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D^(*) jet fragmentation function paradox and combination mechanism

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Communications in Theoretical Physics 2023年第2期75卷 80-88页

作者： Chuanhui Jiang Honglei li shi-yuan li Shufen liu Xinyue Yin School of Physics Shandong UniversityJinanShandong 250100China School of Physics and Technology University of JinanJinan Shandong 250022China Tai’an Eco-environmental Monitoring Station of Shandong Province Tai’an Shandong 271000China Department of Physics Chongqing UniversityChongqing 401331China

In the framework of the perturbative Quantum Chromodynamics factorization,the production of a hadron includes contributions from fragmentation as well as combination,with the latter being of higher *** particular,the heavy meson production can be via the combination of a heavy quark with a light one,and the cross section can be factorized to be the convolution of the combination matrix element,the light quark distribution function,and the hard partonic sub-cross section of the heavy quark *** partonic distribution and the combination matrix element are functions of a scaling variable,respectively,which is the momentum fraction of the corresponding quark with respect to the heavy *** studied the D^(*±)production in jet via combination in pp collision at the *** total result is comparable with the experimental *** combination matrix elements can be further studied in various hadron production processes.

关键词： D^(*)-jet,fragmentation function,combination mechanism

Chatter identification of thin-walled parts for intelligent manufacturing based on multi-signal processing

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Advances in Manufacturing 2021年第1期9卷 22-33页

作者： Dong-Dong li Wei-Min Zhang yuan-shi li Feng Xue Jürgen Fleischer School of Mechanical Engineering Tongji UniversityShanghai 201804People's Republic of China Bosch Rexroth Endowed Chair for Automation&Electrification Solutions Sino-German College for Postgraduate StudyTongji UniversityShanghai 201804People's Republic of China China North Engine Research Institute Tianjin 300400People's Republic of China WBK Institute of Production Science Karlsruhe Institute of TechnologyKarlsruhe 76131Germany

Machine chatter is still an unresolved and challenging issue in the milling process,and developing an online chatter identification and process monitoring system towards smart manufacturing is an urgent *** this paper,two indicators of chatter detection are *** is the real-time variance of milling force signals in the time domain,and the other one is the wavelet energy ratio of acceleration signals based on wavelet packet decomposition in the frequency ***,a novel classification concept for vibration condition,called slight chatter,is proposed and integrated successfully into the designed multi-classification support vector machine(SVM)***,a mapping model between image and chatter indicators is established via a distance threshold on the *** multi-SVM model is trained by the results of three signals as an *** data and detection accuracy of the SVM model are verified in actual *** identification accuracy of 96.66%has proved that the proposed solution is feasible and *** presented method can be used to select optimized milling parameters to improve machining process stability and strengthen manufacturing system monitoring.

关键词： Chatter Milling force Acceleration Wavelet packet decomposition Multi-sensor

Effects of supercritical CO_(2) on viscoelastic properties of shales

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Petroleum Science 2022年第5期19卷 2199-2209页

作者： Da-Wei Zhou Guang-Qing Zhang Zhong-Wei Huang shi-yuan li Zong-Yang Fan College of Petroleum Engineering China University of Petroleum in BeijingBeijing102249China State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum in BeijingBeijing102249China

Laboratory uniaxial compression creep tests,with differential stress of 30 MPa hold for 3 h,were performed on Chang-7,Longmaxi(LMX)and Barnett shales to study the influence of SC-CO_(2)on short-term viscoelastic *** this end,the wet shale samples were treated with SC-CO_(2)with a pressure of30 MPa and a temperature of 110℃for 14 *** analyzed the creep data using the fractional Maxwell *** investigate microscopic structural alterations,the surface morphology of the same location,before and after SC-CO_(2)-water exposure,was examined by SEM *** with dry shales,dynamic and static elastic moduli decreased by up to 25.02%and 55.83%,respectively,but the creep deformation increased by 200%for LMX and Chang-7 shales,and 500%for the Barnett shale treated by SC-CO_(2).Compared to dry sample,there is an increase in calculated fractional orders of 0.02,0.07,0.22 for SC-CO_(2)treated samples,indicating that SC-CO_(2)treatment is likely to enhance shale *** investigation confirmed physicochemical mechanisms responsible for the observed elastic damage and creep enhancement,including mineral dissolution and swelling caused by SC-CO_(2).This work would further improve our current understanding of the time-dependent deformation of shale under chemicalmechanical coupling effects during CO_(2)capture utilization and storage.

关键词： Shale creep Viscoelastic deformation SC-CO_(2)exposure Physicochemical mechanisms

AGC-ASC Synthetic Neural Net Control System in Rolling Process

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International Journal of Minerals,Metallurgy and Materials 1998年第2期12卷 108-112页

作者： Zhongsuo shi yuan li Yikang Sun Information Engineering School, UST Beijing, Beijing 100083, China Information Engineering School UST Beijing Beijing 100083 China

Automation Gauge Control(AGC) and Automatic Shape Control(ASC) are coupling each other. The coupling models of AGC-ASC synthetic system for the thickness-crown have been established and two artificial neural networks controllers are given. The simulation of computer shows that the AGC-ASC synthetic system can obtain the expected thickness and shape precision with both schemes.

