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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 358-378页

作者： Jin-yan zhu yong CHEN School of Mathematical Sciences Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal UniversityShanghai 200062China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

The Gerdjikov-Ivanov(GI)hierarchy is derived via recursion operator,in this article,we mainly investigate the third-order flow GI *** the framework of the Riemann-Hilbert method,the soliton matrices of the third-order flow GI equation with simple zeros and elementary high-order zeros of Riemann-Hilbert problem are constructed through the standard dressing *** advantage of this result,some properties and asymptotic analysis of single soliton solution and two soliton solution are discussed,and the simple elastic interaction of two soliton are *** with soliton solution of the classical second-order flow,we find that the higher-order dispersion term affects the propagation velocity,propagation direction and amplitude of the ***,by means of a certain limit technique,the high-order soliton solution matrix for the third-order flow GI equation is derived.

关键词： Gerdjikov-Ivanov hierarchy third-order flow GI equation Riemann-Hilbert method high-order soliton

Partial Collapsing Degeneration of Floer Trajectories and Adiabatic Gluing

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Acta Mathematica Sinica,English Series 2024年第1期40卷 161-249页

作者： yong-Geun OH Ke zhu Center for Geometry and Physics Institute for Basic Science(IBS)79 Jigok-ro 127beon-gilNam-guPohang-siGyeongsangbuk-doKorea 37673&POSTECHGyeongsangbuk doKorea Department of Mathematics and Statistics Minnesota State UniversityMankatoMN 56001USA

In the present paper,we study partial collapsing degeneration of Hamiltonian-perturbed Floer trajectories for an adiabatic ε-family and its reversal adiabatic gluing,as the prototype of the partial collapsing degeneration of 2-dimensional(perturbed)J-holomorphic maps to 1-dimensional gradient *** consider the case when the Floer equations are S^(1)-invariant on parts of their domains whose adiabatic limit has positive length as ε→0,which we call thimble-flow-thimble *** main gluing theorem we prove also applies to the case with Lagrangian boundaries such as in the problem of recovering holomorphic disks out of pearly *** particular,our gluing theorem gives rise to a new direct proof of the chain isomorphism property between the Morse-Bott version of Lagrangian intersection Floer complex of L by Fukaya-Oh-Ohta-Ono and the pearly complex of L Lalonde and *** also provides another proof of the present authors’earlier proof of the isomorphism property of the PSS map without involving the target rescaling and the scale-dependent gluing.

关键词： Floer trajectory equation partial collapsing degeneration thimble-flow-thimble moduli space adiabatic gluing exponential decay estimates three-interval method

FPGA-based position reconstruction method for neutron beam flux spatial distribution measurement in BNCT

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Nuclear Science and Techniques 2024年第3期35卷 96-108页

作者： Wei Jiang ping Cao Yi-Ming Wu Xian-Ke Liu zhu-Jun Fang Zhi-yong Zhang Bin Shi Jun Chen State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China National Key Laboratory for Metrology and Calibration Techniques China Institute of Atomic EnergyBeijing 102413China

A new measurement method for the spatial distribution of neutron beam flux in boron neutron capture therapy(BNCT)is being developed based on the two-dimensional Micromegas *** address the issue of long processing times in traditional offline position reconstruction methods,this paper proposes a field programmable gate array based online position reconstruction method utilizing the micro-time projection chamber *** method encapsulates key technical aspects:a self-adaptive serial link technique built upon the dynamical adjustment of the delay chain length,fast sorting,a coordinate-matching technique based on the mapping between signal timestamps and random access memory(RAM)addresses,and a precise start point-merging technique utilizing a circular combined *** performance test of the selfadaptive serial link shows that the bit error rate of the link is better than 10-12 at a confidence level of 99%,ensuring reliable data *** experiment utilizing the readout electronics and Micromegas detector shows a spatial resolution of approximately 1.4 mm,surpassing the current method’s resolution level of 5 *** beam experiment confirms that the readout electronics system can obtain the flux spatial distribution of neutron beams online,thus validating the feasibility of the position reconstruction *** online position reconstruction method avoids traditional methods,such as bubble sorting and traversal searching,simplifies the design of the logic firmware,and reduces the time complexity from O(n2)to O(n).This study contributes to the advancement in measuring neutron beam flux for BNCT.

