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Continuum estimation in low-resolution gamma-ray spectra based on deep learning

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Nuclear Science and Techniques 2025年第2期36卷 5-17页

作者： Ri zhao Li-Ye Liu Xin Liu zhao-xing Liu Run-Cheng Liang Ren-Jing Ling-Hu Jing Zhang Fa-Guo Chen China Institute for Radiation Protection Taiyuan 030006China Shanxi Provincial Key Laboratory for Translational Nuclear Medicine and Precision Protection Taiyuan 030006China

In this study,an end-to-end deep learning method is proposed to improve the accuracy of continuum estimation in low-resolution gamma-ray spectra.A novel process for generating the theoretical continuum of a simulated spectrum is established,and a convolutional neural network consisting of 51 layers and more than 105 parameters is constructed to directly predict the entire continuum from the extracted global spectrum *** testing,an in-house NaI-type whole-body counter is used,and 106 training spectrum samples(20%of which are reserved for testing)are generated using Monte Carlo *** addition,the existing fitting,step-type,and peak erosion methods are selected for *** proposed method exhibits excellent performance,as evidenced by its activity error distribution and the smallest mean activity error of 1.5%among the evaluated ***,a validation experiment is performed using a whole-body counter to analyze a human physical phantom containing four *** largest activity error of the proposed method is−5.1%,which is considerably smaller than those of the comparative methods,confirming the test *** multiscale feature extraction and nonlinear relation modeling in the proposed method establish a novel approach for accurate and convenient continuum estimation in a low-resolution gamma-ray ***,the proposed method is promising for accurate quantitative radioactivity analysis in practical applications.

关键词： Gamma-ray spectrum Continuum estimation Deep learning Convolutional neural network End-to-end prediction

前路人工椎体重建技术在骨水泥强化手术失败翻修病例中的应用

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中国骨伤 2025年第1期38卷 81-86页

作者：周一峰赵兴浙江大学医学院浙江杭州310000 浙江大学医学院附属邵逸夫医院骨科浙江杭州310016

目的:探讨前路伤椎次全切除、骨水泥清除、人工椎体植入、前路或后路内固定在骨质疏松骨折经骨水泥强化治疗失败后需要翻修的病例中的应用及体会。方法:从2020年1月至2021年12月,应用前路手术翻修治疗10例骨水泥强化治疗失败的患者,其中... 详细信息

目的:探讨前路伤椎次全切除、骨水泥清除、人工椎体植入、前路或后路内固定在骨质疏松骨折经骨水泥强化治疗失败后需要翻修的病例中的应用及体会。方法:从2020年1月至2021年12月,应用前路手术翻修治疗10例骨水泥强化治疗失败的患者,其中男2例,女8例;年龄55~83岁。翻修原因:术后感染2例,术后神经症状3例,术后椎体塌陷导致后凸畸形5例。其中L_(1)2例,L_(2)4例,L_(3)3例,L_(4)1例。初次经皮椎体成形术(percutaneous vertebroplasty,PVP)2例,经皮椎体后凸成形术(percutaneous kyphoplasty,PKP)8例。二次手术距离初次手术的时间为1~13个月。所有患者伴有不同程度的腰背部疼痛。翻修术前均行X线、CT和MRI检查。记录手术时间、术中出血、手术并发症、Oswestry功能障碍指数(Oswestry disability index,ODI)和疼痛视觉模拟评分(visual analogue scale,VAS)。结果:10例均成功施行手术,9例行前路重建+后路经多裂肌最长肌间隙内固定术;1例患者行前路重建+前路钢板内固定术。前路手术时间90~190 min,前路术中出血130~480 ml。所有患者未出现神经损伤、脑脊液漏、大血管损伤、腹腔脏器损伤、切口感染出血等术中及术后并发症。10例获得随访,时间3~20个月。随访期间,所有患者未出现人工椎体移位、切割、松动等并发症。VAS术前4~8分,末次随访2~3分;ODI评分术前17%~37%,末次随访2%~16%。5例后凸畸形翻修角度明显纠正。与手术前比较,VAS和ODI改善。结论:前路椎体次全切除、人工椎体植入,不仅可清除骨水泥,实现有效清创和直接减压;而且重建前中柱支撑,恢复椎体高度和局部曲度,结合椎弓根螺钉内固定,完成了手术节段的稳定性,因此对于骨水泥强化术失败需要翻修的患者,前路手术是一个理想的治疗选择。

关键词：前路重建人工椎体骨质疏松性骨折骨水泥强化翻修

沁水盆地MB区块山西组3~#煤层含气量及煤层气有利区预测

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大庆石油地质与开发 2025年第1期44卷 14-24页

