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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

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

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

激光焊OCT熔深测量去噪及数据拟合方法研究

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激光技术 2024年第4期48卷 590-596页

作者：黄贻蔚高向东李来明马波张艳喜广东工业大学机电工程学院广东省焊接工程技术研究中心广州510006

为了解决激光焊接熔深在线检测及光学相干光层析成像(OCT)熔深检测信号噪声多的问题,采用了一种百分位滤波加移动平均算法的熔深曲线拟合方法。通过光学相干光层析成像系统对304不锈钢匙孔焊过程进行了熔深在线检测,在使用百分位滤波从... 详细信息

为了解决激光焊接熔深在线检测及光学相干光层析成像(OCT)熔深检测信号噪声多的问题,采用了一种百分位滤波加移动平均算法的熔深曲线拟合方法。通过光学相干光层析成像系统对304不锈钢匙孔焊过程进行了熔深在线检测,在使用百分位滤波从原始散点数据中提取出百分位熔深曲线过程中,发现该方法提取的百分位熔深曲线存在尖峰干扰噪声,通过移动平均算法对百分位熔深曲线进行低通滤波处理,最终从原始散点数据中提取拟合出OCT熔深测量曲线。结果表明,将OCT熔深测量曲线与焊缝纵抛面的实际熔深曲线进行对比,该方法获取OCT熔深测量曲线的测量精度最大提升了15%。该方法能从OCT原始散点数据中有效提取拟合出更为准确的OCT熔深测量曲线。

关键词：激光技术熔深测量光学相干光层析成像百分位滤波移动平均

Detecting the single chiral molecule during the reaction

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中国科学:材料科学(英文版) 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

煤矿岩巷TBM掘进随掘地震信号特征及其应用

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工矿自动化 2024年第6期50卷 46-53,60页

作者：党保全郭立全张延喜任永乐李圣林淮河能源集团煤业分公司通防地质技术部安徽淮南232000 安徽理工大学地球与环境学院安徽淮南232001 淮河能源集团煤业分公司谢桥煤矿安徽淮南236221 福州华虹智能科技股份有限公司福建福州350003

随掘地震超前探测技术可实现探掘平行,为巷道快速智能掘进场景下实时、精准地质保障提供了可能。随掘震源产生的是复杂、变频、连续信号,信号特征认知直接影响数据处理与成像精度,而目前针对岩巷全断面掘进机(TBM)随掘地震信号特征的认... 详细信息

随掘地震超前探测技术可实现探掘平行,为巷道快速智能掘进场景下实时、精准地质保障提供了可能。随掘震源产生的是复杂、变频、连续信号,信号特征认知直接影响数据处理与成像精度,而目前针对岩巷全断面掘进机(TBM)随掘地震信号特征的认知仍不清晰,且暂时还没有针对性开展过信号处理与成像研究工作。针对上述问题,以谢桥煤矿瓦斯治理巷TBM随掘地震超前探测试验为例,分析了刀盘先导信号与岩壁接收信号的时间域、频率域及时频域特征:岩巷TBM随掘地震信号中不同振幅能量成分比例呈现金字塔形,但分布随机,不对称程度较高;机械运转信号能量较大,刀盘先导信号强度是岩壁接收信号的200倍左右;频率域变频特征明显;机械运转信号基础频率较低,刀盘先导信号频率成分主要集中在10~80 Hz与150~200 Hz,主频为36.99 Hz,岩壁接收信号频率成分主要集中在50~200 Hz,主频为137.97 Hz;刀盘先导信号较岩壁接收信号时频域能量团分布更为规则,多次震源激发现象明显,能量团之间的差异性特征表明了多次震源激发时振幅能量与持续时间的随机性。利用脉冲化算法与绕射叠加偏移成像方法对岩巷TBM随掘地震信号进行数据处理与成像试验,结果表明:(1)脉冲化等效单炮记录与利用常规震源得到的超前探测单炮记录特征一致性较强,同相轴清晰且连续性较好,可满足现场探测分析需要。(2)对探测范围内岩体情况的超前预报结果与实际揭露情况一致,说明岩巷TBM随掘地震超前探测可提供有效地质保障。

关键词：煤矿岩巷掘进随掘地震超前探测随掘地震信号全断面硬岩掘进机刀盘先导信号岩壁接收信号绕射叠加偏移成像

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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