关键词： Position reconstruction FPGA Readout electronics Neutron flux spatial distribution

UAV-assisted cooperative offloading energy efficiency system for mobile edge computing

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Digital Communications and Networks 2024年第1期10卷 16-24页

作者： Xue-yong Yu Wen-Jin Niu Ye zhu Hong-Bo zhu Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing210003China Engineering Research Centerof Health Service System Based on Ubiquitous Wireless Networks Ministry of EducationNanjng Universityof Posts and Telecommunications Nanjing210003China

Reliable communication and intensive computing power cannot be provided effectively by temporary hot spots in disaster areas and complex terrain ground *** this has greatly developed the application and integration of UAV and Mobile Edge Computing(MEC)to the Internet of Things(loT).However,problems such as multi-user and huge data flow in large areas,which contradict the reality that a single UAV is constrained by limited computing power,still *** to allowing UAV collaboration to accomplish complex tasks,cooperative task offloading between multiple UAVs must meet the interdependence of tasks and realize parallel processing,which reduces the computing power consumption and endurance pressure of *** the computing requirements of the user terminal,delay constraint of a computing task,energy constraint,and safe distance of UAV,we constructed a UAV-Assisted cooperative offloading energy efficiency system for mobile edge computing to minimize user terminal energy ***,the resulting optimization problem is originally nonconvex and thus,difficult to solve *** tackle this problem,we developed an energy efficiency optimization algorithm using Block Coordinate Descent(BCD)that decomposes the problem into three convex ***,we jointly optimized the number of local computing tasks,number of computing offloaded tasks,trajectories of UAV,and offloading matching relationship between multi-UAVs and multiuser *** results show that the proposed approach is suitable for different channel conditions and significantly saves the user terminal energy consumption compared with other benchmark schemes.

关键词： Computation offloading Internet of things(IoT) Mobile edge computing(MEC) Block coordinate descent(BCD)

Broadband high-efficiency plasmonic metalens with negative dispersion characteristic

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Photonics Research 2024年第4期12卷 813-820页

作者： yong-QIANG LIU yong zhu HONGCHENG YIN JINHAI SUN YAN WANG yongXING CHE National Key Laboratory of Scattering and Radiation Beijing 100854China

Controlling the dispersion characteristic of metasurfaces(or metalenses) along a broad bandwidth is of great importance to develop high-performance broadband metadevices. Different from traditional lenses that rely on the material refractive index along the light trajectory, metasurfaces or metalenses provide a new regime of dispersion control via a sub-wavelength metastructure, which is known as negative chromatic ***, broadband metalenses design with high-performance focusing especially with a reduced device dimension is a significant challenge in society. Here, we design, fabricate, and demonstrate a broadband highperformance diffractive-type plasmonic metalens based on a circular split-ring resonator metasurface with a relative working bandwidth of 28.6%. The metalens thickness is only 0.09λ0(λ0is at the central wavelength),which is much thinner than previous broadband all-dielectric metalenses. The full-wave simulation results show that both high transmissive efficiency above 80%(the maximum is even above 90%) and high average focusing efficiency above 45%(the maximum is 56%) are achieved within the entire working bandwidth of 9–12 ***, an average high numerical aperture of 0.7(NA = 0.7) of high-efficiency microwave metalens is obtained in the simulations. The broadband high-performance metalens is also fabricated and experimental measurements verify its much higher average focusing efficiency of 55%(the maximum is above 65% within the broad bandwidth) and a moderate high NA of 0.6. The proposed plasmonic metalens can facilitate the development of wavelength-dependent broadband diffractive devices and is also meaningful to further studies on arbitrary dispersion control in diffractive optics based on plasmonic metasurfaces.

关键词： resonator dispersion high

Chain Extender-induced Hydrogen Bonding Organization Determines the Morphology and Properties of Thermoplastic Polycarbonate Polyurethane

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Chinese Journal of Polymer Science 2024年第1期42卷 87-96,I0009页