作者：赵兴常锁亮曹文武梁可余攀张生幸晓凤山西山地物探技术有限公司山西晋中030600 太原理工大学地球科学与工程系山西太原030024 美中能源有限公司山西晋城048200

为明确沁水盆地MB区块山西组3^(#)煤层含气量及富集有利区,综合三维地震、测井和多种生产测试,在分析煤储层地球物理特征及含气地质控制作用的基础上,开展地质统计学反演、煤系沉积微相刻画及构造变形变位表征等研究,采用灰色关联分析构... 详细信息

为明确沁水盆地MB区块山西组3^(#)煤层含气量及富集有利区,综合三维地震、测井和多种生产测试,在分析煤储层地球物理特征及含气地质控制作用的基础上,开展地质统计学反演、煤系沉积微相刻画及构造变形变位表征等研究,采用灰色关联分析构建3^(#)煤层含气量预测模型,识别划分MB区块煤层气富集有利区。结果表明:研究区煤系地层砂岩与泥岩波阻抗差异小,通过伽马重构声波约束地质统计学反演能提高煤系地层砂岩、泥岩及煤层的识别精度;3^(#)煤层具有东厚西薄的分布特点,煤厚受沉积作用控制,厚煤层集中在北部、中东部的岸后沼泽区;3^(#)煤层含气量受埋藏深度、地层变形、煤厚和沉积环境等因素的控制,埋藏深度大、煤层厚且地层变形程度弱的东部区域整体含气量高,平均可达16 m^(3)/t,埋藏深度浅、煤层薄、地层陡倾且断裂发育的西部区域含气量较低,平均低于5 m^(3)/t;以煤层厚度、含气量为富集性评价参数,将研究区分为Ⅰ类有利区、Ⅱ类较有利区和Ⅲ类不利区,Ⅰ类有利区的煤层厚度为6~8 m,含气量为15.0~22.0 m^(3)/t;Ⅱ类较有利区的煤层厚度为3~6 m,含气量为10.0~15.0 m^(3)/t;Ⅲ类不利区的煤岩厚度和含气量分别小于3 m和10.0 m^(3)/t。研究成果可为MB区块煤层气的开发有利区优选提供理论指导。

关键词：煤层气控气地质因素含气性预测灰色关联法沁水盆地

Weak decays of heavy baryons in the light-front approach

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Chinese Physics C 2018年第9期42卷 1-14页

作者： Zhen-xing zhao INPAC.Shanghai Key Laboratory for Particle Physics and Cosmology MOE Key Lahoratory for Particle PhysicsAstrophysics and CosmologySchool of Physics and AstronomyShanghai Jiao-Tong UniversityShanghai 200240China

In this work, we analyse semi-leptonic and non-leptonic weak decays of the heavy baryons： Λ_b,Ξ_b,Ωb and Λ_c,Ξ_c,Ωc. For non-leptonic decay modes, we study only the factorizable channels induced by the external Wemission. The two spectator quarks in the baryonic transitions are treated as a diquark and form factors are calculated in the light-front approach. Using the results for form factors, we also calculate some corresponding semi-leptonic and non-leptonic decay widths. We find that our results are comparable with the available experimental data and other theoretical predictions. Decay branching fractions for many channels are found to reach the level 10^（-3）~10^（-2）,which is promising for discovery in future measurements at BESIII, LHCb and Belle II. The SU（3） symmetry in semi-leptonic decays is examined and sources of symmetry breaking are discussed.

关键词： heavy baryons weak decay light-front approach

Kinetics Investigation of Sintering of Nanometer Size Metal Clusters:A Molecular Dynamics Study

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Journal of Materials Science & Technology 2006年第1期22卷 123-126页

作者： xing zhao Shaoqing WANG Caibei ZHANG College of Science North-east-ern University Shenyang 110004 China Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China

The sintering process of nanometer size gold clusters is investigated by using molecular dynamics simulation in the frame of embedded atomistic method. Several molecular dynamics simulation techniques are used to observe and describe the evolution of the sintering process. The energy distribution for single cluster is examined and the snapshots of sintering process of two clusters are recorded. The evolution of sintering is also described by plotting the mass center changes with time for each cluster. The variations of kinetic and potential energy during the process of sintering are monitored and measured to analyze the dominant mechanisms of sintering from the energy point of view.

