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Communications in Theoretical Physics 2024年第1期76卷 1-6页

作者： Engui Fan yanxi zhang School of Mathematical Sciences and Key Laboratory of Mathematics for Nonlinear Science Fudan UniversityShanghai200433China Tianjin Xinhua High School No.99 machang RoadTianjin300204China

In this paper,we address interesting soliton resolution,asymptotic stability of N-soliton solutions and the Painleve asymptotics for the Kundu-Eckhaus(KE)equation with nonzero boundary conditions iq_(t)+q_(xx)-2(l|q|^(2)-1)q+4β^(2)(lql^(4)-1)q+4iβ(lql^(2))_(x)q=0,q(x,0)=q_(0)(x)-±1,x→±∞.The key to proving these results is to establish the formulation of a Riemann-Hilbert(RH)problem associated with the above Cauchy problem and find its connection with the RH problem of the defocusing NLS *** the■-steepest descent method and the results of the defocusing NLS equation,we find complete leading order approximation formulas for the defocusing KE equation on the whole(x,t)half-plane including soliton resolution and asymptotic stability of N-soliton solutions in a solitonic region,Zakharov-Shabat asymptotics in a solitonless region and the Painlevéasymptotics in two transition regions.

关键词： defocusing Kundu-Eckhaus equation Riemann-Hilbert problems steepest descent method soliton resolution asymptotic stability Painleve transcendents

Online Monitoring of Welding Status Based on a DBN Model During Laser Welding

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Engineering 2019年第4期5卷 671-678页

作者： yanxi zhang Deyong You Xiangdong Gao Seiji Katayama Guangdong Provincial Welding Engineering Technology Research Center Guangdong University of TechnologyGuangzhou 510006China Joining and Welding Research Institute Osaka UniversityOsaka 567-0047Japan

In this research,an auxiliary illumination visual sensor system,an ultraviolet/visible(UVV)band visual sensor system(with a wavelength less than 780 nm),a spectrometer,and a photodiode are employed to capture insights into the high-power disc laser welding *** features of the visible optical light signal and the reflected laser light signal are extracted by decomposing the original signal captured by the photodiode via the wavelet packet decomposition(WPD)*** captured signals of the spectrometer mainly have a wavelength of 400-900 nm,and are divided into 25 sub-bands to extract the spectrum features by statistical *** features of the plume and spatters are acquired by images captured by the UVV visual sensor system,and the features of the keyhole are extracted from images captured by the auxiliary illumination visual sensor *** on these real-time quantized features of the welding process,a deep belief network(DBN)is established to monitor the welding status.A genetic algorithm is applied to optimize the parameters of the proposed DBN *** established DBN model shows higher accuracy and robustness in monitoring welding status in comparison with a traditional back-propagation neural network(BPNN)*** effectiveness and generalization ability of the proposed DBN are validated by three additional experiments with different welding parameters.

关键词： Online monitoring Multiple sensors Wavelet packet decomposition Deep belief network

Detecting the single chiral molecule during the reaction

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Science China Materials 2023年第8期66卷 3377-3378页

作者： Juejun Wang Zepeng zhang Shurui Ji yanxi zhang Wenjing Hong College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005China The Institute of Flexible Electronics(IFE Future Technologies)Xiamen UniversityXiamen 361005China

Detecting an individual molecule during the chemistry dynamics is essential for capturing accurate information about the chemical process in the time domain,which could be achieved by precisely forming single-molecule junctions between two electrodes and reading out the variation in electrical signals[1–3],but has yet to penetrate the stereochemistry *** is a crucial pursuit of chirality chemistry to develop effective asymmetric synthesis methodologies and reveal the physicochemical mechanisms[4,5].And the key obstacle lies in achieving in situ detection of chiral intermediates in reactions[6].Chirality is a fundamental molecular property arising from the structure asymmetry,with two mirror-image forms known as *** to similar signals of enantiomeric isomers,it is a great challenge to distinguish chiral species and the process of their configurational transformation in single-molecule *** then comes up with a question—how to detect chirality changes in stereochemistry.

