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搜索域维度扩展稳健匹配场声源辐射功率估计

西北工业大学学报 2024年第1期42卷 1-10页

作者：张少东孙超西北工业大学航海学院陕西西安710072 陕西省水下信息技术重点实验室陕西西安710072 西北工业大学青岛研究院山东青岛266200

与传统声源辐射功率估计方法相比,匹配场声源辐射功率估计方法能获得更准确的估计结果,但环境失配对其性能影响较大。针对这一问题,提出一种搜索域维度扩展稳健匹配场声源辐射功率估计方法。定义环境失配影响因子,量化表示环境失配对信... 详细信息

与传统声源辐射功率估计方法相比,匹配场声源辐射功率估计方法能获得更准确的估计结果,但环境失配对其性能影响较大。针对这一问题,提出一种搜索域维度扩展稳健匹配场声源辐射功率估计方法。定义环境失配影响因子,量化表示环境失配对信道传递函数和匹配场声源辐射功率估计方法的影响,确定提升环境失配稳健性的关键在于准确估计信道传递函数。传统匹配场声源辐射功率估计方法中信道传递函数搜索域是一个距离-深度二维平面,环境失配时,其中必然不包含真实信道传递函数,因此信道传递函数估计结果与真实信道传递函数也必然存在偏差。文中提出的搜索域维度扩展稳健匹配场声源辐射功率估计方法将信道传递函数搜索域扩展为距离、深度和不确定参数组构成的三维搜索空间,将真实信道传递函数包含在搜索域中,使得最优备选信道传递函数等于真实信道传递函数。随后构造三维搜索空间的目标函数,目标函数的绝对值越小,备选信道传递函数与真实信道传递函数偏差越小。使用目标函数绝对值取最小值时对应的备选信道传递函数可以更准确地估计声源辐射功率,仿真验证了理论分析的结果。

关键词：声源辐射功率估计搜索域维度扩展环境失配稳健性

基于液闪EJ301研制的中子探测器的性能测试

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核技术 2024年第8期47卷 59-66页

作者：张少东金宝亮张小东华北电力大学北京102206 深圳市核与辐射安全重点实验室中国核能与安全高等研究院深圳大学物理与光电工程学院深圳518060

随着核能和核技术的飞速发展,特种殊核材料的应用越来越广泛,为了提高核材料监测能力,基于液闪探测器的核材料无损检测技术得到了广泛的研究。基于液体闪烁体EJ301,自主设计研制了灵敏体积为直径7.62 cm、厚度5.08 cm的液体闪烁体探测器... 详细信息

随着核能和核技术的飞速发展,特种殊核材料的应用越来越广泛,为了提高核材料监测能力,基于液闪探测器的核材料无损检测技术得到了广泛的研究。基于液体闪烁体EJ301,自主设计研制了灵敏体积为直径7.62 cm、厚度5.08 cm的液体闪烁体探测器,并对该液体闪烁体探测器的中子/伽马(n/γ)甄别性能进行了测试。首先,使用22Na和60Co γ源对探测器进行能量刻度;然后,使用252Cf中子源对探测器的n/γ甄别性能进行测试,并基于电荷比较法计算出不同能量阈值下的FOM(Figure of Merit)值,并与Eljen公司的EJ301和Saint-Gobain的BC501A液体闪烁体探测器就n/γ甄别性能进行了比较;最后,使用飞行时间法对液体闪烁体探测器的绝对n/γ甄别性能进行了评价。测试结果表明:自主研发的液体闪烁体探测器的n/γ甄别性能略优于Eljen公司的EJ301和Saint-Gobain的BC501A液体闪烁体探测器;在能量阈值为150 keV时,利用飞行时间法作为n/γ甄别的绝对标准,测试得到自主研发的探测器在使用电荷比较法时的伽马误甄率别仅为万分之一。

关键词：液体闪烁体探测器能量刻度中子/伽马甄别电荷比较法飞行时间法

What Can Topology Bring to Chemistry?

