The terms "Web 3.0" and "Metaverse" now both refer to the third generation of the Internet. A theoretical framework for Web 3.0/Metaverse is constructed, which consists of three parts. The first part is the Web 3.0/Metaverse architecture, including the structure of the Internet at the Web 3.0/Metaverse system level and the structure of computers as the Internet end systems at the Web 3.0/Metaverse component level. The second part is the Web 3.0/Metaverse technology system, including nine Web 3.0/Metaverse technologies. The third part is the Web 3.0/Metaverse application world, which structurely integrates the virtual and real worlds into one and covers five fields, namely economy, politics, military, society, and culture, in either function or scene. A Web 3.0/Metaverse application system is a field or subsystem, or sub-subsystem, etc. of the Web 3.0/Metaverse application world. A kind of Web 3.0/Metaverse application, digital twinning, is analyzed. The first-principle of blockchain is proposed: in the Web 3.0/Metaverse application world, the core function of blockchain is to make contrust (common trust).

Brain science is regarded as the "ultimate frontier" to understand the relationship between universe, nature and human beings, and human beings have never stopped exploring human brain and imitating its mechanism. In the past few centuries, human beings have gained certain understanding of the anatomical structure of human brain and unique functions of each part of the human brain, but its information processing mechanism, the formation of intelligence and other issues need to be further explored. At the same time, it is of great significance to investigate the information processing way of human brain to the study of brain-like intelligence, which plays an important role in expansion and application of human intelligence and is the next goal of AI. Based on extensive research on brain science and brain-like intelligence research at home and abroad, this paper addresses some key scientific issues from a perspective of AI technology in terms of brain information processing mechanism driven by big data, human intelligence formation mechanism based on multiple brain regions collaboration, development mechanism of brain diseases with multi-marker linkage and the mechanism of brain-like depth computing based on multi-modal fusion. It is also suggested to strengthen brain science and brain-like intelligence research from the aspects of interdisciplinary integration, industry-university-research cooperation promotion, international exchange and sharing, strategic planning and deployment, training of scientific talents and so on.

Triboelectric nanogenerator (TENG) has become an emerging platform technology for achieving mechano-electrical energy conversion, with huge application potentials in a variety of fields. For the past decade, through extensive efforts, significant progress on the research of TENG has been made worldwide, including both fundamental scientific research and application technology of TENGs. Therefore, this article aims to review the representative achievements of TENGs in fundamental findings and technological innovations and look forward to the faster development of TENGs.

Quality 4.0 is an emerging quality management concept, which has been increasingly appreciated due to intensification of competition, continually changing customer requirements, and technological evolution. It deals with aligning the practices of quality management with the emergent capabilities of Industry 4.0 to improve cost, time and efficiency as well as increase product quality. As the future of quality, Quality 4.0 has become a potential choice for enterprises and has attracted increasing attention in recent years. In the literature, many studies have been conducted to investigate Quality 4.0 from different perspectives. They provide valuable insights and interesting research suggestions concerning Quality 4.0. However, the current researches on Quality 4.0 are insufficient in terms of basic concept, architecture design and key technologies. Therefore, this paper tries to improve the concept of Quality 4.0 by clarifying the definition, features and goals of Quality 4.0 based on a comprehensive review of current researches and practices. Then, a basic architecture of Quality 4.0 is presented by including physical layer, edge layer, analysis layer and decision layer. Besides, eight key technologies, i. e., industrial big data, digital twins, machine learning, machine vision, visualization technology, optimization techniques, connect technology, and collaborative technology, are identified to support the implementation of Quality 4.0. Finally, the problems of Quality 4.0 implementation in the Chinese manufacturing industry and the possible solutions to address them are discussed.

