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Spatial distributions of soil nutrients affected by land use,topography and their interactions,in the Loess Plateau of china

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International Soil and Water conservation Research 2024年第1期12卷 227-239页

作者： Wenxin Zhou changjia li Wenwu Zhao lindsay c.Stringer Bojie Fu State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina Institute of Land Surface System and Sustainable Development Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina Department of environment and Geography University of YorkYorkUK York environmental Sustainability Institute University of YorkYorkUK

Soil nutrient availability and their spatial distributions are strongly related to land use and landscape *** study aims to address the knowledge gap regarding the interaction between these factors and the underlying *** selected five land uses(grassland with Artemisia gmelinii,woodland with Robinia pseudoacacia,shrubland with caragana korshinskii and Hippophae rhamnoides,and apple orchard with Malus pumila)and nine slope positions across hillslopes in the Loess Plateau,china,to investigate their combined effects on the contents and stocks of soil organic carbon(SOc),total nitrogen(TN)and total phosphorus(TP).Parametric and non-parametric statistical tests were conducted to determine the significant differences in the means or the medians of the soil nutrient *** showed that the SOc and TN contents of shrubland with caragana korshinskii were statistically significantly greater than those of the grassland(pc and TN contents generally decreased from the upper slope to the middle slope,and to the foot slope for the grassland,woodland and shrublands,and on the contrary,an increasing trend from the upper slope,to the middle slope,and to the foot slope was identified for the apple *** study highlights that land use,slope position and their interaction have significant effects on the spatial distributions of soil *** provides essential empirical evidence for the identification of the optimal vegetation type and slope positions in land management and vegetation restoration activities.

关键词： Soil organic carbon Total nitrogen Total phosphorus Slope position Vegetation restoration

Re-Distributing Facial Features for engagement Prediction with ModernTcN

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computers, Materials and continua 2024年第1期81卷 369-391页

作者： li X. Zhu W. li Q. Hou c. Zhang Y. college of Information and Artificial Intelligence Nanchang Institute of Science and Technology Nanchang 330108 China School of Electrical and Information engineering Wuhan Institute of Technology Wuhan 430205 China School of Electronic Information engineering Wuhan Donghu University Wuhan 430212 China

Automatically detecting learners’ engagement levels helps to develop more effective online teaching and assessment programs, allowing teachers to provide timely feedback and make personalized adjustments based on students’ needs to enhance teaching effectiveness. Traditional approaches mainly rely on single-frame multimodal facial spatial information, neglecting temporal emotional and behavioural features, with accuracy affected by significant pose variations. Additionally, convolutional padding can erode feature maps, affecting feature extraction’s representational capacity. To address these issues, we propose a hybrid neural network architecture, the redistributing facial features and temporal convolutional network (RefEIP). This network consists of three key components: first, utilizing the spatial attention mechanism large kernel attention (LKA) to automatically capture local patches and mitigate the effects of pose variations; second, employing the feature organization and weight distribution (FOWD) module to redistribute feature weights and eliminate the impact of white features and enhancing representation in facial feature maps. Finally, we analyse the temporal changes in video frames through the modern temporal convolutional network (ModernTcN) module to detect engagement levels. We constructed a near-infrared engagement video dataset (NEVD) to better validate the effic.ency of the RefEIP network. Through extensive experiments and in-depth studies, we evaluated these methods on the NEVD and the Database for Affect in Situations of Elicitation (DAiSEE), achieving an accuracy of 90.8% on NEVD and 61.2% on DAiSEE in the four-class classification task, indicating significant advantages in addressing engagement video analysis problems. © 2024 The Authors. Published by Tech Sc.ence Press.

