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Communications in Theoretical Physics 2006年第4期45卷 641-646页

作者： xu rui-rui chen tian-lun gao cheng-feng Department of Physics Nankai University Tianjin 300071 China

Nonlinear time series prediction is studied by using an improved least squares support vector machine （LSSVM） regression based on chaotic mutation evolutionary programming （CMEP） approach for parameter optimization. We analyze how the prediction error varies with different parameters （σ, γ） in LS-SVM. In order to select appropriate parameters for the prediction model, we employ CMEP algorithm. Finally, Nasdaq stock data are predicted by using this LS-SVM regression based on CMEP, and satisfactory results are obtained.

关键词： nonlinear time series prediction least squares support vector machine chaotic mutation evolu tionary programming

Application of deep learning methods combined with physical background in wide field of view imaging atmospheric Cherenkov telescopes

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Nuclear Science and Techniques 2024年第4期35卷 208-220页

作者： Ao-Yan cheng Hao Cai Shi chen tian-Lu chen Xiang Dong You-Liang feng Qi gao Quan-Bu Gou Yi-Qing Guo Hong-Bo Hu Ming-Ming Kang Hai-Jin Li chen Liu Mao-Yuan Liu Wei Liu Fang-Sheng Min Chu-cheng Pan Bing-Qiang Qiao Xiang-Li Qian Hui-Ying Sun Yu-Chang Sun Ao-Bo Wang xu Wang Zhen Wang Guang-Guang Xin Yu-Hua Yao Qiang Yuan Yi Zhang School of Physics and Technology Wuhan UniversityWuhan 430072China School of Physics and Astronomy Yunnan UniversityKunming 650091China Ministry of Education The Key Laboratory of Cosmic Rays(Tibet University)Lhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences 19 A Yuquan RoadShijingshan DistrictBeijing 100049China College of Physics Sichuan UniversityChengdu 610064China School of Intelligent Engineering Shandong Management UniversityJinan 250357China Tsung‑Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China Suzhou Aerospace Information Research Institute Suzhou 215123China College of Physics Chongqing UniversityNo.55 Daxuecheng South RoadHigh‑tech DistrictChongqing 401331China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210008China

The High Altitude Detection of Astronomical Radiation(HADAR)experiment,which was constructed in Tibet,China,combines the wide-angle advantages of traditional EAS array detectors with the high-sensitivity advantages of focused Cherenkov *** objective is to observe transient sources such as gamma-ray bursts and the counterparts of gravitational *** study aims to utilize the latest AI technology to enhance the sensitivity of HADAR *** datasets and models with distinctive creativity were constructed by incorporating the relevant physical theories for various *** models can determine the type,energy,and direction of the incident particles after careful *** obtained a background identification accuracy of 98.6%,a relative energy reconstruction error of 10.0%,and an angular resolution of 0.22°in a test dataset at 10 *** findings demonstrate the significant potential for enhancing the precision and dependability of detector data analysis in astrophysical *** using deep learning techniques,the HADAR experiment’s observational sensitivity to the Crab Nebula has surpassed that of MAGIC and *** energies below 0.5 TeV and remains competitive with conventional narrow-field Cherenkov telescopes at higher *** addition,our experiment offers a new approach for dealing with strongly connected,scattered data.

关键词： VHE gamma-ray astronomy HADAR Deep learning Convolutional neural networks

Discussion of Some Problems About Nonlinear Time Series Prediction Using v-Support Vector Machine

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Communications in Theoretical Physics 2007年第7期48卷 117-124页

作者： gao cheng-feng chen tian-lun NAN tian-Shi Department of Physics,Nankai University,tianjin 300071,China Department of Physics Nankai University Tianjin 300071 China

Some problems in using v-support vector machine(v-SVM)for the prediction of nonlinear time series *** problems include selection of various net parameters,which affect the performance of prediction,mixtureof kernels,and decomposition cooperation linear programming v-SVM regression,which result in improvements of *** simulations in the prediction of nonlinear time series produced by Mackey-Glass equation andLorenz equation provide some improved results.

