The libration control problem of space tether system(STS)for post-capture of payload is studied.The process of payload capture will cause tether swing and deviation from the nominal position,resulting in the failure o...The libration control problem of space tether system(STS)for post-capture of payload is studied.The process of payload capture will cause tether swing and deviation from the nominal position,resulting in the failure of capture mission.Due to unknown inertial parameters after capturing the payload,an adaptive optimal control based on policy iteration is developed to stabilize the uncertain dynamic system in the post-capture phase.By introducing integral reinforcement learning(IRL)scheme,the algebraic Riccati equation(ARE)can be online solved without known dynamics.To avoid computational burden from iteration equations,the online implementation of policy iteration algorithm is provided by the least-squares solution method.Finally,the effectiveness of the algorithm is validated by numerical simulations.展开更多
At present,in the world the development of space is undergoing profound changes brought by commercial space,from the traditional government-driven development to the joint government and market promotion.This paper an...At present,in the world the development of space is undergoing profound changes brought by commercial space,from the traditional government-driven development to the joint government and market promotion.This paper analyzes the current status of both foreign and domestic commercial space markets and policies,and then put forward the ideas and inspirations for the development of China’s commercial space market.展开更多
India,despite being a leading space-faring nation,and operating one of the six largest space programmes in the world,has developed little in terms of expressly documented national space policy over its 58-year history...India,despite being a leading space-faring nation,and operating one of the six largest space programmes in the world,has developed little in terms of expressly documented national space policy over its 58-year history of space activity-besides two standalone policy documents primarily designed to address some operational policy issues pertaining to satellite communication services and use of remote sensing data.However,the Indian space programme,given its phenomenal technological advancements and operational maturity achieved over the decades,clearly exhibits evidence of having been continually and consistently guided,since its very inception,by a cohesive and consistent policy so far as its directional and strategic policy aspects are concerned.In other words,there does exist an apparent undeclared policy embedded in the Indian space establishment that has continued to inform and guide its strategic decisions and actions.The objective of the present case-study is to systematically describe the evolution of the national space policy of India,predominantly as implicit policy,as reflected by the key decisions and actions of the Indian national space establishment since beginning of the Indian space programme.This analysis strives to identify the directional and the strategic elements of policy as reflected by the decisions and actions of the space establishment,and the socio-economic,technological,political and institutional factors that have influenced such policies.展开更多
This paper explores the historical discourses of body and space and examines the ways body and space were linked to discussions about collectivizing and individualizing tendencies of radio broadcasting.This discourse ...This paper explores the historical discourses of body and space and examines the ways body and space were linked to discussions about collectivizing and individualizing tendencies of radio broadcasting.This discourse is reconstructed by comparing the writings on radio play aesthetics by the Jewish media scholar Rudolf Arnheim and the Nazi theorist Richard Kolb.My study shows that,contrary to the conception of radio as an apolitical“instrument of culture”(Hans Bredow),Arnheim and Kolb stressed socio-political implications of aesthetic decisions in radio art.By analyzing them,this paper contributes a nuanced understanding of discussions on the politicization of radio.展开更多
The slow progress and lack of fundamental breakthroughs in legislative practices are an important subject for China's space legislation. Oriented by the idea to formulate China's space law as soon as possible,...The slow progress and lack of fundamental breakthroughs in legislative practices are an important subject for China's space legislation. Oriented by the idea to formulate China's space law as soon as possible, it is necessary to solve five key issues. In the national policy, it is needful not only to implement China's space policy and promote the development of the space industry in depth, but also to advance the deep integration of military and civil application in space field. In terms of legal orientation, three features should be reflected upon, including the functional integration of public and private laws, the balance of regulation by substantive and procedural laws, and the effective coordination of domestic and international laws. To this end, both top-level design and implementation should be paid close attention to in order to achieve significant progress in China's space legislation.展开更多
The white paper document titled “China’s Space Activities”, released in November 2000 by the Information Office of the State Council, represents the first time for China to fully, systematically and publicly introd...The white paper document titled “China’s Space Activities”, released in November 2000 by the Information Office of the State Council, represents the first time for China to fully, systematically and publicly introduce to the world China’s space development strategy and concerned policies. Its release is a milestone event in the country’s space history, bearing great importance and profound influence to its future space efforts. The paper here describes the shaping processes of some important new ideas and concepts, including the connotative meaning of “space activities in a broad sense” and the roles and positions of different sectors in such activities. It also briefly discusses related policies concerning the country’s space development and short-term concepts and plans on its civil space activities.展开更多
基金supported by the National Natural Science Foundation of China(No.62111530051)the Fundamental Research Funds for the Central Universities(No.3102017JC06002)the Shaanxi Science and Technology Program,China(No.2017KW-ZD-04).
