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Using restored two-dimensional X-ray images to reconstruct the three-dimensional magnetopause

Earth and Planetary Physics 2024年第1期8卷 133-154页

作者： RongCong Wang JiaQi Wang DaLin Li TianRan Sun xiaodong peng YiHong Guo National Space Science Center Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing100049China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China

Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space *** Soft X-ray Imager(SXI)carried by the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)aims to capture two-dimensional(2-D)images of the Earth’s magnetosheath by using soft X-ray ***,the observed 2-D images are affected by many noise factors,destroying the contained information,which is not conducive to the subsequent reconstruction of the three-dimensional(3-D)structure of the *** analysis of SXI-simulated observation images shows that such damage cannot be evaluated with traditional restoration *** makes it difficult to establish the mapping relationship between SXIsimulated observation images and target images by using mathematical *** propose an image restoration algorithm for SXIsimulated observation images that can recover large-scale structure information on the *** idea is to train a patch estimator by selecting noise–clean patch pairs with the same distribution through the Classification–Expectation Maximization algorithm to achieve the restoration estimation of the SXI-simulated observation image,whose mapping relationship with the target image is established by the patch *** Classification–Expectation Maximization algorithm is used to select multiple patch clusters with the same distribution and then train different patch estimators so as to improve the accuracy of the *** results showed that our image restoration algorithm is superior to other classical image restoration algorithms in the SXI-simulated observation image restoration task,according to the peak signal-to-noise ratio and structural *** restoration results of SXI-simulated observation images are used in the tangent fitting approach and the computed tomography approach toward magnetospheric reconstruction techniques,significantly improving

关键词： Solar wind Magnetosphere Ionosphere Link Explorer(SMILE) soft X-ray imager magnetopause image restoration

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Large-scale spatial data visualization method based on augmented reality

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 132-147页

作者： Xiaoning QIAO Wenming XIE xiaodong peng Guangyun LI Dalin LI Yingyi GUO Jingyi REN Key Laboratory of Electronics and Information Technology for Space Systems National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Ordnance Science and Research Academy of China Beijing 100089China

Background A task assigned to space exploration satellites involves detecting the physical environment within a certain ***,space detection data are complex and *** data are not conducive for researchers'visual perceptions of the evolution and interaction of events in the space *** A time-series dynamic data sampling method for large-scale space was proposed for sample detection data in space and time,and the corresponding relationships between data location features and other attribute features were established.A tone-mapping method based on statistical histogram equalization was proposed and applied to the final attribute feature *** visualization process is optimized for rendering by merging materials,reducing the number of patches,and performing other *** The results of sampling,feature extraction,and uniform visualization of the detection data of complex types,long duration spans,and uneven spatial distributions were *** real-time visualization of large-scale spatial structures using augmented reality devices,particularly low-performance devices,was also *** The proposed visualization system can reconstruct the three-dimensional structure of a large-scale space,express the structure and changes in the spatial environment using augmented reality,and assist in intuitively discovering spatial environmental events and evolutionary rules.

关键词： Large-scale spatial data analysis Visual analysis technology Augmented reality 3D reconstruction Space environment

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Gyrokinetic simulation of magnetic-island-induced electric potential vortex mode

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Plasma Science and Technology 2024年第1期26卷 34-41页

作者：王丰李继全曲洪鹏彭晓东 Southwestern Institute of Physics Chengdu 610041People’s Republic of China

Ion temperature gradient(ITG)-driven turbulence with embedded static magnetic islands is simulated by utilizing a gyrokinetic theory-based global turbulence transport code(GKNET)in this *** from the traditional equilibrium circular magnetic-surface average(EMSA)method,an advanced algorithm that calculates the perturbed magnetic-surface average(PMSA)of the electric potential has been developed to precisely deal with the zonal flow component in a non-circular magnetic surface perturbed by magnetic *** show that the electric potential vortex structure inside islands induced by the magnetic islands is usually of odd parity when using the EMSA *** is found that the odd symmetry vortex can transfer into an even one after a steep zonal flow gradient,*** flow shear has been built in the vicinity of the magnetic islands by adopting the PMSA *** phase of the potential vortex in the poloidal cross section is coupled with the zonal flow *** an electric potential vortex mode may be of essential importance in wide topics,such as the turbulence spreading across magnetic islands,neoclassical tearing mode physics,and also the interaction dynamics between the micro-turbulence and MHD activities.

