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Development of D_α band symmetrical visible optical diagnostic for boundary reconstruction on EAST tokamak

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Plasma Science and Technology 2024年第2期26卷 44-53页

作者：陈明沈飊 Shinichiro KADO 郭笔豪陈大龙蔡福瑞肖炳甲 Hefei Institutes of Physical Science Chinese Academy of SciencesHefei 230031People's Republic of China Science Island Branch Graduate School of University of Science and Technology of ChinaHefei 230026People's Republic of China Institute of Advanced Energy Kyoto UniversityUji 611-0011Japan Graduate School of Energy Science Kyoto UniversityUji 611-0011Japan

To investigate the potential of utilizing visible spectral imaging for controlling the plasma boundary shape during stable operation of plasma in future tokamak, a D_α band symmetric visible light diagnostic system was designed and implemented on the Experimental Advanced Superconducting Tokamak(EAST). This system leverages two symmetric optics for joint plasma imaging. The optical system exhibits a spatial resolution less than 2 mm at the poloidal cross-section, distortion within the field of view below 10%, and relative illumination of 91%.The high-quality images obtained enable clear observation of both the plasma boundary position and the characteristics of components within the vacuum vessel. Following system calibration and coordinate transformation, the image coordinate boundary features are mapped to the tokamak coordinate system. Utilizing this system, the plasma boundary was reconstructed, and the resulting representation showed alignment with the EFIT(Equilibrium Fitting) results. This underscores the system's superior performance in boundary reconstruction applications and provides a diagnostic foundation for boundary shape control based on visible spectral imaging.

关键词： visible optical diagnostic plasma boundary reconstruction EAST

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在检查中促提高在自律中求发展

中国注册会计师 2005年第4期 9-10页

作者：朱穗宁沈大龙江苏无锡市注册会计师协会

根据中注协关于开展2004年会计师事务所执业质量检查工作的通知精神,在江苏省注协的直接领导下,我们对无锡市的会计师事务所展开了执业质量检查.目前2004年度的检查已经结束.总结这次检查的成绩和不足,分析检查过程的经验和差距,对于今... 详细信息

根据中注协关于开展2004年会计师事务所执业质量检查工作的通知精神,在江苏省注协的直接领导下,我们对无锡市的会计师事务所展开了执业质量检查.目前2004年度的检查已经结束.总结这次检查的成绩和不足,分析检查过程的经验和差距,对于今后行业执业质量检查,是很有意义的.本文就如何做好检查工作,谈一些体会.

关键词：执业质量检查工作会计师事务所自律 2004年度直接领导中注协江苏省无锡市精神行业

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基于最小二乘法的压缩文本图像恢复算法

计算机工程与应用 2002年第2期38卷 36-38页

作者：沈大龙任东陈增强袁祉天津市计算机研究所天津300061 南开大学自动化系天津300071

文章采用基于算术编码的压缩方法对文本图像进行无损压缩和传送,进而提出基于最小二乘法灰度插值的压缩文本图像的恢复算法,它将高度结构化的灰度图像分解为多个线性模型,估计出模型参数,从而重构出灰度文本图像,明显改善了屏幕浏览的... 详细信息

文章采用基于算术编码的压缩方法对文本图像进行无损压缩和传送,进而提出基于最小二乘法灰度插值的压缩文本图像的恢复算法,它将高度结构化的灰度图像分解为多个线性模型,估计出模型参数,从而重构出灰度文本图像,明显改善了屏幕浏览的视觉效果。

关键词：图像处理无损压缩最小二乘法文本图像恢复算法算术编码计算机

基于水合物生成的多机制耦合储存天然气实验研究

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当代化工 2024年第2期53卷 330-333,337页

作者：陈伟伟沈阳窦大龙中国石油长庆油田分公司第五采气厂陕西西安710016

探索了基于水合物生成的多机制耦合储存天然气的方法,以提高储存效率并降低环境影响。对不同温度、压力以及不同有机催化剂的使用对水合物生成和稳定性的影响进行了实验研究。结果表明:在低温(-5~15℃)和高压(3~12MPa)条件下,使用特定... 详细信息

探索了基于水合物生成的多机制耦合储存天然气的方法,以提高储存效率并降低环境影响。对不同温度、压力以及不同有机催化剂的使用对水合物生成和稳定性的影响进行了实验研究。结果表明:在低温(-5~15℃)和高压(3~12MPa)条件下,使用特定催化剂显著提高了水合物的生成速率和稳定性。特别是在-5℃和12MPa条件下,使用CAT-4502催化剂时,水合物的生成量达到最大值650m L,而稳定性评分(分解时间)高达84h。此外,水合物技术在温室气体排放和能源消耗方面表现出优越性,相比传统储存方法,可减少约40%的温室气体排放和38%的能源消耗。本研究为天然气的高效储存提供了新的视角,并展示了水合物技术在环境友好性和经济可行性方面的潜力。