关键词： v-SVM nonlinear time series prediction

Spectrally multiplexed and bright entangled photon pairs in a lithium niobate microresonator

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Science China(Physics,Mechanics & Astronomy) 2022年第9期65卷 3-9页

作者： Bo-Yu xu Li-Kun chen Jin-tian Lin Lan-tian feng rui Niu Zhi-Yuan Zhou Ren-Hong gao Chun-Hua Dong Guang-Can Guo Qi-Huang Gong Ya cheng Yun-feng Xiao Xi-feng Ren CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China State Key Laboratory of High Field Laser Physics and CAS Center for Excellence in Ultra-intense Laser Science Shanghai Institute of Optics and Fine Mechanics(SIOM)Chinese Academy of Sciences(CAS)Shanghai 201800China CAS Synergetic Innovation Center of Quantum Information&Quantum Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

On-chip bright quantum sources with multiplexing ability are extremely high in demand for integrated quantum networks with unprecedented scalability and ***,we demonstrate a bright and broadband biphoton quantum source with spectral multiplexing generated in a lithium niobate microresonator *** introducing the conventional domain poling,the on-chip microdisk produces photon pairs covering a broad bandwidth promised by natural phase matching in spontaneous parametric down ***,the multiplexed photon pairs are characterized by 30 nm bandwidth limited by the filtering system,providing over 40 multiplexing channels with a 0.8 nm channel ***,the generation rate reaches 5.13 MHz/μW with a coincidence-to-accidental ratio up to 804,and the quantum source manifests a high purity with a heralded single photon correlation g^((2))_(H)(0)=0.0098±***,the energy-time entanglement is demonstrated with an excellent interference visibility of 96.5%±2%.Such a quantum source at the telecommunication band paves the way for high-dimensional entanglement and future integrated quantum information systems.

关键词： quantum entangled source spectral multiplexing lithium niobate on insulator microresonator

小叶买麻藤茎化学成分及其黄嘌呤氧化酶抑制活性研究

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中成药 2024年第9期46卷 2994-2999页

作者：陈倩张正宽骆田田曾爱芬徐国波朱勤凤廖尚高贵州医科大学药学院/省部共建药用植物功效与利用国家重点实验室贵州贵阳550025 教育部民族药与中药开发应用工程研究中心/贵州省药物制剂重点实验室贵州贵阳550025

目的研究小叶买麻藤Gnetum parvifolium(Warb.)*** ex Chun茎的化学成分及其黄嘌呤氧化酶抑制活性。方法小叶买麻藤茎95%乙醇提取物采用硅胶、MCI、制备HPLC进行分离纯化,根据理化性质及波谱数据鉴定所得化合物的结构。采用紫外分光光... 详细信息

目的研究小叶买麻藤Gnetum parvifolium(Warb.)*** ex Chun茎的化学成分及其黄嘌呤氧化酶抑制活性。方法小叶买麻藤茎95%乙醇提取物采用硅胶、MCI、制备HPLC进行分离纯化,根据理化性质及波谱数据鉴定所得化合物的结构。采用紫外分光光度法测定黄嘌呤氧化酶的抑制活性。结果从中分离得到17个化合物,分别鉴定为异单叶大黄素(1)、白藜芦醇(2)、对羟基苯甲醛(3)、环桉树醇(4)、(E)-1-(3′,5′-dimethoxyphenyl)-2-(3,4-dimethoxyphenyl)ethene(5)、豆甾-4-烯-3-酮(6)、medioresinol(7)、白杨素(8)、金色酰胺醇酯(9)、(-)-松脂醇(10)、对羟基苯甲酸酯(11)、2-甲氧基对苯二酚(12)、gnetumontain C(13)、丁香脂素(14)、高圣草素(15)、香草醛(16)、β-谷甾醇(17)。化合物1~3、15~16的IC_(50)值分别为(11.4±0.54)、(14.1±1.06)、(320.4±0.75)、(360.6±0.78)、(386.3±0.71)μmol/L。结论化合物3~4为首次从该植物中分离得到,化合物5~13为首次从买麻藤属植物中分离得到。化合物1~3、15~16具有黄嘌呤氧化酶抑制活性。

