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International Journal of Disaster Risk Science 2024年第2期15卷 277-289页

作者： Shuai zhou Crystal Kwan Department of Applied Social Sciences The Hong Kong Polytechnic UniversityHong Kong 999077China

Despite the well-documented impacts of single natural hazards like earthquakes, less is known about the psychological adaptation to multiple natural hazards, particularly in rural areas. This study investigated the associations of multiple natural hazards with depression among Chinese adults. Data were retrieved from the China Family Panel Studies conducted during 2010–2018. With a sample of 11,633 Chinese adults, multilevel logistic regression was employed to examine the relationships between natural hazard exposure and depression in the total sample and different age groups. Overall, experiencing four or more natural hazards was associated with a higher risk of being depressed. Regarding hazard type, the number of hydrometeorological and biological hazards was associated with a higher likelihood of depression, whereas the number of geologic and other hazards was related to a lower risk of depression. Middle-aged adults from villages were more likely to be affected by natural hazard exposure than older and younger adults. The findings of this study show that cumulative exposure to natural hazards can generate lasting effects on depressive symptoms, particularly in middle adulthood. The findings also suggest that older adults from rural areas may have accumulated more resilience to mitigate the adverse well-being effects of hazard events. Policies and interventions should enhance disaster awareness and preparation for aging residents from multi-hazard communities.

关键词： Age differences China Depressive symptoms Multi-hazard communities Natural hazard exposure

MCIF-Transformer Mask RCNN:Multi-Branch Cross-Scale Interactive Feature Fusion Transformer Model for PET/CT Lung Tumor Instance Segmentation

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Computers, Materials & Continua 2024年第6期79卷 4371-4393页

作者： Huiling Lu Tao zhou School of Medical Information&Engineering Ningxia Medical UniversityYinchuan750004China School of Computer Science and Engineering North Minzu UniversityYinchuan750021China Key Laboratory of Image and Graphics Intelligent Processing of State Ethnic Affairs Commission NorthMinzu UniversityYinchuan750021China

The precise detection and segmentation of tumor lesions are very important for lung cancer computer-aided ***,in PET/CT(Positron Emission Tomography/Computed Tomography)lung images,the lesion shapes are complex,the edges are blurred,and the sample numbers are *** solve these problems,this paper proposes a Multi-branch Cross-scale Interactive Feature fusion Transformer model(MCIF-Transformer Mask RCNN)for PET/CT lung tumor instance segmentation,The main innovative works of this paper are as follows:Firstly,the ResNet-Transformer backbone network is used to extract global feature and local feature in lung *** pixel dependence relationship is established in local and non-local fields to improve the model perception ***,the Cross-scale Interactive Feature Enhancement auxiliary network is designed to provide the shallow features to the deep features,and the cross-scale interactive feature enhancement module(CIFEM)is used to enhance the attention ability of the fine-grained ***,the Cross-scale Interactive Feature fusion FPN network(CIF-FPN)is constructed to realize bidirectional interactive fusion between deep features and shallow features,and the low-level features are enhanced in deep semantic ***,4 ablation experiments,3 comparison experiments of detection,3 comparison experiments of segmentation and 6 comparison experiments with two-stage and single-stage instance segmentation networks are done on PET/CT lung medical image *** results showed that APdet,APseg,ARdet and ARseg indexes are improved by 5.5%,5.15%,3.11%and 6.79%compared with Mask RCNN(resnet50).Based on the above research,the precise detection and segmentation of the lesion region are realized in this *** method has positive significance for the detection of lung tumors.

关键词： PET/CT images instance segmentation mask RCNN interactive fusion transformer

Numerical design of an efficient Ho^(3+)-doped InF3 fiber laser at~3.2μm

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Journal of Electronic Science and Technology 2024年第3期22卷 35-46页

作者： Shi-Yuan zhou Hong-Yu Luo Ya-zhou Wang Yong Liu State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu611731China DTU Electro Technical University of DenmarkKongens Lyngby2800Denmark

In this work,we theoretically unlock the potential of Ho^(3+)-doped InF3 fiber for efficient~3.2μm laser generation(from the 5F4,5S2→5F5 transition),by employing a novel dual-wavelength pumping scheme at 1150 nm and 980 nm,for the first *** clad-coupled 1150 nm pumping of 5 W,~3.2μm power of 3.6 W has been predicted with the optical-to-optical efficiency of 14.4%.Further efficient power scaling,however,is blocked by the output saturation with 980 nm *** alleviate this behavior,the cascaded 5I5→5I6 transition,targeting~3.9μm,has been activated simultaneously,therefore accelerating the population circulation between the laser upper level 5F4,5S2 and long-lived 5I6 level under 980 nm *** a result,enhanced~3.2μm power of 4.68 W has been obtained with optical-to-optical efficiency of 15.6%.Meanwhile the~3.9μm laser,yielding power of 2.76 W with optical-to-optical efficiency of 9.2%,is theoretically achievable as well with a moderate heat load,of which the performance is even better than the prior experimentally and theoretically reported Ho^(3+)-doped InF3 fiber lasers emitting at~3.9μm *** work demonstrates a versatile platform for laser generation at~3.2μm and~3.9μm,thus providing the new opportunities for many potential applications,e.g.,polymer processing,infrared countermeasures,and free-space communications.