关键词： engagement prediction re-distributing facial features spatiotemporal network temporal convolutional network

Progress on the antiferromagnetic topological insulator MnBi2Te4

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National Sc.ence Review 2024年第2期11卷 33-49页

作者： Shuai li Tianyu liu chang liu Yayu Wang Hai-Zhou Lu X.c.Xie Department of Physics Harbin Institute of Technology Shenzhen Institute for Quantum Sc.ence and engineering and Department of Physics Southern University of Science and Technology(SUSTech) Quantum Sc.ence center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong) Shenzhen Key Laboratory of Quantum Sc.ence and engineering International Quantum Academy Beijing Academy of Quantum Information Sc.ences Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of Physics Renmin University of China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua University Frontier Sc.ence center for Quantum Information Hefei National Laboratory International center for Quantum Materials School of Physics Peking University Institute for Nanoelectronic Devices and Quantum computing Fudan University

Topological materials, which feature robust surface and/or edge states, have now been a research focus in condensed maTher physics. They represent a new class of materials exhibiting nontrivial topological phases,and provide a platform for exploring exotic transport phenomena, such as the quantum anomalous Hall effect and the quantum spin Hall effect. Recently, magnetic topological materials have attracted considerable interests due to the possibility to study the interplay between topological and magnetic *** particular, the quantum anomalous Hall and axion insulator phases can be realized in topological insulators with magnetic order. MnBi2Te4, as the first intrinsic antiferromagnetic topological insulator discovered, allows the examination of existing theoretical predictions; it has been extensively studied, and many new discoveries have been made. Here we review the progress made on MnBi2Te4from both experimental and theoretical aspects. The bulk crystal and magnetic structures are surveyed first, followed by a review of theoretical calculations and experimental probes on the band structure and surface states, and a discussion of various exotic phases that can be realized in MnBi2Te4. The properties of MnBi2Te4thin films and the corresponding transport studies are then reviewed, with an emphasis on the edge state transport. Possible future research directions in this field are also discussed.

关键词： MnBi2Te4 magnetic topological insulator antiferromagnetic quantum anomalous Hall effect axion insulator

Doped low-density parity-check codes

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Digital communications and Networks 2024年第1期10卷 217-226页

作者： Yong li Rui liu Xianlong Jiao Youqiang Hu Zhen Luo Francis c.M.Lau college of computer Sc.ence Chongqing UniversityChongqing400044China School of Automation Chongqing UniversityChongqing400044China college of Electronic and Information engineering Southwest UniversityChongqing400715China Future Wireless Networks and IoT Focusing Area Department of Electronic and Information EngineeringHong Kong Polytechnic UniversityHong KongChina

In this paper,we propose a doping approach to lower the error floor of Low-Density Parity-check(LDPc)*** doping component is a short block code in which the information bits are selected from the coded bits of the dominant trapping sets of the LDPc ***,an algorithm for selecting the information bits of the short code is proposed,and a specific two-stage decoding algorithm is *** results demonstrate that the proposed doped LDPc code achieves up to 2.0 dB gain compared with the original LDPc code at a frame error rate of 10^(-6)Furthermore,the proposed design can lower the error floor of original LDPc codes.

关键词： LDPc codes Doped LDPc codes Tanner graph Quadratic residue codes Trapping sets

Two-photon polymerization lithography for imaging optics

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International Journal of Extreme Manufacturing 2024年第4期6卷 21-60页

作者： Hao Wang c.eng-Feng Pan chi li Kishan S Menghrajani Markus A Schmidt Aoling li Fu Fan Yu Zhou Wang Zhang Hongtao Wang Parvathi Nair Suseela Nair John You en chan Tomohiro Mori Yueqiang Hu Guangwei Hu Stefan A Maier Haoran Ren Huigao Duan Joel K W Yang college of Mechanical and Vehicle engineering Hunan UniversityChangsha 410082People's Republic of China engineering Product Development Singapore University of Technology and DesignSingapore 487372Singapore Greater Bay Area Institute for Innovation Hunan UniversityGuangzhou 511300People's Republic of China Department of Electrical and computer engineering National University of Singapore4 Engineering Drive 3Singapore 117576Singapore School of Physics and Astronomy Faculty of ScienceMonash UniversityMelbourneVictoria 3800Australia Leibniz Institute of Photonic Technology 07745 JenaGermany Abbe center of Photonics and Faculty of Physics FSU Jena07745 JenaGermany Otto Schott Institute of Material Research FSU Jena07745 JenaGermany Institute of Materials Research and engineering A*STAR(Agency for Science Technology and Research)Singapore 138634Singapore Industrial Technology center of Wakayama Prefecture Wakayama 6496261Japan School of Electrical and Electronic.engineering Nanyang Technological UniversitySingapore639798Singapore Department of Physics Imperial College LondonLondon SW72AZUnited Kingdom