关键词： Sintering Nanometer size cluster Molecular dynamics

德国应用科学大学招生制度改革的动因、经验和启示

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职业教育研究 2025年第2期 84-89页

作者：董照星袁潇冯谱西南大学重庆400100 重庆师范大学重庆401331 重庆外语外事学院重庆401120

德国应用科学大学招生制度改革对德国技术技能人才的培养具有重要意义,促进了生源结构从“多而全”走向“专而精”,报考要求从“单一”走向“多元”,评价标准从“公平”走向“效率”,招生监管从“共治”走向“自治”。借鉴德国经验,我... 详细信息

德国应用科学大学招生制度改革对德国技术技能人才的培养具有重要意义,促进了生源结构从“多而全”走向“专而精”,报考要求从“单一”走向“多元”,评价标准从“公平”走向“效率”,招生监管从“共治”走向“自治”。借鉴德国经验,我国高等职业教育招生制度应该“以教促考”,加强育人与招生的联系;法定技能经验准入,制定适宜的招生条件;合理配置招生名额,提升“学生—学校—专业”的匹配度;完善相关考试法,保证院校招生自主权。

关键词：德国应用科学大学招生制度应用性

Effects of electric/magnetic impact on the transient fracture of interface crack in piezoelectric-piezomagnetic sandwich structure: anti-plane case

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Applied Mathematics and Mechanics(English Edition) 2020年第1期41卷 139-156页

作者： xing zhao Zhenghua QIAN Jinxi LIU Cunfa GAO Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Mechanics and Control of Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

Due to the incompatibility of the interlaminar deformations,the interface debonding or cracking usually happens in a layered magnetoelectric(ME)structure under an applied *** this paper,the transient responses of the anti-plane interface cracks in piezoelectric(PE)-piezomagnetic(PM)sandwich structures are studied by the standard methods of the integral transform and singular integral *** on the numerical examples indicates that the PE-PM-PE structure under electric impact is more likely to fracture than the PM-PE-PM structure under a magnetic *** dynamic stress intensity factors(DSIFs)are more sensitive to the variation of the active layer *** effects of the material constants on the DSIFs are dependent on the roles played by PE and PM media during the deformation process.

关键词： piezoelectric(PE)-piezomagnetic(PM) sandwich structure interface crack transient response dynamic stress intensity factor(DSIF)

Iontronic components: From liquid- to solid-states

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Nano Research 2023年第12期16卷 13343-13357页

作者： Tao Xiao xing zhao Yuchun Zhang Yong Yan CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Chemistry and Biological Engineering University of Science and Technology BeijingBeijing 100083China

In modern electronics,the ionic charges have not occupied the same role as the electrons mainly because of their relatively low ***,these“slow”charge carriers contribute to brain computing with high efficiency and extremely low power *** by the“ionic”life,iontronic components have recently attracted considerable *** this review,we first introduce the progress of iontronic devices operating with the involvement of water,specifically,two types of systems—nanofluidic and ***,the issues and challenges within these liquid-state ionic devices are *** avoid the negative impact of water,we also propose two solid-state materials—ionogels and charged metal nanoparticles—to construct several basic ionic devices such as diodes and ***,we summarize this review and outlook the promising directions for the further developments of iontronic devices.

关键词： ionic charges liquid-/solid-state diode transistor

Gas–liquid mass transfer and flow phenomena in the Peirce–Smith converter: a water model study

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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 37-44页

作者： xing zhao Hong-liang zhao Li-feng Zhang Li-qiang Yang Institute of Process Engineering Chinese Academy of ScienceBeijing 100190China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Green Recycling and Extraction of Metal Beijing 100083China Chambishi Copper Smelter Ltd. Beijing Representative OfficeBeijing 100029China

A water model with a geometric similarity ratio of 1：5 was developed to investigate the gas-liquid mass transfer and flow charac- teristics in a Peirce-Smith converter. A gas mixture of CO2 and Ar was injected into a NaOH solution bath. The flow field, volumetric mass transfer coefficient per unit volume （Ak/V; where A is the contact area between phases, V is the volume, and k is the mass transfer coeffi- cient）, and gas utilization ratio （t/） were then measured at different gas flow rates and blow angles. The results showed that the flow field could be divided into five regions, i.e., injection, strong loop, weak loop, splashing, and dead zone. Whereas the Ak/V of the bath increased and then decreased with increasing gas flow rate, and n steadily increased. When the converter was rotated clockwise, both Ak/F and t/increased. However, the flow condition deteriorated when the gas flow rate and blow angle were drastically increased. Therefore, these para- meters must be controlled to optimal conditions. In the proposed model, the optimal gas flow rate and blow angle were 7.5 m3.h-1 and 10°, respectively.

关键词： Peirce-Smith converter water model mass transfer flow phenomena volumetric mass transfer coefficient