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CCS Chemistry 2024年第9期6卷 2084-2109页

作者： Wei Wang Songtao Zhou Xiujun Yu Qing-Hui Guo Yanhang Ma Jie Song Liang zhang Xuzhou Yan Lu Han Qing Liao Xiaopeng Li Wen-Bin zhang Yiyong Mai shaodong zhang Shunai Che Hai-Bo Yang Xuefeng Fu Mei-Xiang Wang School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200062 Hangzhou Institute of Medicine Chinese Academy of SciencesHangzhou 310022Zhejiang College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060Guangdong MOE Key Laboratory of Bioorganic Phosphorous and Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084 School of Physical Science and Technology and Shanghai Key Laboratory of High-Resolution Electron Microscopy ShanghaiTech UniversityShanghai 201210 School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesState Key Laboratory of Composite MaterialsShanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai 200240 School of Chemical Science and Engineering Tongji UniversityShanghai 200092 Beijing Key Laboratory for Optical Materials and Photonic Devices Department of ChemistryCapital Normal UniversityBeijing 100048 Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871 Department of Chemical Sciences National Natural Science Foundation of ChinaBeijing 10085

The unique mathematical perspectives and principal concepts of topology have not only promoted the development of other branches of mathematics but have also deeply influenced other subjects,particularly physics and *** minireview aims to elucidate the substantial influence of topology on chemistry by critically examining both the contributions of topology to current chemical science and its potential future *** will discuss the topology of molecular structures and assemblies across various scales—from small molecules and mechanically interlocked molecules to polymers,biomacromolecules,and supramolecular *** discussion will include an exploration of cutting-edge techniques for characterizing topological features,underscoring the role of topology as a novel paradigm for the design and synthesis of new molecular ***,a critical analysis of topology’s role in the development of functional materials—such as photonic materials,polymers,biomacromolecules,and chiral materials—will demonstrate its emerging significance as a crucial parameter in unveiling novel properties and *** topology’s formidable potential,it is anticipated to be used increasingly to address pivotal challenges within chemistry and adjacent disciplines.

关键词： chemical topology topological invariants molecular graphs links and knots structureproperty relationship

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一种液体闪烁体探测器的结构优化

核电子学与探测技术 2024年第5期44卷 891-896页

作者：金宝亮马麟张少东张小东华北电力大学核科学与工程学院北京102206 深圳市核与辐射安全重点实验室深圳518060 中国核能与安全高等研究院深圳518060 深圳大学物理与光电工程学院深圳518060

本文详述了自主研发的一种新型液体闪烁体探测器。该探测器的灵敏体积由一个圆柱体和一个圆台拼接而成,因此使得最大直径为3 in的液体闪烁体可以通过圆台能够与1.5 in光电倍增管进行直接对接,无需额外光导。为了选取圆台的最佳倾斜角度... 详细信息

本文详述了自主研发的一种新型液体闪烁体探测器。该探测器的灵敏体积由一个圆柱体和一个圆台拼接而成,因此使得最大直径为3 in的液体闪烁体可以通过圆台能够与1.5 in光电倍增管进行直接对接,无需额外光导。为了选取圆台的最佳倾斜角度,首先利用Geant4模拟软件对不同圆台倾斜角度的探测器光收集效率进行模拟,然后制作角度分别为30°、45°和60°的探测器进行最佳角度的实验验证。实验首先使用22Na和60Coγ源对探测器进行能量刻度并进行光收集效率对比,在误差范围内实验测得的光收集效率随角度的变化规律与模拟结果基本一致,即随着斜面角度的增大,光的收集效率逐渐增高,并且随着角度增大光收集效率的增加越来越快。然后使用252Cf中子源对其中子γ甄别性能进行测试,并基于电荷比较法计算出相同能量阈值下的FOM(Figure of Merit)值,计算结果表明,随着液闪探测器光收集效率的提升,其中子γ甄别性能也得到增强。

关键词：液体闪烁体探测器 n/γ甄别结构优化

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我国废弃油脂回收利用现状及产业化分析

中国油脂 2024年第8期49卷 97-102页

作者：敬加强丁庆薇罗双子依吴承轩张少冬西南石油大学石油与天然气工程学院成都610500 四川省油气消防重点实验室成都610500 西南财经大学国际商学院成都611130

