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Journal of Electronic Science and Technology 2024年第3期22卷 69-79页

作者： Yin Zhang ding-feng Duan School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu611731China

We estimate tree heights using polarimetric interferometric synthetic aperture radar(PolInSAR)data constructed by the dual-polarization(dual-pol)SAR data and random volume over the ground(RVoG)*** the Sentinel-1 SAR dual-pol(SVV,vertically transmitted and vertically received and SVH,vertically transmitted and horizontally received)configuration,one notes that S_(HH),the horizontally transmitted and horizontally received scattering element,is *** S_(HH)data were constructed using the SVH data,and polarimetric SAR(PolSAR)data were *** proposed approach was first verified in simulation with satisfactory *** was next applied to construct PolInSAR data by a pair of dual-pol Sentinel-1A data at Duke Forest,North Carolina,*** to local observations and forest descriptions,the range of estimated tree heights was overall *** the heights with the ICESat-2 tree heights at 23 sampling locations,relative errors of 5 points were within±30%.Errors of 8 points ranged from 30%to 40%,but errors of the remaining 10 points were>40%.The results should be encouraged as error reduction is *** instance,the construction of PolSAR data should not be limited to using SVH,and a combination of SVH and SVV should be ***,an ensemble of tree heights derived from multiple PolInSAR data can be considered since tree heights do not vary much with time frame in months or one season.

关键词： Constructed polarimetric SAR data Dual polarization Sentinel-1 SAR data Polarimetric interferometric SAR Random volume over the ground model Tree height estimation

Effect of hot isostatic pressure on the microstructure and tensile properties of γ'-strengthened superalloy fabricated through induction-assisted directed energy deposition

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1089-1097页

作者： Jianjun Xu Hanlin ding Xin Lin feng Liu Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

The microstructure characteristics and strengthening mechanism of Inconel738LC(IN-738LC) alloy prepared by using induction-assisted directed energy deposition(IDED) were elucidated through the investigation of samples subjected to IDED under 1050℃ preheating with and without hot isostatic pressing(HIP,1190℃,105 MPa,and 3 h).Results show that the as-deposited sample mainly consisted of epitaxial columnar crystals and inhomogeneously distributed γ’ phases in interdendritic and dendritic core *** HIP,grain morphology changed negligibly,whereas the size of the γ’ phase became increasingly *** further heat treatment(HT,1070℃,2 h + 845℃,24 h),the γ’ phase in the as-deposited and HIPed samples presented a bimodal size distribution,whereas that in the as-deposited sample showed a size that remained *** comparison of tensile properties revealed that the tensile strength and uniform elongation of the HIP + HTed sample increased by 5% and 46%,respectively,due to the synergistic deformation of bimodal γ’phases,especially large cubic γ’ ***,the relationship between phase transformations and plastic deformations in the IDEDed sample was discussed on the basis of generalized stability theory in terms of the trade-off between thermodynamics and kinetics.

关键词： directed energy deposition Ni-based superalloys high-temperature preheating hot isostatic pressing microstructure tensile properties

Sound event localization and detection based on deep learning

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Journal of Systems Engineering and Electronics 2024年第2期35卷 294-301页

作者： ZHAO Dada ding Kai QI Xiaogang CHEN Yu feng Hailin School of Mathematics and Statistics Xidian UniversityXi’an 710071China Science and Technology on Near-Surface Detection Laboratory Wuxi 214035China

Acoustic source localization(ASL)and sound event detection(SED)are two widely pursued independent research *** recent years,in order to achieve a more complete spatial and temporal representation of sound field,sound event localization and detection(SELD)has become a very active research *** paper presents a deep learning-based multioverlapping sound event localization and detection algorithm in three-dimensional ***-Mel spectrum and generalized cross-correlation spectrum are joined together in channel dimension as input *** features are classified and regressed in parallel after training by a neural network to obtain sound recognition and localization results *** channel attention mechanism is also introduced in the network to selectively enhance the features containing essential information and suppress the useless ***,a thourough comparison confirms the efficiency and effectiveness of the proposed SELD *** experiments show that the proposed algorithm is robust to reverberation and environment and can achieve higher recognition and localization accuracy compared with the baseline method.

