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The study of intelligent algorithm in particle identification of heavy-ion collisions at low and intermediate energies
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作者 Gao-Yi Cheng Qian-Min Su +1 位作者 Xi-Guang Cao Guo-Qiang Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期170-182,共13页
Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate energies.Researchers urgently need solutions to the... Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate energies.Researchers urgently need solutions to the dilemma of traditional particle identification methods.This study explores the possibility of applying intelligent learning algorithms to the particle identification of heavy-ion collisions at low and intermediate energies.Multiple intelligent algorithms,including XgBoost and TabNet,were selected to test datasets from the neutron ion multi-detector for reaction-oriented dynamics(NIMROD-ISiS)and Geant4 simulation.Tree-based machine learning algorithms and deep learning algorithms e.g.TabNet show excellent performance and generalization ability.Adding additional data features besides energy deposition can improve the algorithm’s performance when the data distribution is nonuniform.Intelligent learning algorithms can be applied to solve the particle identification problem in heavy-ion collisions at low and intermediate energies. 展开更多
关键词 heavy-ion collisions at low and intermediate energies Machine learning Ensemble learning algorithm Particle identification Data imbalance
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Calculation of depth-dose distribution of intermediate energy heavy-ion beams 被引量:3
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作者 Qiang Li Zengquan Wei Wenjian Li 《Chinese Science Bulletin》 SCIE EI CAS 2002年第20期1708-1710,共3页
Based on the characteristics of the interactions between intermediate energy heavy-ion beam and target matter, a method to calculate the depth-dose distribution of heavy-ion beams with intermediate energy (10-100 MeV/... Based on the characteristics of the interactions between intermediate energy heavy-ion beam and target matter, a method to calculate the depth-dose distribution of heavy-ion beams with intermediate energy (10-100 MeV/u) is presented. By comparing high energy beams where projectile fragmentation is overwhelming with low energies where energy straggling is the sole factor instead, a crescent energy spread with increasing depth and a simple fragmentation assumption were included for the depth-dose calculation of the intermediate energy beam. Relative depth-dose curves of carbon and oxygen ion beams with intermediate energies were computed according to the method here. Comparisons between the calculated relative doses and measurements are shown. The calculated Bragg curves, especially the upstream and downstream Bragg peaks, agree with the measured data. Differences between the two results appear only around the peak regions because of the limitations of the calculation and experimental conditions, but the 展开更多
关键词 intermediate energy heavy-ion beam depth-dose distri-bution energy STRAGGLING primary beam attenuation projectile fragmentation.
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Determining the nuclear temperature dependence on source neutron-proton asymmetry in heavy-ion reactions at intermediate energy
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作者 曲国峰 黄宇 +9 位作者 郑华 刘星泉 R.Wada 林炜平 黄美容 韩纪锋 任培培 杨振雷 张鑫 冷强钟 《Chinese Physics C》 SCIE CAS CSCD 2023年第5期152-159,共8页
