In order to solve the problem of experimental research on the penetration process of projectile into anchored rock mass, we derived the essential similarity conditions for the physical simulation experi- ment accordin...In order to solve the problem of experimental research on the penetration process of projectile into anchored rock mass, we derived the essential similarity conditions for the physical simulation experi- ment according to the similarity theory, carried out the experiment on the penetration process of a kind of penetrating bomb into the anchored rock mass of type III, and compared the experimental results with the values computed by the professional Young's empirical formula. The test results show that the phys- ical simulation experiment can represent the actual penetration process of projectile into anchored rock mass. The research method proposed in this paper provides technical support for the experimental research on the design and reconstruction of underground protection works.展开更多
Wetlands are important natural resources for humans and play an irreplaceable ecological function in the terrestrial ecosystem.To curb the continued loss of wetlands globally,international organizations and many count...Wetlands are important natural resources for humans and play an irreplaceable ecological function in the terrestrial ecosystem.To curb the continued loss of wetlands globally,international organizations and many countries have taken a series of major conservation and restoration measures.This work reviews these wetland conservation and restoration measures,interprets China’s wetland conservation and restoration management policies,and proposes that future research on wetland resources in China should be conducted from the aspects of international frontiers and national strategic plans,socioeconomics,and smart services.The results show that the 27 International Wetlands Days from 1997 to 2023 provided new goals and tasks for the protection and management of wetlands.The important topics and outcomes of the 14 Conferences of the Contracting Parties to the Convention on Wetlands from 1980 to 2022 provided new directions and new challenges for wetland development.In the future,we should enhance wetland ecological functions,promote sustainable wetland development,and overcome the technical bottleneck of fragile wetland ecosystem restoration.From 1992 to 2022,China embarked on a new phase of wetland protection and restoration.The overall experience of wetland protection and restoration in China has been formed through national strategic deployment,legal policy establishment,and project planning and implementation.The needs to provide for and plan the long-term protection of wetlands at the national level,to innovate restoration and management techniques and application systems,and to effectively address the complex issues of wetland protection and restoration through collaborative division of labor among multiple departments were emphasized.Research on the future trends of wetlands should be directed towards the exploration and practice of the United Nations Sustainable Development Goals and several international conventions in support of sustainable wetland development.Wetland protection,restoration,and management services should be promoted for national strategic needs and local,high-quality social and economic development.In addition,research on cross-integration and academic innovation should be enhanced for disciplinary development,global supervision,comprehensive assessment,and smart decision making.展开更多
The call for the solicitation of contributions, known as "The Law on the Protection of Minors and I," was sponsored by the Red Scarf Board to Protect Students’ Rights and Interests at the Central Primary Sc...The call for the solicitation of contributions, known as "The Law on the Protection of Minors and I," was sponsored by the Red Scarf Board to Protect Students’ Rights and Interests at the Central Primary School of Majuqiao Township, Tongxian County in the suburbs of Beijing. Shown here are three contributions.展开更多
文摘In order to solve the problem of experimental research on the penetration process of projectile into anchored rock mass, we derived the essential similarity conditions for the physical simulation experi- ment according to the similarity theory, carried out the experiment on the penetration process of a kind of penetrating bomb into the anchored rock mass of type III, and compared the experimental results with the values computed by the professional Young's empirical formula. The test results show that the phys- ical simulation experiment can represent the actual penetration process of projectile into anchored rock mass. The research method proposed in this paper provides technical support for the experimental research on the design and reconstruction of underground protection works.
基金National Natural Science Foundation of China,No.U21A2022,No.42071393,No.U1901219,No.42101369。
文摘Wetlands are important natural resources for humans and play an irreplaceable ecological function in the terrestrial ecosystem.To curb the continued loss of wetlands globally,international organizations and many countries have taken a series of major conservation and restoration measures.This work reviews these wetland conservation and restoration measures,interprets China’s wetland conservation and restoration management policies,and proposes that future research on wetland resources in China should be conducted from the aspects of international frontiers and national strategic plans,socioeconomics,and smart services.The results show that the 27 International Wetlands Days from 1997 to 2023 provided new goals and tasks for the protection and management of wetlands.The important topics and outcomes of the 14 Conferences of the Contracting Parties to the Convention on Wetlands from 1980 to 2022 provided new directions and new challenges for wetland development.In the future,we should enhance wetland ecological functions,promote sustainable wetland development,and overcome the technical bottleneck of fragile wetland ecosystem restoration.From 1992 to 2022,China embarked on a new phase of wetland protection and restoration.The overall experience of wetland protection and restoration in China has been formed through national strategic deployment,legal policy establishment,and project planning and implementation.The needs to provide for and plan the long-term protection of wetlands at the national level,to innovate restoration and management techniques and application systems,and to effectively address the complex issues of wetland protection and restoration through collaborative division of labor among multiple departments were emphasized.Research on the future trends of wetlands should be directed towards the exploration and practice of the United Nations Sustainable Development Goals and several international conventions in support of sustainable wetland development.Wetland protection,restoration,and management services should be promoted for national strategic needs and local,high-quality social and economic development.In addition,research on cross-integration and academic innovation should be enhanced for disciplinary development,global supervision,comprehensive assessment,and smart decision making.
文摘The call for the solicitation of contributions, known as "The Law on the Protection of Minors and I," was sponsored by the Red Scarf Board to Protect Students’ Rights and Interests at the Central Primary School of Majuqiao Township, Tongxian County in the suburbs of Beijing. Shown here are three contributions.