The World Federation of Scientific Workers, which was founded in 1946, is a non-governmental organization initiated by the British Association of Scientific Workers and other groups. Its members are scientific workers' groups from eastern and western countries. Since the establishment of the WFSW, China has been an important member of it, and has experienced its establishment, development and decline. This article summarized the development history of the WFSW by analyzing the relevant reports and archives of People's Daily, analyzed the development of the relationship between China and the WFSW from 1949 to 1966, and discussed in detail the interaction between China and the WFSW during this period. Then the article pointed out that the WFSW was an important international platform for China to contact western capitalist countries and publicize the political stand of New China during the period from 1949 to 1966. The Chinese government and the scientific community are the important forces to promote the development and growth of the WFSW. At the same time, participating in a series of meetings of the WFSW is a typical case in which the Chinese government serves the country's diplomacy through international activities of the scientific community. Besides, it still has certain reference significance for the development of China's diplomatic work at present.

This study fully collects public data from industry authorities, uses sampling surveys and typical survey methods, and concludes that the total number of scientific and technological workers in China by the end of 2020 is 58.3578 million. Large as the scale is, there is still considerable room for improvement in talent intensity. The study argues that young people have become the main body of scientific and technological workers in China but their innovative and creative vitality is facing many constraints. Those with bachelor's degree or above have become the main body of the workers in China but strategic scientists and first-class innovative talents are lacking. The professional structure of Chinese workers adapting to the high-quality development of economy and society needs to be improved. Maintaining a reasonable structure of academic and vocational education is an urgent task. The sense of identity and professional recognition of scientific and technological workers in China is still insufficient and it is necessary to continue to exert efforts to promote the spirit of scientists and enhance the sense of professional honor and mission.

The poor toughness of liquid molding bismaleimide resin (BMI) had hampered its application in the aeronautics and space field before core-shell particles with double-layer structure were introduced to toughen BMI. The fracture morphology of BMI was studied by scanning electron microscopy (SEM) showing that the fracture surfaces of the toughened BMI were ductile fracture morphology owing to crack propagation blocked. In addition, the content of core-shell particles was adjusted to perfectly improve the comprehensive performance of BMI. Compared to the neat BMI, toughened BMI exhibits excellent mechanical performance with a tensile strength of 108.8 MPa, increased by 13.1%, an elongation at break of 3.12%, increased by 16.8%, a flexural strength of 190 MPa, increased by 12.4%, a K_Ic of 2.83 MPa/m^1/2, increased by 20.9%, and a G_Ic of 1619 J/m², increased by 54.6%. Moreover, the toughened BMI can maintain heat resistance and thermal stability, with glass transition temperature of 292.3°C and 5% weight loss temperature of 401.0°C.

As a non-carbon clean energy, geothermal energy plays an important role in promoting the development goals of carbon peak and carbon neutrality due to its advantages of stable and continuous supply. The utilization of geothermal energy is generally divided into geothermal power generation, geothermal direct utilization and geothermal energy storage. Since 2010, global geothermal direct utilization has grown exponentially, with the installed capacity of geothermal direct utilization and annual heat utilization of about 108 GWt and 283,580 GWh, respectively. China has long ranked first in the world in terms of geothermal direct utilization. The geothermal heat pump system shows an exponential growth of about 16% every year, and the geothermal heat pump system accounts for about 72% and 60% of the installed capacity and heat utilization of the global direct utilization of geothermal heat, respectively. The average annual growth rate of geothermal power generation from 2010 to 2020 is about 4% restricted by high-temperature geothermal resources. Geothermal energy storage is the frontier field of geothermal utilization. Europe and the United States have deployed the "HEATSTORE" and "Geothermal Battery" energy storage projects respectively. The geothermal energy storage project deployed by the Geothermal Team of the Chinese Academy of Sciences has also entered the stage of key technology research and demonstration projects construction. As a huge natural energy storage, geothermal storage is the most suitable basis for storing energy and realizing a stable supply of thermal energy in a multi-energy complementary system. It can save other energy sources across seasons, realize efficient and large-scale energy storage across seasons, and improve energy utilization efficiency. Therefore, it can help achieve the development goals of carbon peak and carbon neutrality.

This paper summarizes five characteristics of China's standardization "going out" in terms of innovation ability demand, domestic and foreign policies, development stage transformation, existing problems and breakthrough points. Around the government, scientific research institutions and enterprises respectively from the "strategy and policy formulation, theory and decision support, standard development and participation" and other aspects of China's standard "going out" optimization path.