作者： Yi-Lang Qin ping zhu Chen-Xi Ouyang Xia Dong Fuwai Hospital Chinese Academyof Medical Sciences&Peking Union Medical College/National Center for Cardiovascular DiseasesBejing 100037China CASKey Laboratoryof Engineering Plastics CAS Research/Education Centerfor Excellence in Molecular SciencesInstitute ofChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Thermoplastic polycarbonate polyurethanes(PCUs) are multiblock copolymers that have been applied for medical devices for long time. Aliphatic diols are common chain extenders(CE) involved in the composition of the hard segments of PCU. However, limited knowledge was discovered about how the chemical structure of CE affects the hydrogen bonding organization within PCUs and their mechanical *** investigate this problem, a group of PCUs were synthesized respectively by extending the polymer chain with 1,4-butanediol(BDO),aminoethanol(MEA), ethanediol(EO) as three kinds of chain extenders. Tiny differences in the CE chemical structure results in remarkable variations in phase separation, condensed morphologies, thermal and mechanical properties, which are characterized by Fourier transform infrared spectrometer, atomic force microscopy, small-angle X-ray scattering, differential scanning calorimetry, and tensile tests. The microstructural evolution during unilateral deformation and the different mechanism induced by the different CEs was probed and unveil by in situ wide-and small-angle X-ray diffraction. Symmetry of CE can improve the organization of the hydrogen bonding. The coherence strength of the urethane/urea group also plays a key role by comparing the two PCUs with ethanediol and aminoethanol.

关键词： Thermoplastic polycarbonate polyurethane Chain extender Hydrogen bonding Mechanical properties

3D robust anisotropic diffusion filtering algorithm for sparse view neutron computed tomography 3D image reconstruction

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Nuclear Science and Techniques 2024年第3期35卷 13-29页

作者： Yang Liu Teng-Fei zhu Zhi Luo Xiao-ping Ouyang School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China State Key Laboratory of Intense Pulsed Radiation Simulation and Effect Xi’an 710024China

The most critical part of a neutron computed tomography(NCT) system is the image processing algorithm,which directly affects the quality and speed of the reconstructed *** types of noise in the system can degrade the quality of the reconstructed ***,to improve the quality of the reconstructed images of NCT systems,efficient image processing algorithms must be *** anisotropic diffusion filtering(ADF) algorithm can not only effectively suppress the noise in the projection data,but also preserve the image edge structure information by reducing the diffusion at the image ***,we propose the application of the ADF algorithm for NCT image *** compare the performance of different algorithms in NCT systems,we reconstructed images using the ordered subset simultaneous algebraic reconstruction technique(OS-SART) algorithm with different regular terms as image processing *** the iterative reconstruction,we selected two image processing algorithms,the Total Variation and split Bregman solved total variation algorithms,for comparison with the performance of the ADF ***,the filtered back-projection algorithm was used for comparison with an iterative *** reconstructing the projection data of the numerical and clock models,we compared and analyzed the effects of each algorithm applied in the NCT *** on the reconstruction results,OS-SART-ADF outperformed the other algorithms in terms of denoising,preserving the edge structure,and suppressing *** example,when the 3D Shepp–Logan was reconstructed at 25 views,the root mean square error of OS-SART-ADF was the smallest among the four iterative algorithms,at only *** universal quality index,mean structural similarity,and correlation coefficient of the reconstructed image were the largest among all algorithms,with values of 0.9877,0.9878,and 0.9887,respectively.

关键词： NCT OS-SART Sparse-view Anisotropic diffusion filtering

Percutaneous transhepatic cholangioscopy-assisted biliary polypectomy for local palliative treatment of intraductal papillary neoplasm of the bile duct

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1821-1832页

作者： Xu Ren yong-ping Qu Chun-Lan zhu Xiao-Hong Xu Hong Jiang Yi-Xia Lu Hong-Peng Xue Digestive Disease Hospital of Heilongjiang Provincial Hospital Heilongjiang Provincial Clinical Medical Research Center for Minimally Invasive Diagnosis and Treatment of Pancreaticobiliary DiseasesHarbin 150001Heilongjiang ProvinceChina Digestive Endoscopy Center of Heilongjiang Provincial Hospital Heilongjiang Provincial Clinical Medical Research Center for Minimally Invasive Diagnosis and Treatment of Pancreaticobiliary DiseasesHarbin 150001Heilongjiang ProvinceChina Second Department of Gastroenterology Digestive Disease Hospital of Heilongjiang Provincial Hospitaland Heilongjiang Provincial Clinical Medical Research Center for Minimally Invasive Diagnosis and Treatment of Pancreaticobiliary DiseasesHarbin 150001Heilongjiang ProvinceChina Department of Pathology Heilongjiang Provincial HospitalHarbin 150001Heilongjiang ProvinceChina

