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张辉等-GRL:蜿蜒的月球尾迹与太阳风粒子拾取(图)
月球尾迹 太阳风 粒子拾取
2023/1/16
肺纯磨玻璃结节CT定量分析研究进展
肺腺癌 计算机X射线断层术 定量分析 病理
2020/8/26
随着多层螺旋CT的不断发展及临床肺癌CT筛查的逐渐普及,肺内磨玻璃密度结节的检出率显著增加,且大部分被证实与早期肺腺癌密切相关,因此肺内磨玻璃密度结节不断受到国内外学者关注。磨玻璃密度结节的浸润程度与是否手术或手术方法的选择密切相关。因此,对于术前肺内磨玻璃结节CT表现特征与不同病理分型的对照研究有重要的临床价值。全文就目前有关肺纯磨玻璃结节CT定量分析与病理对照研究情况予以综述。
HP3中的共形极小曲面的构造
四元数射影空间 共形极小曲面 扭映射
2019/4/18
通过扭映射π:CP7→ HP3构造出HP3中10族共形极小曲面的例子.根据Eells和Wood在1983年得到的结论,水平调和映射在淹没映射下的像仍然是调和的.首先给出CP7中水平全纯曲面在局部下的一个分类定理.基于该分类定理以及Eells和Wood的结论,利用扭映射,构造出HP3中的共形极小曲面.
多碎片移除过程中的路径优化
空间碎片 移除 路径优化 蚁群算法
2018/5/4
采用蚁群优化算法对多碎片移除过程中的路径优化问题进行研究,然后采用改进的最速下降法对移除每块碎片的时间进行合理优化,进一步降低总的速度增量需求.对比轨道高度、轨道倾角或者升交点赤经的顺序后发现,采用蚁群算法优化之后的顺序移除碎片可以大大节省轨道转移所需要的速度增量.选取中国空间活动产生的三组碎片进行优化计算,结果显示在相同的任务时间内,优化后的顺序可能不同于轨道高度、倾角和赤经的顺序,并且优化顺序...
The chapter discusses generalized method of moments (GMM) estimation
methods for spatial models. Much of the discussion is on GMM estimation of
Cliff-Ord-type models where spatial interactions are m...
On the finite sample properties of pre-test estimators of spatial models
Spatial models Spatial lag models
2015/9/24
This paper explores the properties of pre-test strategies in estimating a linear Cliff–Ord-type spatial model when
the researcher is unsure about the nature of the spatial dependence. More speciʂ...
EUSO: using high energy cosmic rays and neutrinos as messengers from the unknown universe
fluorescence cosmic rays neutrinos extensive air showers
2015/9/16
Exploiting the earth atmosphere as a giant detector for the incoming extraterrestrial fl ux of high energy cosmic rays
and cosmic neutrinos, the mission «EUSO-Extreme Universe Space Observatory&...
ROTATIONAL SIGNATURE AND POSSIBLE r-MODE SIGNATURE IN THE GALLEX SOLAR NEUTRINO DATA
ROTATIONAL SIGNATURE POSSIBLE r-MODE SIGNATURE
2015/8/20
Recent analysis of the Homestake data has yielded evidence that the solar neutrino flux varies in time—more
specifically, that it exhibits a periodic variation that may be attributed to r...
ON THE SOLAR-CYCLE MODULATION OF THE HOMESTAKE SOLAR NEUTRINO CAPTURE RATE AND THE SHUFFLE TEST
SOLAR-CYCLE MODULATION SHUFFLE TEST
2015/8/20
There exists no signiDcant correlation between the Homestake neutrino data up to run 133 and the
monthly sunspot number, according to a test that is based on certain optimality properties for this ty...
APPARENT LATITUDINAL MODULATION OF THE SOLAR NEUTRINO FLUX
SOLAR NEUTRINO FLUX APPARENT LATITUDINAL MODULATION
2015/8/20
We examine the solar neutrino Ñux, as measured by the Homestake neutrino detector, to search for
evidence of a dependence upon the solar latitude of the Earth-Sun line that varies from south in ...