关键词： sound event localization and detection(SELD) deep learning convolutional recursive neural network(CRNN) channel attention mechanism

Effects of surface energy and substrate on modulus determination of biological films by conical indentation

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Science China(Technological Sciences) 2024年第6期67卷 1757-1764页

作者： ding Yue LI Cheng-Ya NIU XinRui WANG Gang-feng Department of Engineering Mechanics SVLXi’an Jiaotong UniversityXi’an710049China Department of Mechanical Engineering City University of Hong KongHong Kong SAR999077China

Micro-/nano-indentation has become prevalent in evaluating the mechanical characteristics of biological samples,such as cells and ***,the existing contact models describing conical indentation ignore the joint effects of surface energy and substrate,and consequently cannot accurately extract the Young's modulus of biological samples deposited on *** finite element methods,we examine the conical indentation of biological films on substrates while taking surface energy into *** on the dimensional analysis,the explicit relationship between load and indentation depth is achieved for films with their moduli varying from 0.001 to 100 times that of the *** the classical Sneddon's model was employed to analyze the load-depth data,the measured modulus could reach 18 times the real modulus for films on harder substrates,but only 4%of the real modulus for films on softer ***,in micro-/nano-indentations,neglecting the contribution of surface energy would result in an overestimation of the Young's modulus of films depending on the contact *** analytical expression provided here can be utilized to precisely deduce the mechanical characteristics of biological films deposited on substrate from the load and indentation depth data of a conical indentation.

关键词： biological film surface effect substrate effect indentation

Strong Limit Theorems for Weighted Sums under the Sub-linear Expectations

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 862-874页

作者： feng-xiang feng ding-cheng WANG Qun-ying WU Hai-wu HUANG School of Mathematics and Statistics Guilin University of TechnologyGuilin 541004China School of Mathematical Science University of Electronic Science and Technology of ChinaChengdu 611731China School of Science Guilin University of Aerospace TechnologyGuilin 541004China

In this article,we study strong limit theorems for weighted sums of extended negatively dependent random variables under the sub-linear *** establish general strong law and complete convergence theorems for weighted sums of extended negatively dependent random variables under the sub-linear *** results of strong limit theorems are more general than some related results previously obtained by Thrum(1987),Li et al.(1995)and Wu(2010)in classical probability space.

关键词： sub-linear expectation complete convergence complete moment convergence the maximal weighted sums

Tailoring chaotic motion of microcavity photons in ray and wave dynamics by tuning the curvature of space

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 107-112页

作者： Wei Lin Yechun ding Yongsheng Wang Peng Li Yanpeng Zhang feng Yun feng Li Key Laboratory for Physical Electronics and Devices of the Ministry of Education Shaanxi Key Lab of Information Photonic TechniqueSchool of Electronic Science and EngineeringFaculty of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an 710049China Department of Electrical and Photonics Engineering Technical University of DenmarkKgs.Lyngby 2800Denmark Center for Regenerative and Reconstructive Medicine Med-X InstituteThe First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061China Solid-State Lighting Engineering Research Center Xi’an Jiaotong UniversityXi’an 710049China

Microcavity photon dynamics in curved space is an emerging interesting area at the crossing point of nanophotonics,chaotic science,and non-Euclidean *** report the sharp difference between the regular and chaotic motions of cavity photons subjected to the varying space *** the island modes of regular motion rise in the phase diagram in the curved space,the chaotic modes show special mechanisms to adapt to the space curvature,including the fast diffusion of ray dynamics,and the localization and hybridization of the Husimi wavepackets among different periodic *** observations are unique effects enabled by the combination of the chaotic trajectory,the wave nature of light,and the non-Euclidean orbital motion,and therefore make the system a versatile optical simulator for chaotic science under quantum mechanics in curved space-time.