关键词：天然气水合物多机制耦合储存催化剂效应环境影响评估

基于免训练自监督式神经网络算法实现压缩超快成像高保真图像重构

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科学通报 2024年第19期69卷 2765-2776页

作者：金诚挚齐大龙何宇姚佳丽郭姿含许宁程龙毛佳亿姚志明宋岩姚云华沈乐成邓联忠盛亮孙真荣张诗按华东师范大学物理与电子科学学院精密光谱科学与技术国家重点实验室上海200241 西北核技术研究院强脉冲辐射环境模拟与效应国家重点实验室西安710024 山西大学极端光学协同创新中心太原030006 华东师范大学华东师范大学-山东师范大学光场调控科学与光子芯片器件联合研究中心上海200241

压缩超快成像(compressed ultrafast photography,CUP)是目前最快的被动式单次超快光学成像技术,它通过数据获取和图像重构两个步骤实现超快事件的捕捉,已发展为记录不可逆或难以重复超快事件的一种有力工具,且能够探测荧光动力学等自... 详细信息

压缩超快成像(compressed ultrafast photography,CUP)是目前最快的被动式单次超快光学成像技术,它通过数据获取和图像重构两个步骤实现超快事件的捕捉,已发展为记录不可逆或难以重复超快事件的一种有力工具,且能够探测荧光动力学等自发光瞬态场景.然而,传统的迭代优化型算法在图像重构上的保真度较低,而端到端型深度学习算法则严重依赖训练数据,训练复杂度高、通用性不足,这限制了CUP对超快现象进行高空间分辨率的观测.为此,我们开发了一种新型的免训练自监督式神经网络算法,其通过即插即用框架(plug-and-play,PnP)与深度图像先验(deep image prior,DIP)的结合可实现CUP的低复杂度高保真图像重建,简称为PnP-DIP算法.PnP-DIP基于交替方向乘子法(alternating direction method of multipliers,ADMM),利用DIP和PnP去噪器解决图像恢复子问题,可以在防止数据过拟合和噪声累积的同时,显著提高图像重建的精度与收敛速度.通过数值模拟,我们理论上证明了PnP-DIP算法在重构原始动态信息方面相比传统ADMM算法具有更高的保真度.同时,我们分别利用PnPDIP对自主研制CUP系统观测的皮秒激光脉冲和X射线闪烁体的时空强度演化数据进行重构,实验上验证了其优越的图像重构性能.这一研究有望推动CUP在高时空分辨观测需求中的应用,并为超快动力学的实时探测作出重大贡献.

关键词：压缩超快成像图像重构交替方向乘子法即插即用深度图像先验

Nutrient resorption and stoichiometric responses of poplar(Populus deltoids)plantations to N addition in a coastal region of eastern China

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Journal of Plant Ecology 2021年第4期14卷 591-604页

作者： dalong Jiang Qian Li Qinghong Geng Menghua Zhang Chonghua Xu Guoqing Hu Caiqin shen Honghua Ruan Xia Xu Department of Ecology Co-Innovation Center for Sustainable Forestry in Southern ChinaNanjing Forestry UniversityNanjing210037China Advanced Analysis and Testing Center Nanjing Forestry UniversityNanjing 210037China College of Resources and Environment Shandong Agricultural UniversityTai’an 271018China Dongtai Forest Farm Yancheng 224200China

Aims Leaf nutrient resorption is sensitive to changes in soil ***,the effects of N deposition on nutrient resorption efficiency(NuRE)in plant macro-nutrients remain ***(Populus deltoids)is one of the most extensively cultivated hardwood species *** explored general patterns and dominant drivers of NuRE and stoichiometry of poplar plantations in response to N *** We conducted a 4-year N-addition experiment to explore NuRE and stoichiometric responses to N addition in two poplar(***)plantations(8-and 12-year-old stands)in a coastal region of eastern *** measured soil and foliar(green and senesced leaves)concentrations of nitrogen(N),phosphorus(P),potassium(K),calcium(Ca)and magnesium(Mg)for a series of N addition treatments including N_(0)(0 kg N ha^(−1)yr^(−1)),N_(1)(50 kg N ha^(−1)yr^(−1)),N_(2)(100 kg N ha^(−1)yr^(−1)),N_(3)(150 kg N ha^(−1)yr^(−1))and N_(4)(300 kg N ha^(−1)yr^(−1)).Important Findings Consistent for(both)8-and 12-year-old stands,N addition did not affect the NuRE and stoichiometry(with the exception of CaRE and CaRE:MgRE ratio).N resorption efficiency–P resorption efficiency(NRE–PRE)scaling slopes were consistently less than 1.0 under N *** results suggest that NRE generally decouples from PRE within each N ***,these results point to robust control of green leaf nutritional status on nutrient resorption processes as indicated by the positive relationships between NuRE and green leaf nutrient *** findings provided a direct evidence that growth in 12-year-old poplar plantations was N-limited in the coastal region of eastern China.

