基于1996—2005年88个引起重大地磁暴的CME(日冕物质抛射)事件、1996—2000年的47个CME事件以及1997—2002年的29个全晕状CME事件,结合ACE卫星在1 AU处的太阳风和行星际磁场观测资料以及Wilcox Solar Observatory(WSO)天文台的太阳光球...基于1996—2005年88个引起重大地磁暴的CME(日冕物质抛射)事件、1996—2000年的47个CME事件以及1997—2002年的29个全晕状CME事件,结合ACE卫星在1 AU处的太阳风和行星际磁场观测资料以及Wilcox Solar Observatory(WSO)天文台的太阳光球层磁图,分析了背景太阳风速度和日球电流片对CME到达1 AU处渡越时间预报误差的影响.结果表明,背景太阳风速度与CME渡越时间误差并没有明显的相关性,在考虑了磁云通量管轴相对黄道面夹角的影响后相关性依然不明显.然而日球电流片对CME渡越时间却有明显的影响,对于初速度较小的异侧CME事件,其渡越时间大于同侧事件;而对于具有较大初速度的CME事件,异侧事件的渡越时间明显小于同侧事件.研究结果表明,CME与太阳风以及日球电流片的相互作用并不是简单的对流相互作用,造成高速CME异侧事件快于同侧事件到达地球的因素非常复杂,有待深入研究.展开更多
AIM： To investigate whether suspected blood indicator （SBI） in capsule endoscopy （CE） is affected by back- ground color and capsule passage velocity. METHODS： Experimental models of the small intestine construct...AIM： To investigate whether suspected blood indicator （SBI） in capsule endoscopy （CE） is affected by back- ground color and capsule passage velocity. METHODS： Experimental models of the small intestine constructed from paper in a variety of colors were used to simulate the background colors observed in CE im- ages. The background colors studied included very pale yellow, yellow, very pale magenta, light grayish pink, burnt sienna, and deep and dark brown, and red spots were attached inside them. An endoscopic capsule was manually passed through the models. The rate of detection of the red spots by the SBI was evaluated based on the colors of the models and the capsule pas- sage velocities （0.5 cm/s, 1 cm/s, and 2 cm/s）.RESULTS： The rate of detection of the red spots byground color of the model （P 〈 0.001）. Detection rates were highest for backgrounds of very pale magenta, burnt sienna, and yellow, in that order. They were lowest for backgrounds of dark brown and very pale yellow. The rate of detection of red spots by the SBI tended to decrease at rapid capsule passage velocities （1-2 cm/s） compared to slow velocities （0.5 cm/s） for backgrounds of very pale yellow （P = 0.042）, yellow （P = 0.001）, very pale magenta （P = 0.002）, and burnt sien- na （P = 0.001）. No significant differences in the rate of detection were observed according to velocity for light grayish pink （P = 0.643） or dark brown （P = 0.396）. CONCLUSION： SBI sensitivity was affected by back- ground color and capsule passage velocity in the models. These findings may facilitate the rapid detection of bleeding lesions by CE.展开更多
文摘基于1996—2005年88个引起重大地磁暴的CME(日冕物质抛射)事件、1996—2000年的47个CME事件以及1997—2002年的29个全晕状CME事件,结合ACE卫星在1 AU处的太阳风和行星际磁场观测资料以及Wilcox Solar Observatory(WSO)天文台的太阳光球层磁图,分析了背景太阳风速度和日球电流片对CME到达1 AU处渡越时间预报误差的影响.结果表明,背景太阳风速度与CME渡越时间误差并没有明显的相关性,在考虑了磁云通量管轴相对黄道面夹角的影响后相关性依然不明显.然而日球电流片对CME渡越时间却有明显的影响,对于初速度较小的异侧CME事件,其渡越时间大于同侧事件;而对于具有较大初速度的CME事件,异侧事件的渡越时间明显小于同侧事件.研究结果表明,CME与太阳风以及日球电流片的相互作用并不是简单的对流相互作用,造成高速CME异侧事件快于同侧事件到达地球的因素非常复杂,有待深入研究.
文摘AIM： To investigate whether suspected blood indicator （SBI） in capsule endoscopy （CE） is affected by back- ground color and capsule passage velocity. METHODS： Experimental models of the small intestine constructed from paper in a variety of colors were used to simulate the background colors observed in CE im- ages. The background colors studied included very pale yellow, yellow, very pale magenta, light grayish pink, burnt sienna, and deep and dark brown, and red spots were attached inside them. An endoscopic capsule was manually passed through the models. The rate of detection of the red spots by the SBI was evaluated based on the colors of the models and the capsule pas- sage velocities （0.5 cm/s, 1 cm/s, and 2 cm/s）.RESULTS： The rate of detection of the red spots byground color of the model （P 〈 0.001）. Detection rates were highest for backgrounds of very pale magenta, burnt sienna, and yellow, in that order. They were lowest for backgrounds of dark brown and very pale yellow. The rate of detection of red spots by the SBI tended to decrease at rapid capsule passage velocities （1-2 cm/s） compared to slow velocities （0.5 cm/s） for backgrounds of very pale yellow （P = 0.042）, yellow （P = 0.001）, very pale magenta （P = 0.002）, and burnt sien- na （P = 0.001）. No significant differences in the rate of detection were observed according to velocity for light grayish pink （P = 0.643） or dark brown （P = 0.396）. CONCLUSION： SBI sensitivity was affected by back- ground color and capsule passage velocity in the models. These findings may facilitate the rapid detection of bleeding lesions by CE.