To explore the application universality and prospect of carbon nanotube film (CNTF) in curing of resin-matrix composites via resistance heating, CCF800H/EC120A carbon fiber reinforced resin matrix composites were treated by CNTF electric heating cure. To optimize the electrothermal curing process, effects of electricthermal cure processes assisted with vacuum and with press mould on internal quality, glass transition temperature, mechanical properties and microstructure of composites were compared, thus identifying the roles of vacuum degree and external pressure in the electrothermal curing process. The results show that the CNTF can achieve rapid and uniform heating. Compared with press-moulded composite laminates cured by CNTF, composite laminates cured by CNTF within vacuum sealed bag own better internal quality, higher Tg and higher mechanical property, indicating that during the cure process of such prepreg, vacuum degree plays a more significant role than the external pressure in controlling internal quality and performance of obtained laminates. Bending strength of laminates cured by CNTF within vacuum sealed bag maintains at 90% of that cured by traditional oven cure，bending moduli of both cure methods are similar and laminar shear properties also show minor differences.

Ultrasonic borehole imaging while drilling is a cutting-edge technology in the field of measurement and control for drilling. It can generate high-resolution borehole images in real time under the working conditions of drilling. The borehole images can accurately reflect borehole shape, identify fractures, pores, bedding and other characteristics, and play an important role in monitoring borehole engineering condition and quality. To summarize ultrasonic borehole imaging while drilling, based on a large number of literature research, this paper expounds the imaging principle and system components, summarizes the development process and current situation, analyzes and studies the characteristics of the latest oversea research and development of ultrasonic borehole imaging while drilling tools, and summarizes the development trend, in order to provide reference for the development of ultrasonic borehole imaging in China.

Along with "promoting the construction of hydrogenation facilities" written into the government work report, release of development of hydrogen energy for the 2021-2035 period and approval of 5 fuel cell vehicle demonstration city clusters, hydrogen energy and fuel cell industries in China are developing rapidly. In 2022, China completed 109 new hydrogen refueling stations, and has built 358 hydrogen refueling stations till the end of 2019, all ranking first in the world. The overall construction of hydrogenation facilities in China is characterized by "more, faster, synergy and innovative”. However, there still are many problems in the high-pressure and large-displacement HRS equipment technologies, hydrogen pricing mechanisms and quality testing etc. It is suggested that the government should promote enterprises to enhance collaborative innovation and break through the bottleneck of core equipment, improve the hydrogen pricing mechanism and regularly test the quality of hydrogen, and promote the high-quality development of hydrogenation facilities.

We summarize Loo-Keng Hua's important update on economic optimization theory before his immortal death, which unfortunately fell asleep for 37 years and was not awakened until the end of 2021. Next, we introduce its subsequent progress, including one revision, one re-update, and five new developments: a new method for stability analysis; product (industry) level (ranking); prediction and adjustment; optimization of economic structure; efficient algorithms for reordering and large matrix principal eigenvalues (as well as the top 6 eigenvalues in major and minor order). It is rare that multiple transformations provide exactly the same unstable time and product. In the early years, the proof of the Hua's economic collapse theorem was based on the ergodic theorem of the Markov chain, and the recent results are all based on the transition probability matrix of the Markov chain, which may be seen as a new approach to economic optimization research. These achievements have been applied to one provincial-level and five national level input-output tables in China, testing the rationality and reliability of the theory.

With the arrival of the second quantum revolution, quantum technology is having a disruptive impact on scientific cognition and technological application. Why is the United States always in the forefront of quantum technology in the world？On the one hand, it benefits from its strong scientific and technological foundation and economic strength, on the other hand, it is due to its high-level scientific dissemination ability and high scientific literacy of citizens. This paper tries to analyze the original intention and evolution path of the US government's policy design, the linkage promotion mode of scientific research and education system, the efficient incubation and promotion mode of industry and market institutions, the embedding behavior of public and private social organizations and science dissemination individuals, and to refine the typical experience of the design and implementation of the socialized dissemination of quantum technology by studying the socialized collaborative dissemination strategy of American quantum technology. On this basis, this paper believes that the socialized collaborative dissemination of quantum technology in the US has three main implications for China at present: Relying on the institutional advantages, we should accelerate the construction of scientific dissemination and socialization system of quantum science and technology, establish a quantum science and technology education content supply system of basic education-higher education-vocational education, and cultivate multi-level high-level science and technology agents in the field of quantum science and technology.