Optical imaging systems have greatly extended human visual capabilities,enabling the observation and understanding of diverse *** technologies span a broad spectrum of wavelengths from x-ray to radio frequencies and impact research activities and our daily *** glass lenses are fabricated through a series of complex processes,while polymers offer versatility and ease of ***,modern applications often require complex lens assemblies,driving the need for miniaturization and advanced designs with micro-and nanoscale features to surpass the capabilities of traditional fabrication ***-dimensional(3D)printing,or additive manufacturing,presents a solution to these challenges with benefits of rapid prototyping,customized geometries,and effic.ent production,particularly suited for miniaturized optical imaging *** 3D printing methods have demonstrated advantages over traditional counterparts,yet challenges remain in achieving nanoscale ***-photon polymerization lithography(TPL),a nanoscale 3D printing technique,enables the fabrication of intricate structures beyond the optical diffraction limit via the nonlinear process of two-photon absorption within liquid *** offers unprecedented abilities,***-free fabrication,micro-and nanoscale capabilities,and rapid prototyping of almost arbitrary complex 3D *** this review,we emphasize the importance of the criteria for optical performance evaluation of imaging devices,discuss material properties relevant to TPL,fabrication techniques,and highlight the application of TPL in optical *** the first panoramic review on this topic,it will equip researchers with foundational knowledge and recent advancements of TPL for imaging optics,promoting a deeper understanding of the *** leveraging on its high-resolution capability,extensive material range,and true 3D processing,alongside advances in materials,fabrication,and design,we en

关键词： two-photon polymerization lithography 3D printing additive manufacturing imaging optics and nanophotonics

Injury Mortality of children and Adolescents Aged 0–19 Years—china,2010–2021

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china cDc weekly 2024年第14期6卷 294-299,I0001-I0006页

作者： Jingtao Zhou Min Zhao Hao Huang David c.Schwebel Peishan Ning Zhenzhen Rao Peixia c.eng li li Guoqing Hu Department of Epidemiology and Health Statistics Hunan Provincial Key Laboratory of Clinical EpidemiologyXiangya School of Public HealthCentral South UniversityChangsha CityHunan ProvinceChina Department of Psychology University of Alabama at BirminghamBirminghamALUSA Department of child Adolescent and Women’s HealthSchool of Public HealthCapital Medical UniversityBeijingChina National clinical Research center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha CityHunan ProvinceChina

Introduction:To examine the recent trends in child injury mortality in ***:Injury mortality data of 2010–2021 for children and adolescents aged 0–19 years were from the china Health Statistics *** mortality disparities across urban *** locations,gender,and age groups were *** percent change(APc),average annual percent change(AAPc),and their 95%confidence intervals(95%cI)were estiamted usimg Joinpoint regression ***:The age-standardized injury mortality significantly dropped from 21.87 to 9.41 per 100,000 population among children and youth aged 0–19 years during 2010–2021,with an AAPc of−6.7%(95%cI:−8.2%,−5.2%).The urban-rural disparity and gender gap in injury mortality reduced *** 2021,drowning and road traffic crashes were the top two causes of child injury deaths,explaing 31.1%and 27.9%of total injury deaths,*** accounted for 62.3%of injury deaths among infants younger than a ***,the suicide mortality rate rose from 2.16 to 3.42 per 100,000 population between 2010 and 2021 among teenagers aged 15–19 *** analyses yielded similar ***:During 2010–2021,the injury mortality decreased significantly among chinese children and adolescents,and the responding urbanrural disparities narrowed.

关键词： injury younger narrow

Effect of trigger system on experimental dispersion characteristics of active surface wave testing

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Earthquake engineering and engineering Vibration 2024年第2期23卷 311-318页

作者： lin Shibin Jeramy c.Ashlock Zhu liming Qin Zexiang li Bo Zhu Xingji Zhai changhai State Key Laboratory of Precision Blasting Jianghan UniversityWuhan 430056China Hubei Key Laboratory of Blasting engineering Jianghan UniversityWuhan 430056China Department of civil Construction&Environmental EngineeringIowa State UniversityAmesIA 50010USA Wuhan Airport Road Development co. Ltd.Wuhan 430065China School of civil and environmental engineering Harbin Institute of TechnologyShenzhen 518055China Key Lab of Structures Dynamic Behavior and control of the Ministry of Education Harbin Institute of TechnologyHarbin 150090China Key Lab of Smart Prevention and Mitigation of civil engineering Disaster of the Ministry of Industry and Information Technology Harbin Institute of TechnologyHarbin 150090China