关键词： magnetic islands electric vortex ITG perturbed magnetic flux surface average

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激光主动探测中的“猫眼”目标识别定位算法

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电光与控制 2024年第3期31卷 53-57页

作者：王湛岩刘朋赵志刚彭孝东中国人民解放军63895部队河南焦作454000

激光主动探测是利用光学系统的“猫眼效应”对敌方侦察设备进行探测识别的技术,其核心技术是利用回波精准地找到敌方光学探测器的位置,从而实施对探测器的干扰或其他措施。构建了激光主动探测中激光传输的基本模型,讨论了大气衰减、离... 详细信息

激光主动探测是利用光学系统的“猫眼效应”对敌方侦察设备进行探测识别的技术,其核心技术是利用回波精准地找到敌方光学探测器的位置,从而实施对探测器的干扰或其他措施。构建了激光主动探测中激光传输的基本模型,讨论了大气衰减、离焦量和入射角度等多种条件对激光主动探测的影响;基于激光主动探测的光电回波图像,以实际探测过程中的激光传输特性为基础,创造性地提出了回波功率、目标大小、目标形状3种判据,与传统目标检测算法相结合,实现了对敌探测设备的精确识别定位;通过实例检验,验证了该算法相较于传统算法具有更好的识别能力,且具有较强的通用性和一定的实战应用价值。

关键词：激光传输特性目标检测算法回波功率目标形状大小

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融合字段类型与文本匹配的中文问句解析

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计算机应用与软件 2024年第7期41卷 184-191页

作者：纪相存李大林彭晓东中国科学院国家空间科学中心北京101499 中国科学院大学北京100049

自然语言转SQL语句技术可以帮助用户使用数据库,而WikiSQL数据集对表格内容的保护一定程度上限制了模型的使用,基于此,提出一种融合字段类型与文本匹配的中文问句解析方法。基于SQL结构分解问句解析任务,通过字段类型相关的分隔符将表... 详细信息

自然语言转SQL语句技术可以帮助用户使用数据库,而WikiSQL数据集对表格内容的保护一定程度上限制了模型的使用,基于此,提出一种融合字段类型与文本匹配的中文问句解析方法。基于SQL结构分解问句解析任务,通过字段类型相关的分隔符将表结构信息结合到RoBERTa编码器输入中,并使用结合编辑距离与语义词典的文本匹配来使模型更加鲁棒。在中文数据集TableQA进行测试,该方法取得了最好的效果,正确率达到93.44%。

关键词：自然语言转SQL语句表结构信息 SQL结构文本匹配

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SPRAYING-OXIDATION AND DEPOSITION PROCESS OF Al/Al_2O_3 COMPOSITES

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中国有色金属学会会刊：英文版 1999年第2期9卷 138-142页

作者： peng, xiaodong Li, Yulan Chongqing Univ Chongqing China

１ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｒｅｓｅａｒｃｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｏｆｍｅｔａｌｍａｔｒｉｘｃｏｍｐｏｓｉｔｅｓｈａｓｂｅｅｎｏｎｅｏｆｔｈｅｍｏｓｔａｃｔｉｖｅａｒｅａｓｉｎｍａｔｅｒｉａｌｓｓｃｉｅｎ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｒｅｓｅａｒｃｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｏｆｍｅｔａｌｍａｔｒｉｘｃｏｍｐｏｓｉｔｅｓｈａｓｂｅｅｎｏｎｅｏｆｔｈｅｍｏｓｔａｃｔｉｖｅａｒｅａｓｉｎｍａｔｅｒｉａｌｓｓｃｉｅｎｃｅａｎｄｔｅｃｈｎｏｌｏｇｙｆｏ...

