在国际关系的理论研究和实际操作中,官方发展援助(Official Development Assistance)以其官方背景、政府行为、战略目的等一系列特点,一直是国外援助研究的重要对象。通过分析日本对华发展援助的特点以及冷战后其战略的几次调整,揭示日...在国际关系的理论研究和实际操作中,官方发展援助(Official Development Assistance)以其官方背景、政府行为、战略目的等一系列特点,一直是国外援助研究的重要对象。通过分析日本对华发展援助的特点以及冷战后其战略的几次调整,揭示日本对中国积极推行ODA政策的深层次原因和目的。当今世界格局下,中日关系对亚太地区的影响非常重大,因此,研究长期以来日本对外援助理念对于正确理解和处理中日关系有着重要的意义。展开更多
A novel technique to determine the position of spacecraft orbits is proposed. The technique is based on the cross-correlation function of HF SAR images and is able to determine the relative position of orbits with an ...A novel technique to determine the position of spacecraft orbits is proposed. The technique is based on the cross-correlation function of HF SAR images and is able to determine the relative position of orbits with an accuracy of - λ/4 or better, where 2 is the wavelength of the HF radar pulse at its center frequency. The performance of the proposed technique was confirmed by simulation which was carried out under the condition of design facts of the SELENE LRS mission. The highly accurate orbit positioning enables precise superposition of HF SAR images so that the inherent mirror image ambiguity problem of HF SAR imaging is resolved to obtain a quality SAR image of the HF band. In addition ambitious 2D-SAR processing would be possible when the above accuracy is available.展开更多
文摘在国际关系的理论研究和实际操作中,官方发展援助(Official Development Assistance)以其官方背景、政府行为、战略目的等一系列特点,一直是国外援助研究的重要对象。通过分析日本对华发展援助的特点以及冷战后其战略的几次调整,揭示日本对中国积极推行ODA政策的深层次原因和目的。当今世界格局下,中日关系对亚太地区的影响非常重大,因此,研究长期以来日本对外援助理念对于正确理解和处理中日关系有着重要的意义。
基金supported by the Basic Research Project, "Development of New Geological Technology for Tracing Earth and Planetary Evolution" of the Korea Institute of Geoscience and Mineral Resources (KIGAM)
文摘A novel technique to determine the position of spacecraft orbits is proposed. The technique is based on the cross-correlation function of HF SAR images and is able to determine the relative position of orbits with an accuracy of - λ/4 or better, where 2 is the wavelength of the HF radar pulse at its center frequency. The performance of the proposed technique was confirmed by simulation which was carried out under the condition of design facts of the SELENE LRS mission. The highly accurate orbit positioning enables precise superposition of HF SAR images so that the inherent mirror image ambiguity problem of HF SAR imaging is resolved to obtain a quality SAR image of the HF band. In addition ambitious 2D-SAR processing would be possible when the above accuracy is available.