为保障公众饮食安全和促进废弃油脂资源的合理利用,通过相关文献的系统调研与全面分析,结合专家咨询与实地考察,系统分析我国废弃油脂回收利用技术发展现状、产业化竞争优势及面临的挑战,并提出产业化建议。我国对废弃油脂的回收利用技... 详细信息

为保障公众饮食安全和促进废弃油脂资源的合理利用,通过相关文献的系统调研与全面分析,结合专家咨询与实地考察,系统分析我国废弃油脂回收利用技术发展现状、产业化竞争优势及面临的挑战,并提出产业化建议。我国对废弃油脂的回收利用技术研究与成果转化非常活跃,已形成产业化。我国废弃油脂回收利用产业化具有市场规模大、能源转型与环保需求高、国家政策支持等竞争优势,但目前仍存在废弃油脂集运、处理技术及管理水平低,加工技术与管理水平不足,产品质量与利用水平有待提升等问题。从建立企业认证规范,统筹废弃油脂回收监督,加快产业技术创新,激发公众主体意识等方面提出了产业化发展的建议。综上,我国废弃油脂回收利用产业发展前景广阔,但仍面临较大挑战,亟待政府、高校、企业及公众共同努力推动废弃油脂回收利用的产业化发展。

关键词：废弃油脂回收利用发展现状竞争优势产业化建议

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A topographic parameter inversion method based on laser altimetry

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Science China(Technological Sciences) 2012年第5期55卷 1273-1280页

作者： HUANG ChunMing zhang shaodong CHEN Xi School of Electronic Information Wuhan UniversityWuhan 430079China Key Laboratory of Geospace Environment and Geodesy Ministry of EducationWuhan 430079China State Observatory for Atmospheric Remote Sensing Wuhan 430079China

A topographic parameter inversion method based on laser altimetry is developed in this paper, which can be used to deduce the surface vertical profile and retrieve the topographic parameters within the laser footprints by analyzing and simulating return waveforms. This method comprises three steps. The first step is to build the numerical models for the whole measuring procedure of laser altimetry, construct digital elevation models for surfaces with different topographic parameters, and calculate return waveforms. The second step is to analyze the simulated return waveforms to obtain their characteristics parameters, summarize the effects of the topographic parameter variations on the characteristic parameters of simulated return waveforms, and analyze the observed return waveforms of laser altimeters to acquire their characteristic parameters at the same time. The last step is to match the characteristic parameters of the simulated and observed return waveforms, and deduce the topographic parameters within the laser footprint. This method can be used to retrieve the topographic parameters within the laser footprint from the observed return waveforms of spaceborne laser altimeters and to get knowledge about the surface altitude distribution within the laser footprint other than only getting the height of the surface encountered firstly by the laser beam, which extends laser altimeters' function and makes them more like radars.

关键词： Laser altimetry return waveform simulation Gaussian fitting topographic parameter inversion

平流层爆发性增温期间中高层大气行星波研究进展

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地球与行星物理论评（中英文） 2024年第1期55卷 109-119页

作者：马铮龚韵张绍东武汉大学电子信息学院武汉430072 贵州师范大学贵阳550001

极区平流层爆发性增温(SSW)是冬季半球最剧烈的大气扰动现象之一.SSW期间温度和风场的剧烈变化被认为是冬季半球中高层大气波动能量异常增强的主要原因.流星雷达是能够稳定连续探测中间层和低热层风场的重要地基探测设备.主要依托国家... 详细信息

极区平流层爆发性增温(SSW)是冬季半球最剧烈的大气扰动现象之一.SSW期间温度和风场的剧烈变化被认为是冬季半球中高层大气波动能量异常增强的主要原因.流星雷达是能够稳定连续探测中间层和低热层风场的重要地基探测设备.主要依托国家重大科技基础设施建设项目:“子午工程”,我国已建设了多个流星雷达观测台站,对中间层和低热层风场进行了长期稳定连续的监测,为揭示SSW期间中间层和低热层波动异常变化的物理机制提供了重要的观测资料.本文简述了近年来以我国“子午工程”流星雷达监测数据为核心,SSW期间中高层大气行星波的研究进展和成果;深入讨论了冬季半球中高层大气行星波发生异常变化的主要激发机制.随着“子午工程”二期十个流星雷达台站即将建成,本文对利用“子午工程”流星雷达监测台网进一步研究SSW期间中高层大气波动的变化特性进行了展望.