The curing process and cure kinetics of a high-temperature cured adhesive foam have been investigated by dynamic differential scanning calorimetry (DSC) experiments. In the DSC measurements，heating rates of 1, 2.718, 7.389 and 20 K·min^-1 were used such that lnβ would be 0, 1, 2 and 3, therefore, values of T₁ and ΔT could be easily and quickly determined so as to estimate the apparent activation energy more easily. Linear relationships have been proven to frequently exist between T_p with lnβ by means of a series of reference data from papers about heating cure, thermal decomposition and crystallization of some polymers. The obtained linear equation of T_p versus lnβ can be used to explain some laws for higher or lower of apparent activation energies (E_a), and the apparent activation energy (E_a) can be quickly determined.

This paper introduces the working principle of some new technologies of shallow geothermal and mid-deep geothermal utilization innovative technologies such as aquifer thermal energy storage (ATES), river water source heat pump, ice source heat pump, shallow infiltration seawater source heat pump, comprehensive energy of ground source heat pump and geothermal gradient utilization. By investigating the application cases of these technologies in the Yangtze River Delta region, this paper focuses on the analysis of their advanced technologies, excellent economy and the main problems to be solved. According to their respective characteristics, the prospects for the promotion and application of these innovative geothermal utilization technologies in regions rich in geothermal resources in China, including the Yangtze River Delta, are forecasted. For aquifer energy storage, well completion technology should be optimized to avoid damage to the underground environment. The difficulties in the promotion of river water source heat pump lie in operation management. Ice source heat pump puts forward higher requirements for the preparation and transportation system of ice slurry. The implementation of shallow infiltration seawater source heat pump project must have suitable hydrogeological conditions. The ground-source heat pump integrated energy technology emphasizes the diversification and complementarity of the energy supply system, while the geothermal integrated cascade utilization technology highlights the energy gradient of the energy consumption system. The key to the promotion of these two technologies is economy.

Small neutrino detectors have a wide range of application prospects in reactor monitoring, submarine detection and geophysics research. This paper summarizes the types of neutrinos and detection principles, followed by the development status of detection technologies at home and abroad, including experiments based on inverse beta decay and coherent scattering experiments of neutrinos. Finally, the development of small neutrino detectors is reviewed and differences between different countries and the future development of small neutrino detectors in China are also summarized.

Under the double influence of the digital technology wave and the territorial space planning reform, comprehensive transportation planning is facing the challenge of transformation and upgradation of thought and technology. To fully integrate the whole process of comprehensive transportation planning into national space planning, this paper reviews the challenges and requirements of the digital transformation of comprehensive transportation planning under the national space planning system, and proposes a digital technical framework for comprehensive transportation planning. The paper thinks and explores how to make a digital transformation of comprehensive transportation planning from the aspects of accelerating the transformation of digital thinking of comprehensive transport planning, exploring the formation of transformation development mode, building the spatio-temporal data resource center, forming the electronic "one map" of comprehensive transport planning, and improving integrated co-construction and sharing mechanism, so as to provide strong support for the high-quality development of comprehensive transport.

党的二十大报告指出：“尊重自然、顺应自然、保护自然，是全面建设社会主义现代化国家的内在要求。”随着国家“双碳”战略的稳步推进，绿色转型、绿色消费、低碳产业无疑是未来40年时代发展的主旋律。

在《从作用量原理看模仿型与创新型科技发展模式》（《科技导报》2023年第 4期）中，笔者讨论了科技创新（简称科创）的 2种不同模式，现进一步讨论科创思维的内容和层次。人的意念中有一种有价值的存在——追求真善美。真（truth）指人追求真理的意念和行为。科创思维推动知识的积累和科技的进步，创造更加接近真理的科学理论和应用技术原理。科创的起点是站在巨人思维成果的基础上，探寻他人还没有发现的更理性、更客观、更精准或者更系统的自然规律。常见的科创思维模式包括以下5个不断推进的层次。