关键词： chiral isomers mirror

Heavy flavour physics and CP violation at LHCb:Aten-year review

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Frontiers of physics 2023年第4期18卷 1-69页

作者： Shanzhen Chen Yiming Li Wenbin Qian Zhihong Shen Yuehong Xie Zhenwei Yang Liming zhang yanxi zhang Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Nuclear Physics and Technology&School of Physics Peking UniversityBeijing 100871China Key Laboratory of Quark and Lepton Physics of Ministry of Education&Institute of Particle Physics Central China Normal UniversityWuhan 430079China Department of Engineering Physics&Center for High Energy Physics Tsinghua UniversityBeijing 100084China

Heavy flavour physics provides excellent opportunities to indirectly search for new physics at very high energy scales and to study hadron properties for deep understanding of the strong *** LHCb experiment has been playing a leading role in the study of heavy flavour physics since the start of the LHC operations about ten years ago,and made a range of high-precision measurements and unexpected discoveries,which may have far-reaching implications on the field of particle *** review highlights a selection of the most influential physics results on CP violation,rare decays,and heavy flavour production and spectroscopy obtained by LHCb using the data collected during the first two operation periods of the *** upgrade plan of LHCb and the physics prospects are also briefly discussed.

关键词： LHCb flavour physics CP vioation

The Structure and Size-effect of Calcium Modified Lead Titanate Nanocrystal,Pb_(0.85)Ca_(0.15)TiO_3

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Chemical Research in Chinese Universities 1999年第2期15卷 66-70页

作者： FU Honggang QIANG Liangsheng XU Chongquan ZHAN Zhiqian zhang Xin YU Haitao zhang yanxi HUANG Li Department of Applied Chemistry Harbin University of TechnologyHarbin150001 School of Chemistry and Engineering Heilongjiang UniversityHa rbin150080 La b.of Enha nce d Oil Recovery Rate of Institution of E.and D. Daqing163712

Calcium modified lead titanate nanocrystal material Pb0.85Ca0.15TiO3 was synthesized by means of a solgel *** changes of crystal structure and grainsize of the samples were investigated under different conditions of heat *** results show that the tetragonal symmetry is reduced and the ferroelectricparaelectric phase transformation temperature is decreased with the reduce of the grainsize of the *** critical grainsize for the ferroelectricparaelectric phase transformation at room temperature was *** change regularities of the lattice constant and tetragonality with the grainsize are discussed.

关键词： PTC15 Nanocrystal Crystal structure Size effect Crystal structure, Size effect

Computer-assisted preoperative planning for proximal humeral fractures by minimally invasive plate osteosynthesis

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Chinese Medical Journal 2014年第18期127卷 3278-3285页

作者： Chen yanxi zhang Kun Qiang Minfei Li Haobo Dai Hao Department of Orthopaedic Trauma East Hospital Tongji UniversitySchool of Medicine Shanghai 200120 China

Background Accurate and precise preoperative planning can provide information instrumental for performing less invasive articular fracture surgery. The purpose of this study was to determine that computer-assisted preoperative planning （CAPP） has the potential to improve efficiency and time in the operating room. Methods Sixty-four patients with proximal humeral fractures were treated using locking plates by minimally invasive plate osteosynthesis （MIPO） with CAPP. The time needed for virtual segmentation, reduction, and fixation of the fracture fragments were recorded. Intra and interobserver reliabilities were analyzed using the intraclass correlation coefficient. The clinical function was analyzed using Constant Score and radiology. Results The mean total time required for CAPP of two-part, three-part, and four-part proximal humeral fractures were （13.63±1.38） minutes, （23.14±2.18） minutes, and （39.61±3.01） minutes, respectively. The intra and interobserver reliabilities for all variables were high, ranging from 0.785 to 0.992. The mean operation time was （50.1±6.7） minutes. Fifty- two patients were followed up with an average time of 34.2 months. The mean Constant Score of the injury side was （82.5 ± 9.9）. Three of the fifty-two patients had four complications. Conclusion The application of CAPP was efficient and reliable, and provided excellent clinical and radiographic outcomes for the treatment of proximal humerus fractures by MIPO.