关键词： microcavity chaotic motion curved space

Modifying effects and mechanisms of superfine stainless wires on microstructures and mechanical properties of ultra-high performance seawater sea-sand concrete

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Science China Technological Sciences 2024年第10期67卷 3205-3220页

作者： YU feng DONG SuFen ASHOUR Ashraf ding SiQi HAN BaoGuo School of Infrastructure Engineering Dalian University of Technology Faculty of Engineering & Informatics University of Bradford Department of Civil and Environmental Engineering The Hong Kong Polytechnic University

Ultra-high-performance seawater sea-sand concrete（UHPSSC） presents a prospective solution to address the natural resource shortage in marine infrastructure construction. To eliminate the corrosion risk of steel fibers and broaden the applicability of UHPSSC, this study investigates the mechanical properties and free chloride ion content as well as microstructures of UHPSSC reinforced with superfine stainless wires（SSWs） under natural curing. The results indicate that 1.5% SSWs can remarkably improve the flexural strength and toughness of UHPSSC by 127% and 1724%, respectively, and mitigate the long-term strength degradation of UHPSSC. The strong interfacial bond between SSW and UHPSSC improves the compactness of UHPSSC, thus reducing the growth space for Ca（OH）2crystals and swelling hydration products generated by sulfate and magnesium ions. This can be supported by the observed reduction in the Ca/Si ratio of C–S–H gels, CH crystal orientation index, and ***, through mechanisms such as pull-out, rupture, overlapping network, and internal anchor interface, SSWs effectively prevent microcrack growth and propagation, transforming single long-connected microcracks into multiple-emission microcracks centered on SSW. Additionally, the free chloride ion content of the composites at 28 and 180 d meets the ACI 318-19 standard requirements for concrete exposed to seawater. This compliance is attributed to the chloride immobilization facilitated by Friedel's salt and C–S–H gels within the interfaces around SSWs and sea-sand. Consequently, SSWs-reinforced UHPSSC exhibits considerable potential for applications in sustainable marine infrastructures, demanding long-term mechanical properties and high durability.

关键词： ultra-high performance seawater sea-sand concrete superfine stainless wire mechanical properties chloride ion content microstructure

Deformation characteristics of ultra-deep circular shaft in soft soil:A case study

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Underground Space 2024年第3期16卷 239-260页

作者： Yafei Qiao feng Xie Zhanwei Bai Jiafeng Lu Wenqi ding Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China Engineering Project Management Company Shanghai Chengtou Water GroupShanghai 200002China SGIDI Engineering Consulting(Group)Co. Ltd.Shanghai 200093China

A circular shaft is often used to access a working well for deep underground space *** the depth of underground space increases,the excavation depth of the shaft *** this study,the deformation characteristics of a circular shaft with a depth of 56.3 m were presented and *** main monitoring contents included:(1)wall deflection;(2)vertical wall movement;(3)horizontal soil movement;(4)vertical surface movement;and(5)basal ***,the maximum wall deflection was only 7.7 *** with the wall deflection data collected for another 29 circular excavations,the ratio of maximum wall deflection to excavation depth of this shaft was smaller due to a smaller ratio of diameter to excavation *** wall deflection underwent two stages of deformation:the first stage was mainly circumferential compression caused by the mutual extrusion of joints between walls,and the second stage was typical vertical deflection *** horizontal soil movement outside the shaft was greater than the wall deflection and the deep soil caused great horizontal movement because of dewatering at confined water ***,a basal heave of 203.8 mm occurred in the pit centre near the ***,the shaft was uplifted over time and showed 3 stages of vertical *** surface outside the shaft exhibited settlement and uplift deformation at different locations due to different *** basal heave caused by excavation was the dominant factor,driving the vertical movement of the shaft as well as the surrounding *** correlation between the wall deflection and the surface settlement outside the shaft was weak.