为了推动长三角地区一体化高质量发展，中国科学院学部于2020年4月设立了“长三角地区地热资源及其综合研究”院士咨询项目。受汪集暘院士的邀请，我全程参加了该项目的工作。2 年来，经过现场调研和研讨，取得了很好的成果。最后，他们将相关成果汇集成册，在《科技导报》予以专集刊出，以飨读者。

世界是在不断变化着的。人眼对于变化着的现象的分辨能力只有1/24s。为了更深层次地洞悉我们所处的客观世界，人类一直在探索提高观察事物变化的时间分辨能力。在ms到ns范围，可以观察研究所有机械运动和物体形态的变化，包括一般的燃烧和爆炸过程 。

Virtual Coupling has been a hot research topic in railways in recent years. The proposed control methods in the existing literature for virtually coupled train sets (VCTS) mainly try to operate train units with the constraint of maintaining a small gap distance, but pay insufficient attention to the needs in the entering station process, which affects the work of VCTS in a station and is thus one of the most important part of VCTS in unban rail transits. To fill this gap, this paper firstly proposes an unsynchronized stopping problem between the train units in a VCTS when entering a station, defines the concept and the calculation method of stopping time difference between the train units. Then, inspired by the multi-agent cooperative control methods in related fields, a cooperative control-based reference curve generating method for VCTS is proposed. Followed by it, a mathematical optimization model to generate the reference curves for the train units in a VCTS is formulated, and a reinforcement learning DQN (deep Q network) based algorithm is designed to solve this problem. Optimized reference curves for each train units are generated automatically, considering the global objects and all constraints of VCTS. Finally, based on the real data of trains and lines from Beijing Metro Line 11, numerical simulation experiments are conducted. Experimental results prove the effectiveness of the proposed method which outperforms a commonly used control method of VCTS in the literature.

以公共交通为导向的开发 (TOD) 是城市公共设施和空间尽量靠近公共交通站点布局和建设，使公共交通站点成为片区内转换核心,构建交通圈、商业圈、生活圈“三圈合一”的城市布局。

The victory of Deep Blue against Kasparov in 1997 and the victory of Alpha Dog over Lee Sedol in 2016 set off the trend of artificial intelligence, however, artificial intelligence still has so far a huge gap behind humans in terms of intelligence level and range of capabilities, which hinders its development. The reason is that there is an unbridgeable boundary between human intelligence and machine intelligence. In this context, machines that rely on symbols pointing to objects can only perform formal calculations in a closed environment but cannot realize intentional calculations in an open environment like humans. Therefore, the complementary advantages of man and machine are particularly important. The current relationship between man and machine is mainly a hard function allocation, whereas the relationship between man and machine in the future digital world would more likely be a flexible division of capabilities. This paper discusses in detail the bottlenecks of artificial intelligence, the first principle of intelligence, and other issues, and gives more in-depth thinking about human-machine problem amid these problems. It is proposed that human-machine hybrid intelligence is the future development direction of artificial intelligence.

This paper summarizes the application of robotics in the three aspects of rail transit, i.e., equipment manu-facturing, maintenance inspection, and operation services. Combined with the development status of intel-ligent robot technology in this field, we summarize the key technology and challenges of robots. Thus to propose the future direction of the cooperation of robotics and rail transit.

Next generation train control system（NGTC）based on Train-Train communication realizes highly efficient train tracking control through three control strategies of constant spacing, constant time interval, and dynamic headway. Since the leader train control is random in the platoon control, how to ensure the safety of the platoon in different control strategies is very important. This paper proposes a Train-Train communication control strategy modeling and verification method based on stochastic priced timed game（SPTG）. Firstly, according to the requirements of different control strategies, a platoon control model including a leader train and follower trains is established by using SPTG automata, and the stability is verified. Secondly, taking time as the cost function, Q-learning is used to obtain the optimal driving strategy of the platoon through the platoon's SPTG automata model. Finally, combined with multi-train operation tracking scenarios, the stability simulation optimization of the platoon is carried out. The result shows that the stability error of the platoon is smaller than that of the random operation of the platoon.

