involved were further investigated. It is found that BOP e-commerce significantly promotes high-quality urban economic development, the conclusion remains robust across various tests. Regarding the mechanisms, industrial structure, human capital and population density positively moderate the impact of BOP e-commerce on high-quality economic development in China. In terms of spatial effects, the development of BOP e-commerce exhibits spatial spillover effects that can enhance the high-quality economic development of surrounding cities. Therefore, governments at all levels should strengthen support for BOP e-commerce, enhance inter-regional cooperation, and improve the quality of human capital.