关键词： proximal humerus fractures computer-aided design preoperative planning minimally invasive plate osteosynthesis imaging, three-dimensional

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1973:作家路遥的高考

南方文坛 2021年第1期 117-121页

作者：张艳茜陕西省社会科学院文学所

路遥是新时期有重大影响的作家,他的作品丰富了我们的文学宝库,感染了无数的读者。从青年农民王卫国到著名作家路遥,路遥走过的是坎坷的不平凡的人生之路。1966年初中毕业,本来想考中专的路遥(即当时的王卫国),赶上了“文化大革命”的爆... 详细信息

路遥是新时期有重大影响的作家,他的作品丰富了我们的文学宝库,感染了无数的读者。从青年农民王卫国到著名作家路遥,路遥走过的是坎坷的不平凡的人生之路。1966年初中毕业,本来想考中专的路遥(即当时的王卫国),赶上了“文化大革命”的爆发,路遥继续读书升学的梦想化为泡影。此时,时代好似为路遥提供了一条比读书升学更加快捷、轻松的道路——只要敢于造反,敢于冲锋陷阵,就可以前途无量。

关键词：路遥王卫国人生之路造反升学文化大革命读书作家

A scheme to fix multiple solutions in amplitude analyses

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Chinese Physics C 2024年第5期48卷 8-22页

作者：高原宁荣天泽杨振伟张辰佳张艳席 School of Physics Peking UniversityBeijing 100871China

Decays of unstable heavy particles usually involve the coherent sum of several amplitudes,like in a multiple slit *** amplitude analysis techniques have been widely used to resolve these amplitudes for better understanding of the underlying *** special cases where two spin-1/2 particles and two(pseudo-)scalar particles are present in the process,multiple equivalent solutions are found owing to intrinsic symmetries in the summed probability density *** this study,the problem of multiple solutions is discussed,and a scheme to overcome this problem is proposed by fixing some free *** are generated to validate the strategy.A new approach to align the helicities of initial-and final-state particles in different decay chains is also introduced.

关键词： amplitude analysis multiple solutions helicity formalism

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中国饲料 2000年第2期 2-3页

作者：张延喜中国饲料工业协会!副会长

在迎接新世纪,庆贺新千年的时候,饲料行业如同其他行业一样,也在筹划今后的发展问题.

关键词：农业饲料工业饲料业加工工业

激光电弧复合焊接顺序对304不锈钢T形接头影响的模拟试验分析

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焊接学报 2021年第12期42卷 34-39,I0002,I0003页

作者：桂晓燕张艳喜游德勇高向东广东工业大学广东省焊接工程技术研究中心广州510006

建立304不锈钢T形接头三维有限元模型,研究激光电弧复合焊接顺序对304不锈钢T形接头热变形及残余应力的影响.采用高斯面热源加高斯锥形体热源组合的热源模型,模拟激光电弧复合热源,并通过304不锈钢激光电弧复合堆焊工艺试验验证数值模... 详细信息

建立304不锈钢T形接头三维有限元模型,研究激光电弧复合焊接顺序对304不锈钢T形接头热变形及残余应力的影响.采用高斯面热源加高斯锥形体热源组合的热源模型,模拟激光电弧复合热源,并通过304不锈钢激光电弧复合堆焊工艺试验验证数值模拟激光电弧复合焊接过程的可靠性.结果表明,焊缝截面熔池形貌的数值仿真结果与焊接工艺试验结果吻合较好,该热源模型能有效模拟激光电弧两种热源的复合作用.确定多种焊接顺序方案,分析不同焊接顺序下T形接头温度场、残余应力和热变形情况,激光电弧复合焊接顺序对T形接头残余应力及热变形均有影响,通过对比不同顺序下残余应力值及热变形量发现,顺序焊接能有效减小焊接残余应力,同时反向焊接产生的热变形量最小.综合分析,不锈钢T形接头顺序反向焊接的效果最佳.

关键词：激光电弧复合焊接 304不锈钢T形接头焊接顺序数值模拟