In January 2023, the latest report of American Cancer Statistics in 2023 was published in CA: A Cancer Journal for Clinicians. This report elaborated on the cancer prevalence in America under the COVID-19 pandemic for the first time, described the secular trends in the burden of major cancers, and projected the cancer cases and deaths in 2023. We analyzed the pattern of cancers distribution by geographic area, time, and characteristics of the populations in China and America according to systematical interpretation of the report combined with the cancer statistics in China. We also summarized the current challenges in the development of cancer prevention and control system in China, and provided insights for its construction depending on assessing advancements and underlying reasons of that in America.

With the deepening development of China's reform and opening up and the Belt and Road Initiative, Chinese acupuncture and moxibustion has gradually moved towards the world stage. Under the background of the new era, the clinical application of acupuncture and moxibustion in China has become more extensive, the treatment methods have bloomed, the clinical, basic and theoretical research has been deepened, and the standards and regulations of acupuncture and moxibustion have gradually led the world: The disease spectrum of acupuncture and moxibustion has been continuously expanded, the clinical application has been increasingly extensive; the treatment methods have been innovated and developed; the clinical research has continuously produced high-quality evidence; the standards and specifications have been published one after another; the theoretical system has been constantly improved; the basic research has made breakthroughs; the international development has been deepened, and the localization of acupuncture overseas has been developed rapidly. At the same time, the current development of acupuncture and moxibustion also faces a series of challenges: It is urgent to establish a diagnosis and treatment system that conforms to the rules of acupuncture and moxibustion itself; the evaluation system of clinical efficacy of acupuncture and moxibustion still needs to be improved; the systematic research of acupuncture and moxibustion still needs to be strengthened; the high-quality clinical evidence of acupuncture and moxibustion is still insufficient; the promotion and transformation of acupuncture and moxibustion research results need to be strengthened. Under the new situation of rapid development of science and technology, how to make full use of modern information technology, big data, artificial intelligence to realize the digital transformation and promote the comprehensive development of acupuncture and moxibustion is the only way for the modernization of acupuncture and moxibustion in the future.

At a time of turmoil in the world situation, implementation of scientific system intervention policy is of great significance for effectively dealing with risk challenges. The practice cases of international mission-oriented innovation policy（MOIP）are investigated and compared in terms of of key mission, policy subjects, policy objectives, policy tools and facing up to challenges. It is shown that MOIP has the characteristics of long policy implementation cycle, mission-oriented response to challenges, authority and diversity of policy subjects, multiplicity and specificity of policy objectives, and diversity of policy tools. Suggestions are put forward for China to lay out MOIP, such as strengthening top-level design, scientifically designing strategic direction, strengthening overall coordination, and optimizing and improving policy toolbox.

党的二十大报告指出，要深入推进环境污染防治。中国是全球塑料生产和消费第一大国，党的十八大以来，国家高度重视塑料污染治理，建成了世界上相对完善的塑料循环利用体系，治理成效逐渐显现。但是从总体上看，中国要打赢白色污染防治攻坚战依然面临着诸多挑战。

复合材料是由高性能基体材料与增强体经过特殊成型工艺复合而成的具有两相或两相以上结构的材料，具有性能可设计复合效应、多功能兼容、材料与构件同步制造等特点，并具有高比强度和比刚度、可设计性强、疲劳性能好、耐腐蚀、可整体成型等优点，已成为航空飞行器结构的关键材料之一。

Qian Xuesen was the founder of China's aerospace industry and an internationally renowned scientist and he also was the outstanding representative of China's scientist spirit. This article summarizes the connotation of Qian Xuesen's scientist spirit from six aspects: patriotism, innovation, seeking truth, dedication, collaboration, and education. Qian Xuesen's scientist spirit has injected a permanent scientific spirit and innovative momentum into China's national defense technology innovation and high-level technological self-reliance and self-improvement.

Based on the relevant research literature of disc brake at home and abroad, this paper summarizes the commonly used disc brake models and brake noise research methods, and introduces the application range, advantages and disadvantages of the models and research methods. The control measures of brake friction noise are analyzed from the aspects of optimizing brake structure, changing brake parameters and active control. Finally, the future research direction of disc brake is prospected.