In this article,we investigate the dependence of nuclear temperature on emitting source neutron-proton(N/Z)asymmetry with light charged particles(LCPs)and intermediate mass fragments(IMFs)generated from intermediate-v... In this article,we investigate the dependence of nuclear temperature on emitting source neutron-proton(N/Z)asymmetry with light charged particles(LCPs)and intermediate mass fragments(IMFs)generated from intermediate-velocity sources in thirteen reaction systems with different N/Z asymmetries,^(64)Zn on^(112)Sn,and^(70)Zn,^(64)Ni on^(112,124)Sn,^(58,64)Ni,^(197)Au,and^(232)Th at 40 MeV/nucleon.The apparent temperature values of LCPs and IMFs from different systems are deduced from the measured yields using two helium-related and eight carbon-related double isotope ratio thermometers,respectively.Then,the sequential decay effect on the experimental apparent temperature deduction with the double isotope ratio thermometers is quantitatively corrected explicitly with the aid of the quantum statistical model.The present treatment is an improvement compared to our previous studies in which an indirect method was adopted to qualitatively consider the sequential decay effect.A negligible N/Z asymmetry dependence of the real temperature after the correction is quantitatively addressed in heavy-ion reactions at the present intermediate energy,where a change of o.1 units in source N/Z asymmetry corresponds to an absolute change in temperature of an order of 0.03 to 0.29 MeV on average for LCPs and IMFs.This conclusion is in close agreement with that inferred qualitatively via the indirect method in our previous studies. 展开更多
关键词 nuclear temperature N/Z asymmetry dependence Albergo thermometer sequential decay correction heavy-ion reactions at intermediate energy
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过渡材料在高能束流连接钛钢中的应用 被引量:2
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作者 李洪强 彭勇 +3 位作者 周琦 樊新民 郭顺 章王威 《电焊机》 2017年第11期27-30,共4页
钛与钢的连接既能满足性能要求又能降低成本,因此钛钢焊接受到了广泛关注。鉴于它们的物理性能差异较大,直接连接的强度特别低甚至完全开裂,因此增加中间过渡材料的方法成为研究热点。高能束流特别是激光和电子束具有能量密度高和焊接... 钛与钢的连接既能满足性能要求又能降低成本,因此钛钢焊接受到了广泛关注。鉴于它们的物理性能差异较大,直接连接的强度特别低甚至完全开裂,因此增加中间过渡材料的方法成为研究热点。高能束流特别是激光和电子束具有能量密度高和焊接熔宽窄的特点,对焊接钛钢具有一定优势。综述了高能束流连接钛钢接头时所添加的过渡材料的种类和应用情况。 展开更多
关键词 钛合金 中间过渡材料 应用情况 高能束流
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中间梁方式下压电式能量采集器发电性能研究 被引量:3
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作者 闫晓东 周公博 《电子学报》 EI CAS CSCD 北大核心 2022年第2期404-414,共11页
压电式能量采集器(Piezoelectric Energy Harvester,PEH)固定方式的改变会直接影响其发电性能,而传统悬臂梁固定方式(Cantilever Beam Fixed Mode,CBFM)调频范围窄且发电性能较差.为了使PEH的发电性能最大化,提出了一种适用于任意尺寸... 压电式能量采集器(Piezoelectric Energy Harvester,PEH)固定方式的改变会直接影响其发电性能,而传统悬臂梁固定方式(Cantilever Beam Fixed Mode,CBFM)调频范围窄且发电性能较差.为了使PEH的发电性能最大化,提出了一种适用于任意尺寸压电片的中间梁固定方式(Intermediate Beam Fixed Mode,IBFM).同时,通过仿真和实验的方法研究了添加不同质量块后CBFM和IBFM两种固定方式的发电性能.结果表明,在相交频带处,与CBFM相比,采用IBFM后,PEH在单位加速度条件下最大开路电压和发电功率分别平均提升了95.19%和205.88%.此外,机电耦合系数(Electromechanical coupling coefficient,EMCC)平均提升了11.60%.因此,所提出的方法可以为PEH在不同频段处固定方式的选择提供指导. 展开更多
关键词 压电式能量采集器 发电性能 悬臂梁固定方式 中间梁固定方式 相交频带
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中能重离子束深度剂量分布计算 被引量:4
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作者 李强 卫增泉 李文建 《高能物理与核物理》 EI CSCD 北大核心 2000年第5期414-417,共4页
提出了称之为复合歧离算法的中能重离子束深度剂量分布计算方法 ,并计算了中能C ,O离子束的Bragg相对剂量分布曲线 ,同实验测量结果进行了比较 ,计算与实验测量符合得很好 .证实了复合歧离算法的合理性及由它计算Bragg曲线的可靠性 .
关键词 中能重离子束 深度剂量 能量歧离
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三段式可更换耗能梁抗震性能及可更换性能分析 被引量:2
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作者 门进杰 范栋鑫 +2 位作者 邓德平 王家琛 张谦 《建筑结构学报》 EI CAS CSCD 北大核心 2023年第1期57-67,共11页
为了保证框架结构跨度较大时耗能梁的耗能能力和可更换性能,提出了一种中间段耗能的三段式可更换耗能钢梁。设计并制作了5根可更换耗能钢梁,通过拟静力试验,研究了耗能梁更换、耗能段与非耗能段连接方式、耗能段腹板类型及腹板钢材类型... 为了保证框架结构跨度较大时耗能梁的耗能能力和可更换性能,提出了一种中间段耗能的三段式可更换耗能钢梁。设计并制作了5根可更换耗能钢梁,通过拟静力试验,研究了耗能梁更换、耗能段与非耗能段连接方式、耗能段腹板类型及腹板钢材类型等对钢梁抗震性能的影响。研究结果表明:在地震作用下,三段式可更换耗能钢梁的耗能和损伤均明显集中在中间耗能段,而非耗能段处于弹性状态,震后通过更换中间受损耗能段即可快速恢复结构的使用功能;三段式可更换耗能钢梁的滞回曲线均较饱满,极限塑性转角约为0.1 rad,表现出良好的变形能力和耗能能力;腹板采用低屈服点钢或波纹钢时三段式可更换耗能钢梁的耗能能力更好;随着可更换钢梁塑性转角的增大,可更换耗能钢梁的荷载提高明显,超强系数均值约为1.67;更换耗能段时,相应的层间位移角为1/200~1/250,采用端板连接的三段式可更换耗能钢梁更换耗能段所需时间较短,而采用双槽钢连接的三段式可更换耗能钢梁能在更大的残余层间位移角时更换,具有较优的可更换性能。 展开更多
关键词 可更换耗能钢梁 中间耗能段 拟静力试验 抗震性能 可更换性能 塑性转角 残余层间位移角
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在HIRFL上的中能重离子物理基础和应用研究 被引量:2
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作者 罗亦孝 《核物理动态》 CSCD 1992年第3期19-27,共9页
本文总结了三年来在兰州重离子研究装置(HIRFL)上进行的科研工作和取得的成果.简单介绍了HIRFL 的工作状态、次级束流线与ECR 离子源的发展、中能重离子引起的反应研究、热核与远离β稳定线核素的合成与研究和重离子束的应用等.
关键词 HIRFL 次级束流 热核 中能重离子
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