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Study of imaging unknown objects by cosmic-ray muons

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Radiation Detection Technology and Methods 2021年第2期5卷 192-199页

作者： Mengzhao Li Yuekun Heng Yifang Wang Kaile Wen zhiyan cai Xiaoyu Yang Zhi Wu Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Introduction Cosmic-ray muon imaging is a kind of nondestructive detection technology which can be used to detect unknown objects in geological exploration,civil engineering and nuclear safety.Transmission imaging and scattering tomography schemes are studied.Method The transmission scheme uses a multilayer detector to measure the direction of a cosmic-ray muon passing through an object.The scattering scheme involves placing two detectors upstream and downstream of the object to record the incident and exit directions of the muon passing through the object.The effect of the detector resolution on the imaging clarity of transmission imaging was studied.The applicable scenarios of the two schemes were analyzed.Results The results by calculating show that in the transmission imaging of a hundred-meter object,a spatial resolution of 2.5 m can be achieved,and Cu and Fe can be discriminated with a density difference of 1.1 g/cm3.Scattering tomography is mainly suitable for meter-level objects,which can detect 0.2 m chamber and distinguish 0.05 m heavy metal blocks in rock.

关键词： Cosmic-ray muon imaging Muon Tomography Nondestructive detection

不同贮藏条件下水酶法牡丹籽油的氧化稳定性与货架期预测

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中国油脂 2024年第6期49卷 112-116页

作者：荣菡蔡至彦邓晓彤甘露菁杨丹北京理工大学珠海学院材料与环境学院广东珠海519088 中粮营养健康研究院营养健康与食品安全北京市重点实验室北京102209

旨在为水酶法牡丹籽油的品质控制提供理论依据,探究不同贮藏条件下水酶法牡丹籽油的氧化稳定性,并对其货架期进行预测。采用Schaal烘箱模拟加速氧化法,探究了抗氧化剂、包装材料、温度对牡丹籽油过氧化值的影响,并进行了氧化动力学分析... 详细信息

旨在为水酶法牡丹籽油的品质控制提供理论依据,探究不同贮藏条件下水酶法牡丹籽油的氧化稳定性,并对其货架期进行预测。采用Schaal烘箱模拟加速氧化法,探究了抗氧化剂、包装材料、温度对牡丹籽油过氧化值的影响,并进行了氧化动力学分析,采用Arrhenius方程进行拟合,建立了水酶法牡丹籽油货架期预测模型。结果表明:不同抗氧化剂的抗氧化效果排序为0.01%柠檬酸+0.01%TBHQ>0.02%TBHQ>0.02%柠檬酸>0.2%γ-谷维素;包装材料的抗氧化效果排序为棕色PET瓶>棕色玻璃瓶>透明PET瓶>透明玻璃瓶;随着温度升高,牡丹籽油的过氧化值明显增加;建立的货架期预测模型预测牡丹籽油在10、20、30℃下的货架期分别为117、77、51d,其实测货架期分别为134、90、60d。综上,使用抗氧化剂、避光、低温均能有效延缓水酶法牡丹籽油的氧化进程,建立的水酶法牡丹籽油货架期预测模型准确率良好。

关键词：牡丹籽油水酶法氧化稳定性货架期预测

The measurement system of acrylic transmittance for the JUNO central detector

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Radiation Detection Technology and Methods 2020年第3期4卷 284-292页

作者： Xiaoyu Yang Nan Li Yuekun Heng Mengzhao Li zhiyan cai Xiaoyan Ma Xiaohui Qian Kaixi Huang Zhi Wu Wei He Yatian Pei Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Beijing 100049China University of Chinese Academy of Science Beijing 100049China

Background The Jiangmen Underground Neutrino Observatory(JUNO)has 20 kilo-ton liquid scintillator as target mass contained by a huge acrylic sphere to carry out the research on neutrino physics.Acrylic transmittance is considered as an important optical performance of the JUNO Central Detector as it has a direct relationship to the number of photons detected by the JUNO Central Detector and further affects the energy resolution of JUNO.Motivation The transmittance requirement of acrylic spherical panel for the JUNO Central Detector is exceeding 96%at the wavelength of 420 nm in ultrapure water and a specific measurement system was built and studied in Institute of High Energy Physics for this purpose,as the existing equipment cannot perform the sample test in the liquid and support the long sample length of 120 mm.Methods After improving the technology of thermoforming,the transmittances of the acrylic spherical panels meet the requirement of JUNO,which guarantees the batch production of acrylic panels on time.The design of the measurement system,the constitution of hardware,the development of control and data acquisition software are introduced,and the measurement uncertainty of the system and the transmittance results of the acrylic samples from the spherical panel are discussed in this article.