关键词： neural network neural net controller AGC-ASC synthetic system

Precise evaluation of h→cc and axion-like particle production

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Chinese Physics C 2021年第9期45卷 65-72页

作者： shi-yuan li Zhen-Yang li Peng-Cheng Lu Zong-Guo Si School of Physics Shandong UniversityJinan 250100China

We study the decay of the SM Higgs boson to a massive charm quark pair at the next-to-next-to-leading order QCD and next-to-leading order *** the second order of QCD coupling,we consider the exact calculation of flavour-singlet contributions where the Higgs boson couples to the internal top and bottom *** information on the running mass effects related to Yukawa coupling may be obtained by analyzing this *** precision production for h→cc within the SM makes it possible to search for new physics that may induce relatively large interactions related to the charm *** an example,we evaluate the axion-like particle associate production with a charm quark pair in the Higgs decay and obtain some constraints for the corresponding parameters under some assumptions.

关键词： Higgs boson charm quark QCD axion-like particle

Production and constraints for a massive dark photon at electron-positron colliders

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Chinese Physics C 2020年第2期44卷 62-71页

作者： Jun Jiang Chun-yuan li shi-yuan li Shankar Dayal Pathak Zong-Guo Si Xing-Hua Yang School of Physics Shandong UniversityJinanShandong 250100China Department of Physics Lovely Professional UniversityPhagwaraPunjab144411India

Dark sector may couple to the Standard Model via one or more mediator *** discuss two types of mediators:the dark photon A’ and the dark scalar mediator Φ .The total cross-sections and various differential distributions of the processes e+e-→qqA’ and e+e→qqφ（q=u,d,c,s and b quarks） are *** focus on the study of the invisible due to the cleaner background at future e+*** is found that the kinematic distributions of the two-jet system could be used to identify（or exclude） the dark photon and the dark scalar mediator,as well as to distinguish between *** further study the possibility of a search for dark photons at a future CEPC experiment with s1/2=91.2 GeV and 240 *** CEPC running at s1/2=91.2 GeV,it would be possible to perform a decisive measurement of the dark photon（20 GeV limits of the integrated luminosity for the significance S/B1/2=2σ,3σ and 5σ are presented.

关键词： dark photon dark scalar mediator CEPC

Double-heavy tetraquark states with heavy diquark-antiquark symmetry

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Chinese Physics C 2021年第4期45卷 70-86页

作者： Jian-Bo Cheng shi-yuan li Yan-Rui liu Zong-Guo Si Tao Yao School of Physics Shandong UniversityJinan 250100China

We calculate the masses of the QQqq(Q=c,b:q=u,d,s)tetraquark states with the aid of heavy diquark-antiquark symmetry(HDAS)and the chromomagnetic interaction(CMI)*** masses of the highestspin(J=2)tetraquarks that have only the(QQ)(3):(qq)_(3).color structure are related with those of conventional hadrons using ***,the masses of their partner states are determined with the mass splittings in the CMI *** numerical results reveal that(i)the lightest ccnn(n=u,d)is an I(J^(P))=0(1^(+))state around 3929 MeV(53 MeV above the DD^(*) threshold),and none of the double-charm tetraquarks are stable;(ii)the stable double-bottom tetraquarks are the lowest 0(1^(+))bbin around 10488 MeV(≈116 MeV below the BB^(*)threshold)and the lowest 1/2(1^(+))bbns around 10671 MeV(≈20 MeV below the BB_(s)^(*)/B_(s)B^(*)threshold);and(iii)the two lowest bcnn tetraquarks,namely the lowest 0(0^(+))around 7167 MeV and the lowest 0(1)around 7223 MeV,are in the nearthreshold ***,we discuss the constraints on the masses of double-heavy ***,for the lowest nonstrange tetraquarks,we obtain T_(cc)<3965 MeV,T_(bb)<10627 MeV,and T_(bc)<7199 MeV.

关键词： heavy diquark-antiquark symmetry(HDAS) chromomagnetic interaction(CMI)model double-heavy tetraquark mass spectrum

Hidden-charm Pentaquark Production at e^(+)e^(-) Colliders

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Communications in Theoretical Physics 2018年第3期69卷 291-296页

作者： shi-yuan li Yan-Rui liu Yu-Nan liu Zong-Guo Si Xiao-Feng Zhang School of Physics Shandong UniversityJinan 250100China Institute of Theoretical Physics Chinese Academy of ScienceBeijing 100190China

We study one possible production mechanism for the hidden-charm pentaquark via a color-octet cc pair fragmentation in e^(+)e^(-)*** pentaquark production at B factory energy is dominated by e^(+)e^(-)→ccg→P_(c)+X,while at Z^(0)pole energy,there are several partonic processes playing significant *** results show that it is possible to search for the direct pentaquark production signal at e^(+)e^(-)colliders,which is important to understand the properties of pentaquark.

关键词： pentaquark e^(+)e^(-)annihialation NRQCD

Exotic hadron bound state production at hadron colliders

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Chinese Physics C 2017年第8期41卷 53-63页

作者： Yi Jin shi-yuan li Yan-Rui liu Lu Meng Zong-Guo Si Xiao-Feng Zhang School of Physics and Technology University of Jinan Jinan 250022 China School of Physics Shandong University Jinan 250100 China CCEPP Institute of High Energy Physics Beijing 100049 China

The non-relativistic wave function framework is applied to study the production and decay of exotic hadrons, which can be effectively described as bound states of other hadrons. Employing the factorized formulation,with the help of event generators, we investigate the production of exotic hadrons in multiproduction processes at high energy hadron colliders. This study provides crucial information for the measurements of the relevant exotic hadrons.

关键词： bound states of hadrons wave function multiproduction