康复医疗工作是卫生健康事业的重要组成部分。加快推进康复医疗工作发展对全面推进健康中国建设、实施积极应对人口老龄化国家战略、保障和改善民生具有重要意义。

With the application of composites in the main load-bearing structure, composite repair technology has become an important part of the service life of composites. The riveting repair method has an important application in rapid repair technology. In this study damage of carbon fiber composite materials was simulated by the central digging runway-shaped hole method, then the stainless steel plate and titanium alloy plate were used to rivet the damaged parts of the composites. The axial tensile tests of the damaged specimen and the two repair parts were carried out, in which a strain gauge was used to monitor the strains of the hole edge and the metal plate center. The test results show that the maximum loads of the repaired parts obtained by riveting the damaged parts of stainless steel, titanium alloy, and composite are the same, which are increased by 65.2% the unrepaired specimen, indicating that the use of metal materials riveting repair has a certain enhancement effect on the bearing capacity of the damaged composite plates and that the repair effects of stainless steel and titanium alloy materials are comparable. In the tensiling process of the repair specimen, the carbon fiber reinforced composite fails before the metal material; the failure strains of the two metal riveted repair parts are only slightly increased as compared to those of the unrepaired ones.

Combs the characteristics and existing problems of road traffic noise pollution prevention and control in China, analyzes the international experience in road traffic noise pollution prevention and control management. Suggestions for further work are put forward through a comparative study. At present, there are many problems in China's urban road traffic noise, such as strong emission sources, large differences between cities, lack of measures and standards, low noise compliance rate in the areas on both sides of the main traffic line and difficult to solve complaints. From the experience of road traffic noise pollution prevention and control in typical foreign countries, a sound road traffic noise pollution prevention and control standard system should be developed, and joint control of quality standards and emission standards should be adopted. China should issue guidance on road traffic noise pollution prevention and control, that the local government should improve the control standards for road traffic noise emission, and that road traffic noise control should be gradually strengthened.

With the increasing demand for long-term oxidation resistance and reusable high-temperature materials in aerospace, SiC/SiC composites are becoming a research hotspot. This paper summarizes the progress in fatigue and creep properties of SiC/SiC composites in recent years, comprehensively analyzes the effects of temperature, load, frequency and gas environment on fatigue properties, as well as the effects of fiber type, temperature and load, frequency and matrix type on creep properties.

Ultrafast science employs ultrafast light sources and ultrafast measurement as the main approaches to understand, apply and control macroscopic matter through the measurement and manipulation of ultrafast kinetic processes of microscopic particles. As one of the most important frontiers in international science and technology, the development of ultrafast science will provide an important impetus for original innovation in numerous disciplines. Its breakthroughs will help to address many important issues related to the vital national needs and public health. This paper focuses on the research of ultrafast laser technology, ultrafast measurement technology and ultrafast dynamics in ultrafast science, mainly introducing their development status, frontier application and future prospect. In-depth analysis of the problems facing the development of ultrafast science in China is provided, and specific recommendations are proposed to promote its development, including strengthening top-level design, promoting industrialization, improving the evaluation mechanism for talent cultivation, supporting major scientific and technological infrastructures, and participating in international big science programs.

Under the situation of rapid economic development emissions of nitrogen oxides (NO_x) from electric power, metallurgy, chemical industry and other industries have posed a huge threat to the ecological environment and human health. Therefore, the country's NO_x emission standards are becoming more and more stringent, NO_x governance is facing severe challenges. Traditional NO_x treatment methods cannot meet increasingly stringent emission standards and the dielectric barrier discharge technology (DBD) has received widespread attention because of its advantages of safety and cleanliness, low price and simple operation. The recent research progress of NO_x removal by dielectric barrier discharge is summarized and discussed, and the NO_x conversion rate, reaction conditions and reaction mechanism are mainly reviewed in terms of reactor structure characteristics, power supply characteristics and gas components. At the same time, the conversion enhancement effect of the dielectric barrier discharge technology in cooperation with various catalysts is also summarized. Finally, challenges, obstacles and future development directions of NO_x removal using dielectric barrier discharge technology are presented.