关键词： nutrient resorption efficiency N addition stoichiometry macro-nutrient green leaf nutrients poplar plantation

Correlation between magnetic resonance T2 image signal intensity ratio and cell apoptosis in a rabbit spinal cord cervical myelopathy model

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Chinese Medical Journal 2014年第2期127卷 305-313页

作者： Ma Lei Zhang Di Chen Wei shen Yong Zhang Yingze Ding Wenyuan Zhang Wei Wang Linfeng Yang dalong Department of Spinal Surgery Third Hospital of Hebei Medical University Orthopaedic Biomechanics Laborafory of Hebei Province Shijiazhuang Hebei 050051 China

Background Cervical spondylotic myelopathy （CSM） is a common cause of disability in elderly *** studies have shown that spinal cord cell apoptosis due to spinal cord compression plays an important role in the pathology of *** changes in magnetic resonance imaging （MRI） T2 signal intensity ratio （SIR） are considered to be an indicator of CSM,little information is published supporting the correlation between changes in MRI signal and pathological *** study aims to testify the correlation between MRI T2 SIR changes and cell apoptosis using a CSM animal *** Forty-eight rabbits were randomly assigned to four groups：one control group and three experimental chronic compression groups,with each group containing 12 *** compression of the cervical spinal cord was implemented in the experimental groups by implanting a screw in the C3 *** control group underwent sham *** groups were observed for 3,6,or 9 months after *** T2-weighted SIR Tarlov motor scores and cortical somatosensory-evoked potentials （CSEPs） were periodically *** each time point,rabbits from one group were sacrificed to determine the level of apoptosis by histology （n=6） and Western blotting （n=6）.Results Tarlov motor scores in the compression groups were lower at all time points than the control group scores,with the lowest score at 9 months （P ＜0.001）.Electrophysiological testing showed a significantly prolonged latency in CSEP in the compression groups compared with the control *** rabbits in the compression groups showed higher MRI T2 SIR in the injury epicenter compared with controls,and higher SIR was also found at 9 months compared with 3 or 6 *** analysis showed significant apoptosis in the spinal cord tissue in the compression groups,but not in the control *** were significant differences in apoptosis degree over time （P ＜0.001）,with the 9-month group displaying the most

关键词： cervical myelopathy model apoptosis magnetic resonance imaging T2 signal intensity ratio compression

Geometric structure of N_(2)O^(q+)(q=5,6)studied by Ne^(8+)ion-induced Coulomb explosion imaging

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Chinese Physics B 2021年第11期30卷 309-317页

作者： Xi Zhao Xu Shan Xiaolong Zhu Lei Chen Zhenjie shen Wentian Feng dalong Guo Dongmei Zhao Ruitian Zhang Yong Gao Zhongkui Huang Shaofeng Zhang Xinwen Ma Xiangjun Chen Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics University of Science and Technology of ChinaHefei 230026China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China

We report the study on the complete three-body Coulomb explosion(CE)of N_(2)O^(q+)(q=5,6)induced by 56-keV/u Ne8+ion collision with N2O gaseous *** CE channels for N_(2)O^(5+)and seven for N_(2)O^(6+)are identified by measuring three ionic fragments and the charge-changed projectile in quadruple *** the kinetic energy release(KER)and momentum correlation angle(MCA)distributions of three ionic fragments for each of the CE channels are also *** computation is presented to reconstruct the geometric structure of N_(2)O^(q+0prior to dissociation based on the measured KER and *** N–N and N–O bond lengths and the N–N–O bond angles of N_(2)O^(q+)for each of the channels are determined.

关键词： Coulomb explosion kinetic energy release molecular geometry ion collision nitrous oxide(N_(2)O)

Evaluation of NBI absorption and fast ion stored energy to improve thermal energy confinement time calculation in EAST

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Plasma Science and Technology 2020年第2期22卷 54-59页

作者： Xiang GU Biao shen Jinping QIAN Siye DING Hongfei DU Youwen SUN Bingjia XIAO Bin WU Jinfang WANG Juan HUANG Jiale CHEN Kai LI Guoqiang LI dalong CHEN Shuliang CHEN Muquan WU Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People's Republic of China University of Science and Technology of China Hefei 230026People's Republic of China

The absorption of neutral beam power and the fast ion stored energy in EAST plasmas with neutral beam injection(NBI)is analyzed to improve the calculation of thermal energy confinement *** neutral beam power absorption and fast ion stored energy are systematically calculated using the TRANSP code,through the investigation of global parameters including plasma current,line averaged density and beam *** have shown that scaling laws for the NBI absorption coefficient and fast ion energy rate are obtained through statistical analysis.A comparison of the confinement improvement factor H98y2 with these new scaling laws against those assuming fixed coefficients is given.

关键词： thermal energy confinement time neutral beam absorption fast ion energy