关键词： Acrylic Optics Transmittance measurement Central detector JUNO

Adaptive Barebones Salp Swarm Algorithm with Quasi-oppositional Learning for Medical Diagnosis Systems: A Comprehensive Analysis

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Journal of Bionic Engineering 2022年第1期19卷 240-256页

作者： Jianfu Xia Hongliang Zhang Rizeng Li zhiyan Wang Zhennao cai zhiyang Gu Huiling Chen Zhifang Pan Department of General Surgery The Second Affiliated Hospital of Shanghai University(Wenzhou Central Hospital)Wenzhou325000ZhejiangPeople’s Republic of China Soochow University SuzhouJiangsuPeople’s Republic of China Department of Computer Science and Artificial Intelligence Wenzhou UniversityWenzhou325035People’s Republic of China School of Artificial Intelligence Jilin International Studies UniversityChangchun130000People’s Republic of China Wenzhou Polytechnic Wenzhou325035People’s Republic of China The First Affiliated Hospital of Wenzhou Medical University Wenzhou325000People’s Republic of China

The Salp Swarm Algorithm(SSA)may have trouble in dropping into stagnation as a kind of swarm intelligence method.This paper developed an adaptive barebones salp swarm algorithm with quasi-oppositional-based learning to compensate for the above weakness called QBSSA.In the proposed QBSSA,an adaptive barebones strategy can help to reach both accurate convergence speed and high solution quality;quasi-oppositional-based learning can make the population away from traping into local optimal and expand the search space.To estimate the performance of the presented method,a series of tests are performed.Firstly,CEC 2017 benchmark test suit is used to test the ability to solve the high dimensional and multimodal problems;then,based on QBSSA,an improved Kernel Extreme Learning Machine(KELM)model,named QBSSA–KELM,is built to handle medical disease diagnosis problems.All the test results and discussions state clearly that the QBSSA is superior to and very competitive to all the compared algorithms on both convergence speed and solutions accuracy.

关键词： Salp swarm algorithm Bare bones Quasi-oppositional based learning Function optimizations Kernel extreme learning machine

Cosmic ray test for a compact Cherenkov T0 detector

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Radiation Detection Technology and Methods 2020年第1期4卷 92-96页

作者： zhiyan cai Zhi Wu Yuekun Heng Nan Li Fengjiao Luo Mengzhao Li Wenlu Wei Kaile Wen Xiaoyu Yang Meihang Xu Yu man Wang Baojun Yan Shulin Liu Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China Department of Physics Nanjing UniversityNanjing 210093China

Purpose A compact T0 detector with high time resolution is developed.Methods The T0 detector is based on a multi-anode MCP-PMT coupled with two fused quartzes.The characteristics of this MCP-PMT are studied by a fast laser pulse in laboratory firstly.Cosmic ray test has been carried out to study T0 detector's signal features and time resolution.Conclusions by off-line analysis The T0 detector's time resolution is less than 40 ps for the cosmic ray events.It can be applicable in cosmic ray test,beam test,collider experiment and detector developments.

关键词： TO detector Cherenkov MCP-PMT Time resolution

Laser measurement system for acrylic transmittance of JUNO central detector

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Radiation Detection Technology and Methods 2021年第3期5卷 356-363页

作者： Zhaohan Li Xiaoyu Yang Yuekun Heng Xiaoyan Ma Xiaohui Qian Kaixi Huang Zhi Wu Wei He Meihang Xu Xiaolan Luo Yatian Pei Mengzhao Li zhiyan cai Wenlu Wei Yifang Wang Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Beijing 100049China University of Chinese Academy of Science Beijing 100049China

Background During the research phase of acrylic panel for the Jiangmen Underground Neutrino Observatory(JUNO)central detector(CD),the darkroom transmittance measurement system(DTMS)was designed and built,and a massive amount of measurements were carried out to help determine the composition and processing techniques of the acrylic panel.Motivation The mass production of acrylic panels was started after the pilot production.The requirement of transmittance measurement put forward new demands on operation,and a new measurement system was considered to support removable and non-destructive measurement on site.Result After the accomplishment of design,development and verification were completed,the laser measurement system came into use in the acrylic workshop of Taixing Donchamp Acrylic Ltd,and the transmittance results of acrylic spherical panels met the requirement of JUNO.The optical design,tooling design,data processing interface and uncertainty analyses of the laser measurement system are discussed in detail,and the measured transmittance results are also introduced in this article.

