The magnetic field disturbances detected by the Phobos-2 spacecraft in 1989 have been suggested to be caused by a ring of dust and/or gas emitted from the Martian moon,Phobos.The physical nature of these"Phobos e...The magnetic field disturbances detected by the Phobos-2 spacecraft in 1989 have been suggested to be caused by a ring of dust and/or gas emitted from the Martian moon,Phobos.The physical nature of these"Phobos events"is examined using results from related investigations over the last twenty years.It is concluded that there is no clear evidence at present to support the association of magnetic field disturbances in the solar wind with Phobos.The situation will be further clarified taking advantage of the multi-spacecraft observations of the Yinghuo-1(YH-1),Mars Express and MAVEN missions beginning in 2012.It is expected that many novel features of solar wind interaction with Phobos(and possibly also Deimos) itself will also be revealed.展开更多
China’s first supercomputer capable of 100 million calculations per second was the YH-1,which was independently developed by the Institute of Computer Science at the National University of Defense Technology(NUDT)bet...China’s first supercomputer capable of 100 million calculations per second was the YH-1,which was independently developed by the Institute of Computer Science at the National University of Defense Technology(NUDT)between 1978 and 1983.YH-1 played an important role in China’s national defense construction and national economic development.It made China one of the few countries in the world to successfully develop a supercomputer.Based on original archive documents,interviews with relevant personnel,and an analysis of the technological parameters of the supercomputers YH-1 in China and Cray-1 in the United States,this paper reviews in detail the historic process of the development of YH-1,analyzing its innovation and summarizing the experience and lessons learned from it.This analysis is significant for current military-civilian integration,and the commercialization of university research findings in China.展开更多
基金supported in part by NSC Grant NSC 96-2752-M-008-011-PAE and Ministry of Education under the Aim for Top University Program NCU
文摘The magnetic field disturbances detected by the Phobos-2 spacecraft in 1989 have been suggested to be caused by a ring of dust and/or gas emitted from the Martian moon,Phobos.The physical nature of these"Phobos events"is examined using results from related investigations over the last twenty years.It is concluded that there is no clear evidence at present to support the association of magnetic field disturbances in the solar wind with Phobos.The situation will be further clarified taking advantage of the multi-spacecraft observations of the Yinghuo-1(YH-1),Mars Express and MAVEN missions beginning in 2012.It is expected that many novel features of solar wind interaction with Phobos(and possibly also Deimos) itself will also be revealed.
文摘China’s first supercomputer capable of 100 million calculations per second was the YH-1,which was independently developed by the Institute of Computer Science at the National University of Defense Technology(NUDT)between 1978 and 1983.YH-1 played an important role in China’s national defense construction and national economic development.It made China one of the few countries in the world to successfully develop a supercomputer.Based on original archive documents,interviews with relevant personnel,and an analysis of the technological parameters of the supercomputers YH-1 in China and Cray-1 in the United States,this paper reviews in detail the historic process of the development of YH-1,analyzing its innovation and summarizing the experience and lessons learned from it.This analysis is significant for current military-civilian integration,and the commercialization of university research findings in China.