关键词：小叶买麻藤茎化学成分分离鉴定黄嘌呤氧化酶

Cellular automata simulation of grain growth of powder metallurgy Ni-based superalloy

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Journal of Iron and Steel Research International 2023年第4期30卷 838-848页

作者： Yi-ling Jiang Sha-sha Liu Rong-gui Lu xu cheng Jia Li Yang chen gao-feng tian School of Materials Science and Engineering Beihang UniversityBeijing 100191China National Engineering Laboratory of Additive Manufacturing for Large Metallic Components Beijing 100191China Beijing Institute of Aeronautical Materials Beijing 100095China

Primary γ'phase instead of carbides and borides plays an important role in suppressing grain growth during solution at 1433 K of Ni-based FGH98 *** illustrate that as-fabricated FGH98 superalloy has equiaxed grain structure,and after heat treatment,grains remain equiaxed but grow *** order to clarify the effects of the size and volume fraction of the primaryγ'phase on the grain growth during heat treatment,a 2D cellular automata(CA)model was established based on the thermal activation and the lowest energy *** CA results are compared with the experimental results and show a good fit with an error less than 10%.Grain growth kinetics are depicted,and simulations in real time for various sizes and volume fractions of primaryγ'particles work out well with the Zener *** coefficient n value which reflects the pinning ability in Zener relation is theoretically calculated,and its minimum value is 0.23 when the radius of primaryγ'phase is 2.8μm.

关键词： Grain growth Cellular automata Ni-based FGH98 superalloy Primary γ'phase Microstructure

维普期刊数据库评论

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罕见的胃底腺型胃癌69例内镜特征分析

临床消化病杂志 2024年第3期36卷 168-171页

作者：文峰周昊程建国朱杰伦陈兰徐维田中部战区总医院消化科湖北武汉430010 江汉大学附属武汉市六医院湖北武汉430015

[目的]分析罕见的胃底腺型胃癌(GA-FG)内镜下特征,提高其诊治能力。[方法]在中国知网、万方医学、PubMed、Springer等数据库中检索相关文献,收集我国学者公开报道的GA-FG病例共68例(69处病灶),分别对“病变部位、大小、表面形态、色调... 详细信息

[目的]分析罕见的胃底腺型胃癌(GA-FG)内镜下特征,提高其诊治能力。[方法]在中国知网、万方医学、PubMed、Springer等数据库中检索相关文献,收集我国学者公开报道的GA-FG病例共68例(69处病灶),分别对“病变部位、大小、表面形态、色调、背景黏膜”等内镜下表现进行归纳,分析其内镜下主要形态特征。[结果]GA-FG好发于中老年,我国平均患病年龄59岁,无明显性别差异。98.6%病灶发生于胃中、上部,97.0%为单发病灶,96.0%无萎缩肠化背景黏膜,88.0%病灶小于1 cm,平均直径7.5 mm。79.7%病灶为隆起型,且以浅表隆起型(Ⅱa)占绝大多数。73.9%病灶表面有血管扩张。52.8%呈褪色调改变。[结论]发生于胃中上部、单个小于1 cm、无萎缩肠化背景黏膜、有表面血管扩张、呈褪色调改变的浅表隆起型病变是国内患者GA-FG内镜下主要形态特征。

关键词：胃癌胃底腺型内镜特征

In situ mitigation strategies for field emission-induced cavity faults using low-level radiofrequency system

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Nuclear Science and Techniques 2022年第11期33卷 46-60页

作者： feng Qiu Yuan He An-Dong Wu Zhen-Long Zhu Guo-Dong Jiang tian-Cai Jiang Zheng gao Qi chen Zong-Heng xue Jin-Ying Ma cheng-Ye xu Zi-Qin Yang Gui-Rong Huang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