关键词： Laser Non-destructive measurement Transmittance JUNO

CBL联合LBLm教学模式对神经内科临床规培教学中的应用效果分析

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医院与医学 2024年第1期12卷 23-27页

作者：蔡宏斌刘志艳刘沛田婷葛朝明兰州大学第二医院(第二临床医学院) 甘肃兰州730030

目的分析CBL联合LBLm教学模式对神经内科临床规培教学中的应用效果分析。方法选取兰州大学第二医院(第二临床医学院)住培学员100人,随机分为对照组(常规教学模式,n=50)和观察组(CBL+LBLm教学,n=50),对照组采用传统带教法,观察组采用CBL... 详细信息

目的分析CBL联合LBLm教学模式对神经内科临床规培教学中的应用效果分析。方法选取兰州大学第二医院(第二临床医学院)住培学员100人,随机分为对照组(常规教学模式,n=50)和观察组(CBL+LBLm教学,n=50),对照组采用传统带教法,观察组采用CBL联合LBLm教学模式,对比2组教学优劣。结果观察组各出科成绩高于对照组,差异具有统计学意义(P<0.05)。观察组住院医师满意度显著优于对照组,差异具有统计学意义(P<0.05)。结论在神经病学临床规培中采用CBL联合LBLm的教学模式教学,有利于提高规培医师的自学能力,提升医患沟通能力,加强其对理论知识的理解和系统运用,拓展临床思维、强化规培医师的临床诊疗和实践操作能力。

关键词： CBL LBLm教学神经内科规培教学

Study on acrylic transmittance for JUNO Central Detector

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Radiation Detection Technology and Methods 2021年第2期5卷 284-289页

作者： Xiaoyu Yang Nan Li Yuekun Heng Xiaohui Qian Xiaoyan Ma Yuesheng Tang Jianxia Xiao Gaofeng Zhang Wei Cheng Hongbing Song Mengzhao Li zhiyan cai Kaixi Huang Zhi Wu Wei He Yatian Pei Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Beijing 100049China University of Chinese Academy of Science Beijing 100049China TaixingDonchamp Acrylic Co. LtdTaixing 225400China Chengdu Tomny Innovation Tech.Co. LtdChengdu 610041China

Background The Central Detector(CD)of the Jiangmen Underground Neutrino Observatory(JUNO)uses 20,000 tons of liquid scintillator as target mass,and the design value of energy resolution of neutrino is 3%at 1 meV.Acrylic transmittance is an important parameter for CD in order to maximize the detection of scintillating photons.Motivation The composition and processing techniques of acrylic can surely affect its transmittance.How the composition,thermoforming temperature,heat preservation time and surface treatment process of acrylic affect its transmittance was measured and analyzed.Methods According to these studies,JUNO determined its special acrylic composition and processing techniques:no components of plasticizer or anti-UV in the composition,decreasing the time span and temperature during the demolding of flat panel,and adopting suitable thermoforming temperature of spherical panel.Results Finally,the preproduction of spherical acrylic panels meets the JUNO requirement confirming a transmittance in ultrapure water greater than 96%at the wavelength of 420 nm.

关键词： Acrylic Transmittance Central Detector JUNO

Thermal reliability analysis of the central detector of JUNO

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Radiation Detection Technology and Methods 2019年第4期3卷 51-60页

作者： Xiaoyu Yang Yuekun Heng Xiaoyan Ma Wei He Huafeng Li Kaixi Huang Tao Song Jiajie Ling Zhi Wu Xiao Tang Xiaolan Luo Xiaohui Qian Yatian Pei Nan Li Fengjiao Luo zhiyan cai Mengzhao Li Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Beijing 100049China University of Chinese Academy of Science Beijing 100049China Beijing Institute of Architectural Design Beijing 100045China China Academy of Building Research Beijing 100013China Sun Yat-Sen University Guangzhou 510275China

Introduction The Jiangmen Underground Neutrino Observatory(JUNO)is a multipurpose neutrino experiment designed to determine neutrino mass hierarchy,precisely measure oscillation parameters and study solar neutrinos,supernova neutrinos and geo-neutrinos,etc.The central detector(CD)of JUNO has 20,000 tons liquid scintillator as target mass,which contains inside a huge acrylic sphere with inner diameter of 35.4 m,supported by a stainless steel structure.The whole structure of CD will be installed inside a cylindrical water pool,and the acrylic sphere will be submerged in the center of water pool.The operating temperature of CD is designed to be 21℃ as long as over 20 years,which is determined by the mechanical requirement of the structure and physics consideration.Methods For this operating temperature,a special cooling system will be used to maintain the temperature inside the water pool.The main structure of CD is composed of acrylic and stainless steel,and they have much different thermal expansion coefficients,strengths and life times.Change in temperature may affect the safety of CD.As part of reliability analysis,the effect of cooling system failure on the CD is considered,and finite element method is used in our thermal calculation.In this article,the temperature fields before and after cooling system failure are calculated and analyzed,and the temperatures of different locations of water pool after cooling system failure are compared and discussed in detail.

关键词： Thermal analysis Finite element method Central detector JUNO