A trigger system is typically employed in active seismic testing to trigger and synchronize multichannel surface wave data *** effect of the trigger system on the dispersion image of surface waves is empirically known to be negligible,however,theoretical explanation regarding the effect of the trigger system is *** study systematically examines the theory for surface wave dispersion analysis and proves that the effect of the trigger system on a dispersion image is negligible via a solid theoretical ***,based on the new theoretical explanation,an alternative method that uses only the relative phase difference between sensors to extract dispersion characteristics with better conceptual clarity is *** active surface wave testing cases are considered to validate the theory and *** results indicate that(1)an accurate trigger system is not necessary for surface wave data acquisition,and(2)it is unnecessary to assume that the impact point is the generation point of the surface waves for the experimental dispersion analysis.

关键词： site investigation surface waves data acquisition dispersion

Theoretical and experimental study of a bi-stable piezoelectric.energy harvester under hybrid galloping and band-limited random excitations

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Applied Mathematics and Mechanics(english Edition) 2024年第3期45卷 461-478页

作者： Haitao li Tianyu ZHenG Weiyang QIN Ruilan TIAN Hu DING J.c.JI liqun c.en Department of engineering Mechanics North University of ChinaTaiyuan 030051China Department of engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China Department of engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Shanghai Key Laboratory of Mechanics in energy engineering Shanghai Frontier Science Center of MechnoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Mechanical and Mechatronic.engineering University of Technology SydneyNew South Wales 2007Australia

In the practical environment,it is very common for the simultaneous occurrence of base excitation and *** the combined energy of vibration and wind with a single energy harvesting structure is *** this purpose,the effects of the wind speed and random excitation level are investigated with the stochastic averaging method(SAM)based on the energy *** results of the analytical prediction are verified with the Monte-carlo method(McM).The numerical simulation shows that the introduction of wind can reduce the critical excitation level for triggering an inter-well jump and make a bi-stable energy harvester(BEH)realize the performance enhancement for a weak base ***,as the strength of the wind increases to a particular level,the influence of the random base excitation on the dynamic responses is weakened,and the system exhibits a periodic galloping response.A comparison between a BEH and a linear energy harvester(LEH)indicates that the BEH demonstrates inferior performance for high-speed *** experiments are conducted to investigate the validity of the theoretical prediction and numerical *** experimental findings also show that strong random excitation is favorable for the BEH in the range of low wind ***,as the speed of the incoming wind is up to a particular level,the disadvantage of the BEH becomes clear and evident.

关键词： bi-stability inter-well response galloping band-limited random

Broadband bidirectional Brillouin–Raman random fiber laser with ultra-narrow linewidth

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chinese Physics B 2024年第2期33卷 371-376页

作者：杨茜李阳邹辉梅杰徐恩明张祖兴 Advanced Photonic Technology Laboratory College of Electronic and Optical Engineering&College of MicroelectronicsNanjing University of Posts and TelecommunicationsNanjing 210023China

We present a Brillouin–Raman random fiber laser(BRRFL)with full-open linear cavity structure to generate broadband Brillouin frequency comb(BFc)with double Brillouin-frequency-shift *** incorporation of a regeneration portion consisting of an erbium-doped fiber and a single-mode fiber enables the generation of broadband *** dynamics of broadband BFc generation changing with the pump power(EDF and Raman)and Brillouin pump(BP)wavelength are investigated in detail,*** suitable conditions,the bidirectional BRRFL proposed can produce a flatamplitude BFc with 40.7-nm bandwidth ranging from 1531 nm to 1571.7 nm,and built-in 242-order Brillouin Stokes lines(BSLs)with double Brillouin-frequency-shift ***,the linewidth of single BSL is experimentally measured to be about 2.5 *** broadband bidirectional narrow-linewidth BRRFL has great potential applications in optical communication,optical sensing,spectral measurement,and so on.

关键词： random laser fiber laser stimulated Brillouin scattering(SBS) stimulated Raman scattering(SRS)