BACKGROUND Intraductal papillary neoplasm of the bile duct(IPNB)is a premalignant biliarytype epithelial neoplasm with intraductal papillary or villous *** reported local palliative therapeutic modalities,including endoscopic nasobiliary drainage,stenting and biliary curettage,endoscopic biliary polypectomy,percutaneous biliary drainage,laser ablation,argon plasma coagulation,photodynamic therapy,and radiofrequency ablation to relieve mechanical obstruction are limited with weaknesses and *** have applied percutaneous transhepatic cholangioscopy(PTCS)-assisted biliary polypectomy(PTCS-BP)technique for the management of IPNB including mucin-hypersecreting cast-like and polypoid type tumors since *** To assess the technical feasibility,efficacy,and safety of PTCS-BP for local palliative treatment of *** Patients with mucin-hypersecreting cast-like or polypoid type IPNB and receiving PTCS-BP between September 2010 and December 2019 were ***-BP was performed by using a half-moon type snare with a soft stainless-steel wire,and the tumor was snared and resected with *** primary outcome was its feasibility,indicated by technical *** secondary outcomes were efficacy,including therapeutic success,curative resection,and clinical success,and *** Five patients(four with mucin-hypersecreting cast-like type and one with polypoid type IPNB)were ***-and high-grade intraepithelial neoplasia(HGIN)and recurrent IPNB with invasive carcinoma were observed in one,two,and two patients,*** cholangitis and/or obstructive jaundice were presented in all four patients with mucin-hypersecreting cast-like type *** five patients achieved technical success of *** patients(three with mucin-hypersecreting cast-like type and one with polypoid type IPNB)obtained therapeutic success;one with mucin-hypersecreting cast-like type tumors in the intrahepatic small bile duct and HGIN h

关键词： Intraductal papillary neoplasm of the bile duct Percutaneous transhepatic cholangioscopy Biliary polypectomy Feasibility Efficacy

Topological non-reciprocal robust waveguide transport

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 39-45页

作者： Ruizhi Dong Yihuan zhu Dongxing Mao Xu Wang yong Li Institute of Acoustics Tongji UniversityShanghai 200092China

Devices that surpass the restriction of reciprocity of classical physical waves have brought intriguing possibilities for wave ***-reciprocal acoustic devices that rely on the viscosity of the medium or nonlinear effect have low efficiency and distortion problems respectively,and poor immunity to *** appearance of acoustic topological insulators achieves nonreciprocal transport with high ***,the local nature of topological states means that their appearance depends on a system with a larger *** is,most of the area of a topological device is occupied by useless lattices that do not directly contribute to non-reciprocal *** extra cost of topology protection severely limits the application scenarios of topology states,decreases the cost-effectiveness of topology devices,and is not conducive to device miniaturization and *** this work,we construct an acoustic three-layer heterojunction by introducing two types of domain walls into a conventional quantum Hall effect acoustic topological insulator,and successfully construct a non-reciprocal scattering network that forms topological modes spanning the interlayer *** extended states are still protected by bulk-band topology,making their non-reciprocity robust against *** structure flawlessly realizes the path broadening in a two-dimensional topological system and can accomplish functions such as non-reciprocal acoustic splitting and multichannel *** work opens up opportunities for developing topological-insulator-based non-reciprocal devices in acoustics.

关键词： reciprocal topological topology

Advancements in S-scheme heterojunction materials for photocatalytic environmental remediation

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Journal of Materials Science & Technology 2024年第2期169卷 182-198页

作者： Changliang Nie Xiaohan Wang ping Lu Yukun zhu Xin Li Hua Tang School of Environmental Science and Engineering State Key Laboratory of Bio-fibers and Eco-textilesQingdao UniversityQingdao266071China Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou510642China School of Environmental Science and Engineering Shandong UniversityQingdao266237China

Recently,S-scheme heterojunctions have gained considerable attention in the field of photocatalytic environmental remediation as their potential to achieve efficient spatial charge separation coupled with strong redox ***,this review provides an overview of the current state-of-the-art in the development of S-scheme-based photocatalysts for the purification of environmental *** review first covers the fundamentals of heterogeneous photocatalysis for environmental ***,an introduction to the background,mechanism,design principles,and characterization techniques of S-scheme heterojunctions is ***,the review presents a comparison and summary of using various S-scheme photocatalysts for the removal of several target pollutants,such as bacteria,heavy metals,nitrogen oxides,antibiotics,and ***,the modification strategies of S-scheme heterojunction photocatalysts are also ***,a brief discussion of the challenges and prospects associated with S-scheme photocatalytic systems is demonstrated.

关键词： S-scheme heterojunctions Photocatalyst Pollutant Environmental remediation