In the Chinese ADS front-end demo superconducting radiofrequency linac(CAFe)at the Institute of Modern Physics,a burst-noise signal-triggered cavity fault frequently appears during beam *** events are characterized by a rapid burst noise in the cavity pick-up,which may lead to an unexpected low-level radiofrequency(LLRF)response that eventually causes a cavity *** eliminate the undesirable reaction of the LLRF control loop,we propose a method that uses a burstnoise detection and processing algorithm integrated into the LLRF feedback *** algorithm can prevent undesired regulations in LLRF *** analysis revealed that some burst-noise events did not exhibit measurable energy *** contrast,the other events were accompanied by a rapid loss of cavity stored energy and exhibited similarities to the‘‘E-quench’’phenomena reported in other laboratories.A particle-in-cell simulation indicated that the suspected E-quench phenomenon may be related to a plasma formation process inside the ***,the LLRF algorithm is robust to the two different types of burst-noise events and can significantly mitigate the corresponding cavity faults in CAFe beam commissioning.

关键词： Field emission Flashover E-quench Superconducting LLRF CAFe Plasma formation

Precise calibration of cavity forward and reflected signals using low-level radio-frequency system

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Nuclear Science and Techniques 2022年第1期33卷 35-43页

作者： Jin-Ying Ma feng Qiu Long-Bo Shi Zheng-Long Zhu tian-Cai Jiang Zong-Heng xue Ke-An Jin Qi chen cheng-Ye xu Xing-Hao Ding Zheng gao Lie-Peng Sun Gui-Rong Huang Yuan He Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Precise measurements of the cavity forward(Vf)and reflected signals(Vr)are essential for characterizing other key parameters such as the cavity detuning and forward *** practice,it is challenging to measure V_(f) and V_(r) precisely because of cross talk between the forward and reflected channels(e.g.,coupling between the cavity reflected and forward signals in a directional coupler with limited directivity).For DESY,a method based on the cavity differential equation was proposed to precisely calibrate the actual V_(f) and V_(r).In this study,we verified the validity and practicability of this approach for the Chinese ADS front-end demo superconducting linac(CAFe)facility at the Institute of Modern Physics and a compact energy recovery linac(cERL)test machine at *** the CAFe facility,we successfully calibrated the actual V_(f) signal using this *** result demonstrated that the directivity of directional couplers might seriously affect the accuracy of V_(f) *** the cERL facility,we calibrated the Lorentz force detuning(LFD)using the actual *** study confirmed that the precise calibration of V_(f) significantly improves the accuracy of the cavity LFD measurement.

关键词： Forward and reflected signals Measurement Calibration

CEPC Technical Design Report

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Radiation Detection Technology and Methods 2024年第1期8卷 I0003-I0016,1-1091页

