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SMITH  Z.  WATARI  S.  DRYER  M.  MANOHARAN  P. K.  McINTOSH  P. S. 《Solar physics》1997,171(1):177-190
It is necessary to identify signatures of solar sources in order to improve predictions of solar-caused geomagnetic activity. This is not a straightforward task as the relationship is not well understood. We apply an algorithm, derived from numerical simulations to identify the solar source of an interplanetary event that was observed by the WIND spacecraft on October 18, 1995 and was followed by a geomagnetic storm. No specific geomagnetic activity had been predicted at Space Weather Operations (SWO) in Boulder, CO, on the basis of earlier solar observations. The algorithm is used to estimate the time and location of the expected solar source of this interplanetary event. A review of solar observations prior to the WIND observations showed that solar activity precursors could be identified. A long-duration-event was seen by GOES in soft X-rays at the same time as a type IV burst was observed in metric radio wavelengths, and a rearrangement of fields was observed by the soft X-ray telescope on the Yohkoh satellite. This suggests that the algorithm is useful for post facto identification of solar sources, and that such combinations of solar activity should be further investigated for use in geomagnetic forecasting.  相似文献   
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Based on four phases of TM images acquired in 1990, 1995, 2000 and 2005, this paper took Kitakyushu in Japan as a case study to analyze spatial change of land use landscape and corresponding effects on environmental issues guided by landscape ecology theory in virtue of combining technology of Remote Sensing with GIS. Firstly, land use types were divided into 6 classes (farmland, mountain, forestland, water body, urban land and unused land) according to national classification standard of land use, comprehensible ability of TM image and purpose of this study. Secondly, following the theory of landscape ecology analysis, 11 typical landscape indices were abstracted to evaluate the environmental effects and spatial feature changes of land use. Research results indicated that land use has grown more and more diversified and unbalanced, human activities have disturbed the landscape more seriously. Finally, transfer matrix of Markov was applied to forecast change process of land use in the future different periods, and then potential land use changes were also simulated from 2010 to 2050. Results showed that conversion tendency for all types of land use in Kitakyushu into urban construction land were enhanced. The study was anticipated to help local authorities better understand and address a complex land use system, and develop improved land use management strategies that could better balance urban expansion and ecological conservation.  相似文献   
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