关键词：平流层爆发性增温子午工程流星雷达大气行星波

Anomalous changes of temperature and ozone QBOs in 2015−2017 from radiosonde observation and MERRA-2 reanalysis

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Earth and Planetary Physics 2021年第3期5卷 280-289页

作者： XiaoYan Bai KaiMing Huang shaodong zhang ChunMing Huang Yun Gong School of Electronic Information Wuhan UniversityWuhan 430072China Key Laboratory of Geospace Environment and Geodesy Ministry of EducationWuhan 430072China State Observatory for Atmospheric Remote Sensing Wuhan 430072China

Anomalous changes of zonal wind quasi-biennial oscillation(QBO)in winter 2015−2016 have received close *** radiosonde and satellite observations and reanalysis data,we investigate anomalous changes in temperature and ozone QBOs from the lower to middle *** wind shear direction is reversed due to unexpected changes of zonal wind QBO at about 24−30 km,the shortest cold phase at 21−27 km appears in temperature *** is different from the completely interrupted westward phase in zonal wind QBO,while the longest cold phase above almost 27 km lasts for 2−3 years from 2015 to 2017,owing to the absence of corresponding warm *** scale reduction of temperature QBO causes a small temperature anomaly,thus the thermal wind relationship looks seemingly different from that in the other regular QBO *** in the ozone mixing ratio anomaly shows a double-peak with inverse phase,and its phase below(above)30 km is in agreement with(opposite to)the phase of temperature QBO because of different control mechanisms of *** temperature QBO variation,QBO in the ozone mixing ratio anomaly exhibits a less positive phase at 20−30 km in 2016−2017,and a very long positive phase above 30 km from 2015 to *** in total column ozone shows a small peak in winter 2016−2017 since ozone is mainly concentrated at 20 to 30 *** changes of temperature and ozone QBOs due to unexpected QBO zonal wind variation can be well-explained according to thermal wind balance and thermodynamic balance.

关键词： QBO temperature anomaly ozone anomaly thermal wind balance

Simulation of the equatorial quasi-biennial oscillation based on the parameterization of continuously spectral gravity waves

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Chinese Science Bulletin 2009年第2期54卷 288-295页

作者： HUANG KaiMing zhang shaodong ,YI Fan CHEN ZeYu School of Electronic Information Wuhan University Wuhan 430079 China Key Laboratory of Geospace Environment and Geodesy Ministry of Education Wuhan 430079 China State Observatory for Atmospheric Remote Sensing Wuhan 430079 China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

On the basis of previous parameterization schemes, considering both the wave breaking and absorbed at critical level, a parameterization with a continuous spectrum of gravity waves is realized by introducing a momentum flux density function for the wave spectrum, and then the parameterization scheme of the gravity waves is improved. Choosing parameter values of the background atmosphere and waves based on the observations, a more realistic equatorial quasi-biennial oscillation (QBO) driven by the incorporated drag from the planetary and gravity waves can be simulated. The numerical results indicate that the forcing magnitude of the planetary and gravity waves varies with the wind field, and in some phases of the QBO, the contribution of the gravity waves is comparable with that of the planetary waves. After the QBO is steadily formed, its amplitude and period and wind configuration are relevant to the effect of vertical diffusion and the momentum flux distribution with spectrum, however, independent of the initial background wind field. Moreover, for any given nonzero initial background wind, a steady QBO can be finally generated due to the incorporated drag from the planetary and gravity waves.

关键词：大气科学重力波中间层低热层大气环流