关键词： Circular shaft Site monitoring Deflection Vertical deformation Soft soil

MYB2 and MYB108 regulate lateral root development by interacting with LBD29 in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2024年第8期66卷 1675-1687页

作者： feng Zhang Junxia Wang Tingting ding Xuefeng Lin Haiying Hu Zhaojun ding Huiyu Tian The Key Laboratory of Plant Development and Environmental Adaptation Biology Ministry of EducationSchool of Life SciencesShandong UniversityQingdao 266237China Advanced Medical Research Institute Cheeloo College of MedicineShandong UniversityJinan 250012China

AUXIN RESPONSE FACTOR 7(ARF7)-mediated auxin signaling plays a key role in lateral root(LR)development by regulating downstream LATERAL ORGAN BOUNDARIES DOMAIN(LBD)transcription factor genes,including LBD16,LBD18,and *** proteins are believed to regulate the transcription of downstream genes as homodimers or ***,whether LBD29 forms dimers with other proteins to regulate LR development remains ***,we determined that the Arabidopsis thaliana(L.)*** transcription factors MYB2 and MYB108 interact with LBD29 and regulate auxin-induced LR *** MYB2 and MYB108 were induced by auxin in an ARF7-dependent *** of MYB2 by fusion with an SRDX domain severely affected auxin-induced LR formation and the ability of LBD29 to induce LR *** contrast,overexpression of MYB2 or MYB108 resulted in greater LR numbers,except in the lbd29 mutant *** findings underscore the interdependence and importance of MYB2,MYB108,and LBD29 in regulating LR *** addition,MYB2–LBD29 and MYB108–LBD29 complexes promoted the expression of CUTICLE DESTRUCTING FACTOR 1(CDEF1),a member of the GDSL(Gly-Asp-Ser-Leu)lipase/esterase family involved in LR *** summary,this study identified MYB2–LBD29 and MYB108–LBD29 regulatory modules that act downstream of ARF7 and intricately control auxin-mediated LR development.

关键词： ARF7 auxin lateral roots LBD29 MYB108 MYB2

SS-LASS Zircon Dating Deciphering Multiple Episodes of Anatexis in a Deeply-Subducted Continental Crust:An Example from Sulu Orogen,China

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Journal of Earth Science 2024年第1期35卷 85-98页

作者： Peng feng Lu Wang Xiawen Li Wenjie ding Zhe Chen School of Resource&Environment and Safety Engineering University of South ChinaHengyang 421001China State Key Laboratory of Geological Processes and Mineral Resources Center for Global TectonicsSchool of Earth SciencesChina University of GeosciencesWuhan 430074China No.8 Institute of Geology and Mineral Resources Exploration of Shandong Province Rizhao 276826China

‘Single shot'laser-ablation split-stream(SS-LASS)technique analyzing unpolished zircon grains makes their thin rims tenable for determination,which thus offers great potential in deciphering the timing of multiple and short-lived episodes of anatexis and metamorphism in deeplysubducted continental *** granitic gneisses in the deeply subducted continental crust undergoing considerable fluid-melt activities persist multistage growth of ***,a comparative study of SS-LASS and laser ablation inductively coupled plasma mass spectrometer(LA-ICP-MS)zircon dating was conducted on the granitic gneisses from the Sulu belt in this *** mostly show a core-mantle-rim structure with CL-bright rims thinner than 5μ*** LA-ICP-MS dating,relict magmatic zircon cores yield protolith ages of ca.756-747 Ma;whereas the dark mantles record synexhumation anatexis at ca.214 *** contrast,according to the U-Pb dates,trace element features,zircon crystallization temperatures and geological context,SS-LASS zircon petrochronology deciphers three episodes of anatectic events,as follows:(i)the first episode of anatexis at ca.218-217 Ma dominated by phengite-breakdown melting,likely facilitating the exhumation of the UHP slice from mantle depth;(ii)the second episode of anatexis at ca.193–191 Ma indicating part of northern Dabie-Sulu belt was still“hot”because of buried in the thickened orogenic crust at that time;(iii)the third episode of anatexis(ca.162–161 Ma)consistent with the intrusion ages(ca.161–141 Ma)of the Jurassic to Cretaceous granitoids in this orogen,suggesting the initial collapse of the orogenic root of the Sulu belt occurred at Late Jurassic due to the Izanagi plate initially subducting beneath the margin of Eastern *** study sheds new light upon the utilization of SS-LASS petrochronology deciphering multiple anatectic events in the deeply-subducted continental crust and supports us in better understanding the tectonic evolution of Dabie-

关键词： anatexis laser ablation laser-ablation split-stream ultrahigh-pressure metamorphic belt Sulu Orogen