关键词： Al matrix compositessprayingoxidation and depositionstructure and property

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融合轨道动力学的小行星探测器自主视觉定位

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哈尔滨工业大学学报 2024年第5期56卷 19-27页

作者：樊铭瑞张世栋李运牛文龙彭晓东高辰杨震中国科学院国家空间科学中心北京100190 中国科学院复杂航天系统电子信息技术重点实验室(中国科学院国家空间科学中心) 北京100190 中国科学院大学北京100049

针对小行星探测器高精度自主视觉定位问题,提出了一种融合轨道动力学的深空探测器自主视觉定位方法,能修正视觉视觉定位与地图构建算法(simultaneous localization and mapping,SLAM)的定位误差。该方法通过融合轨道动力学的轨道改进技... 详细信息

针对小行星探测器高精度自主视觉定位问题,提出了一种融合轨道动力学的深空探测器自主视觉定位方法,能修正视觉视觉定位与地图构建算法(simultaneous localization and mapping,SLAM)的定位误差。该方法通过融合轨道动力学的轨道改进技术,能够在缺乏表面先验信息、无人工手动标记的场景下,实现探测器的高精度视觉导航,并建立小行星表面稠密三维模型。首先,基于视觉同时定位和建图方法(VSLAM)提取小行星表面特征,通过因子图优化算法估计探测器位姿,设计回环检测提高定位精度;其次,重构行星表面三维模型,实现基于多面体法的行星不规则引力场建模;最后,提出了一种基于轨道动力学的伪相对运动轨道优化算法,将其作为物理约束修正视觉定位累积误差,分析反演视觉初始定轨误差在轨道动力学中的传播过程,实现修正视觉定位累积误差,改善初始定位结果。仿真实验结果表明,融合轨道动力学可以有效提升小行星探测视觉定位的精度,从而实现高精度导航,为深空探测技术的未来发展提供参考借鉴。

关键词：深空探测自主导航轨道动力学视觉SLAM 状态估计

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Studies on apoptosis in bone tumor cells induced by ^(153)Sm

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Nuclear Science and Techniques 2004年第2期15卷 106-110页

作者： ZHUShou-peng xiaodong HANXiao-Feng InstituteofRadiologicalMedicine SoochowUniversitySuzhou215007

The apoptosis in human bone tumor cells induced by internal irradiation with 153Sm was studied. The morphological changes in bone tumor cells were observed by electronic and fluorescent microscopy, as well as DNA agarose gel eletrophoresis. DNA chain fragmentation, microautoradiographic tracing and the inhibition rate of prolif- eration in bone tumor cells exposed to 153Sm with different duration time were examined. It was demonstrated that the bone tumor cells exposed to 153Sm displayed nuclear fragmentation, pyknosis, margination of condensed chroma- tin, and formation of membrane bounded apoptotic bodies, whereas the percentage of DNA chain fragmentation of bone tumor cells increases in direct proportion to the duration of irradiation with153 Sm, as well as DNA ladder for- mation in apoptotic cells. Also a marked inhibition effect of proliferation in bone tumor cells after exposure with 153Sm was observed.

关键词：细胞凋亡骨肿瘤钐核断裂 ^153Sm-EDTMP

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Magnesium-Based Materials for Energy Conversion and Storage

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Journal of Magnesium and Alloys 2021年第6期9卷 2224-2225页

作者： Qian Li xiaodong peng Fusheng Pan National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China

The development of materials for energy conversion and storage systems is essential for the realization of the sustainable and low-carbon society for which China pledged the long-term strategic target to reach peak carbon dioxide(CO_(2))emissions before 2030 and achieve carbon neutrality by *** the progress in this field can improve the utilization of the intermittent harvested renewable energy.

关键词： energy. Storage carbon

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Theory of Resistivity-Gradient-Driven Turbulence in the Presence of Flow

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Chinese Physics Letters 1995年第12期12卷 747-750页

作者： peng xiaodong ZHANG Jinhua GAO Qingdi Southwestern Institute of Physics P.O.Box 432Chengdu 610041

The resistivity-gradient-driven turbulence is investigated in the presence of both poloidal and parallel/toroidal *** saturation,the poloidal flow shear reduces fluctuations at the edge of plasmas,the parallel flow and its shear both reduce fluctuations in the core of *** indicates that the mechanism for a high confinement regime(H mode)may be the turbulence suppression due to the poloidal flow shear at the edge of plasmas,and the mechanism for a very high confinement(VH mode)may be the turbulence suppression due to the toroidal flow and its shear in the core of plasmas.

关键词： turbulence flow resistivity

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