文摘The libration control problem of space tether system(STS)for post-capture of payload is studied.The process of payload capture will cause tether swing and deviation from the nominal position,resulting in the failure of capture mission.Due to unknown inertial parameters after capturing the payload,an adaptive optimal control based on policy iteration is developed to stabilize the uncertain dynamic system in the post-capture phase.By introducing integral reinforcement learning(IRL)scheme,the algebraic Riccati equation(ARE)can be online solved without known dynamics.To avoid computational burden from iteration equations,the online implementation of policy iteration algorithm is provided by the least-squares solution method.Finally,the effectiveness of the algorithm is validated by numerical simulations.
文摘At present,in the world the development of space is undergoing profound changes brought by commercial space,from the traditional government-driven development to the joint government and market promotion.This paper analyzes the current status of both foreign and domestic commercial space markets and policies,and then put forward the ideas and inspirations for the development of China’s commercial space market.
文摘India,despite being a leading space-faring nation,and operating one of the six largest space programmes in the world,has developed little in terms of expressly documented national space policy over its 58-year history of space activity-besides two standalone policy documents primarily designed to address some operational policy issues pertaining to satellite communication services and use of remote sensing data.However,the Indian space programme,given its phenomenal technological advancements and operational maturity achieved over the decades,clearly exhibits evidence of having been continually and consistently guided,since its very inception,by a cohesive and consistent policy so far as its directional and strategic policy aspects are concerned.In other words,there does exist an apparent undeclared policy embedded in the Indian space establishment that has continued to inform and guide its strategic decisions and actions.The objective of the present case-study is to systematically describe the evolution of the national space policy of India,predominantly as implicit policy,as reflected by the key decisions and actions of the Indian national space establishment since beginning of the Indian space programme.This analysis strives to identify the directional and the strategic elements of policy as reflected by the decisions and actions of the space establishment,and the socio-economic,technological,political and institutional factors that have influenced such policies.
文摘This paper explores the historical discourses of body and space and examines the ways body and space were linked to discussions about collectivizing and individualizing tendencies of radio broadcasting.This discourse is reconstructed by comparing the writings on radio play aesthetics by the Jewish media scholar Rudolf Arnheim and the Nazi theorist Richard Kolb.My study shows that,contrary to the conception of radio as an apolitical“instrument of culture”(Hans Bredow),Arnheim and Kolb stressed socio-political implications of aesthetic decisions in radio art.By analyzing them,this paper contributes a nuanced understanding of discussions on the politicization of radio.
文摘The slow progress and lack of fundamental breakthroughs in legislative practices are an important subject for China's space legislation. Oriented by the idea to formulate China's space law as soon as possible, it is necessary to solve five key issues. In the national policy, it is needful not only to implement China's space policy and promote the development of the space industry in depth, but also to advance the deep integration of military and civil application in space field. In terms of legal orientation, three features should be reflected upon, including the functional integration of public and private laws, the balance of regulation by substantive and procedural laws, and the effective coordination of domestic and international laws. To this end, both top-level design and implementation should be paid close attention to in order to achieve significant progress in China's space legislation.
文摘The white paper document titled “China’s Space Activities”, released in November 2000 by the Information Office of the State Council, represents the first time for China to fully, systematically and publicly introduce to the world China’s space development strategy and concerned policies. Its release is a milestone event in the country’s space history, bearing great importance and profound influence to its future space efforts. The paper here describes the shaping processes of some important new ideas and concepts, including the connotative meaning of “space activities in a broad sense” and the roles and positions of different sectors in such activities. It also briefly discusses related policies concerning the country’s space development and short-term concepts and plans on its civil space activities.