作者： Waleed Abdallah Tiago Carlos Adorno de Freitas Konstantin Afanaciev Shakeel Ahmad Ijaz Ahmed Xiaocong Ai Abid Aleem Wolfgang Altmannshofer Fabio Alves Weiming An rui An Daniele Paolo Anderle Stefan Antusch Yasuo Arai Andrej Arbuzov Abdesslam Arhrib Mustafa Ashry Sha Bai Yu Bai Yang Bai Vipul Bairathi Csaba Balazs Philip Bambade Yong Ban Tripamo Bandyopadhyay Shou-Shan Bao Desmond P.Barber Ayse Bat Varvara Batozskaya Subash Chandra Behera Alexander Belyaev Michele Bertucci Xiao-Jun Bi Yuanjie Bi tianjian Bian Fabrizio Bianchi Thomas Biekotter Michela Biglietti Shalva Bilanishvili Deng Binglin Denis Bodrov Anton Bogomyagkov Serge Bondarenko Stewart Boogert Maarten Boonekamp Marcello Borri Angelo Bosotti Vincent Boudry Mohammed Boukidi Igor Boyko Ivanka Bozovic Giuseppe Bozzi Jean-Claude Brient Anastasiia Budzinskaya Masroor Bukhari Vladimir Bytev Giacomo Cacciapaglia Hua Cai Wenyong Cai Wujun Cai Yijian Cai Yizhou Cai Yuchen Cai Haiying Cai Huacheng Cai Lorenzo Calibbi Junsong Cang Guofu Cao Jianshe Cao Antoine Chance xuejun Chang Yue Chang Zhe Chang Xinyuan Chang Wei Chao Auttakit Chatrabhuti Yimin Che Yuzhi Che Bin chen Danping chen Fuqing chen Fusan chen Gang chen Guoming chen Hua-Xing chen Huirun chen Jinhui chen Ji-Yuan chen Kai chen Mali chen Mingjun chen Mingshui chen Ning chen Shanhong chen Shanzhen chen Shao-Long chen Shaomin chen Shiqiang chen tianlu chen Wei chen Xiang chen Xiaoyu chen Xin chen xun chen xurong chen Ye chen Ying chen Yukai chen Zelin chen Zilin chen Gang chen Boping chen Chunhui chen Hok Chuen cheng Huajie cheng Shan cheng Tongguang cheng Yunlong Chi Pietro Chimenti Wen Han Chiu Guk Cho Ming-Chung Chu Xiaotong Chu Ziliang Chu Guglielmo Coloretti Andreas Crivellin Hanhua Cui Xiaohao Cui Zhaoyuan Cui Brunella D'Anzi Ling-Yun Dai Xinchen Dai xuwen Dai Antonio De Maria Nicola De Filippis Christophe De La Taille Francesca De Mori Chiara De Sio Elisa Del Core Shuangxue Deng Wei-tian Deng Zhi Deng Ziyan Deng Bhupal Dev Tang Dewen Biagio Di Micco Ran Ding Siqin Dingl Yadong Ding Haiyi Dong Jianin AGH University of Science and Technology Faculty of Physics and Applied Computer ScienceKrakow Anhui University HefeiAnhui Applied Physics Department Federal Urdu University of ArtsScience and TechnologyIslamabad Banaras Hindu University Institute of ScienceVaranasi Bandirma Onyedi Eylul University Bandirma Beihang University Beijing Beijing Computational Science Research Center Beijing Beijing Conveyi LTD Beijing Beijing Glass Research Institute Co. LtdBeijing Beijing Institute of Technology Beijing Beijing Normal University Beijing Brown University ProvidenceRI Budker Institute of Nuclear Physics Novosibirsk Cadi Ayyad University Laboratory of Fundamental and Applied PhysicsPolydisciplinary FacultyMarrakech Cairo University Giza Center for Theory and Computation National Tsing Hua UniversityHsinchu Central China Normal University WuhanHubei Central South University ChangshaHunan Centro de Fisica Teorica de Particulas Universidade Tecnica de LisboaLisboa chengdu KaitengSifang Digital Radio&TV Equipment Co. LtdChengduSichuan China academy of engineering physics MianyangSichuan China building materials academy Beijing China Center of Advanced Science and Technology Beijing China Institute of Atomic Energy Beijing China Jiliang University HangzhouZhejiang China Nuclear Instrument CO. LTDBeijing China University of Geosciences Beijing China University of Geosciences WuhanHubei China University of Mining and Technology XuzhouJiangsu China West Normal University NanchongSichuan Chongqing University Department of PhysicsChongqing Chulalongkorn University Bangkok City University of Hong Kong Department of PhysicsHong Kong Cockcroft Institute Daresbury Cornell University IthacaNY CPPM(AMU/IPhU&CNRS/INP) Marseille Dalian Minzu University DalianLiaoning Dalian University of Technology Department of PhysicsDalian Deutsches Elektronen-Synchrotron DESY Hamburg Dzhelepov Laboratory of Nuclear Problems of Joint Institute for Nuclear Research(DLNP JINR) Dubna East China University Of Science And Technol

The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international *** complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs *** its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs *** the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of *** Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering ***,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection *** is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 *** commencement of experiments and data collection could potentially be initiated in the mid-2030s.

关键词： initiated exceeding precise