关键词： Cascaded Fiber laser Holmium Mid-infrared

Weighted multilinear p-adic Hardy operators and commutators on p-adic Herz-type spaces

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 554-570页

作者： MA Teng zhou Jiang College of Mathematics and System Sciences Xinjiang UniversityUrumqi 830046China

In this paper,we introduce the weighted multilinear p-adic Hardy operator and weighted multilinear p-adic Ces`aro operator,we also obtain the boundedness of these two operators on the product of p-adic Herz spaces and p-adic Morrey-Herz spaces,the corresponding operator norms are also established in each ***,the boundedness of commutators of these two operators with symbols in central bounded mean oscillation spaces and Lipschitz spaces on p-adic Morrey-Herz spaces are also given.

关键词： Morrey-Herz spaces weighted multilinear p-adic Hardy operator commutators operator norms

Resource Allocation for Channel Estimation in Reconfigurable Intelligent Surface-Aided Multi-Cell Networks

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Journal of Communications and Information Networks 2024年第1期9卷 64-79页

作者： Yining Xu Sheng zhou Department of Electronic Engineering Beijing National Research Center for Information Science and TechnologyTsinghua UniversityBeijing 100084China

Reconfigurable intelligent surface(RIS)is a promising solution to deal with the blockage-sensitivity of millimeter wave band and reduce the high energy consumption caused by network densification. However, deploying large scale RISs may not bring expected performance gain due to significant channel estimation overhead and non-negligible reflected *** this paper,we derive the analytical expressions of the coverage probability, area spectrum efficiency(ASE)and energy efficiency (EE)of a downlink RIS-aided multi-cell *** order to optimize the network performance, we investigate the conditions for the optimal number of training symbols of each antenna-to-antenna and antenna-to-element path (referred to as the optimal unit training overhead) in channel *** study shows that:1)RIS deployment is not“the more, the better”, only when blockage objects are dense should one deploy more RISs;2) the coverage probability is maximized when the unit training overhead is designed as large as possible;3)however,the ASE-and-EE-optimal unit training overhead exists. It is a monotonically increasing function of the frame length and a monotonically decreasing function of the average signal-to-noise-ratio (in the high signal-to-noise-ratio region). Additionally,the optimal unit training overhead is smaller when communication nodes deploy particularly few or many antennas.

关键词： reconfigurable intelligent surface multi-cell network directional transmissions channel estimation resource allocation stochastic geometry

Approaching the commercial threshold of solar water splitting toward hydrogen byⅢ-nitrides nanowires

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Frontiers in Energy 2024年第1期18卷 122-124页

作者： Baowen zhou Shuhui SUN Key Laboratory for Power Machinery and Engineering of the Ministry of Education School of Mechanical EngineeringShanghai Jiao Tong UniveristyShanghai 200240China Institut National de la Recherche Scientifique(INRS)-CenterÉnergie Matériaux Télécommunications VarennesQuebec J3X 1P7Canada

In a recent article in Nature,Mi and coworkers from the University of Michigan reported a solar-to-hydrogen(STH)efficiency of>9%in converting water into hydrogen and oxygen[1],which represents an important breakthrough in this field due to the benchmarking leap in STH efficiency of photocatalytic overall water splitting under natural sunlight.

关键词： breakthrough splitting Michigan

Bayesian inference of neutron-skin thickness and neutron-star observables based on effective nuclear interactions

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 97-105页

作者： Jia zhou Jun Xu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Physics Science and Engineering Tongji UniversityShanghai 200092China

We have obtained the constraints on the density dependence of the symmetry energy from neutron-skin thickness data by parityviolating electron scatterings and neutron-star observables using a Bayesian approach,based on the standard Skyrme-HartreeFock(SHF)model and its extension as well as the relativistic mean-field(RMF)*** the neutron-skin thickness data(neutron-star observables)mostly constrain the symmetry energy at subsaturation(suprasaturation)densities,they may more or less constrain the behavior of the symmetry energy at suprasaturation(subsaturation)densities,depending on the energy-density functional *** showing the final posterior density dependence of the symmetry energy,we also compare the slope parameters of the symmetry energy at 0.10 fm-3as well as the values of the symmetry energy at twice saturation density from three effective nuclear *** present work serves as a comparison study based on relativistic and non-relativistic energy-density functionals,for constraining the nuclear symmetry energy from low to high densities using a Bayesian approach.

关键词： symmetry energy neutron skin neutron star

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An Improved Bounded Conflict-Based Search for Multi-AGV Pathfinding in Automated Container Terminals

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2705-2727页

作者： Xinci zhou Jin Zhu Shanghai Maritime University Logistics Science and Engineering Research InstituteShanghai200000China

As the number of automated guided vehicles(AGVs)within automated container terminals(ACT)continues to rise,conflicts have becomemore *** point and edge conflicts ofAGVs,amulti-AGVconflict-free path planning model has been formulated to minimize the total path length of AGVs between shore bridges and *** larger terminalmaps and complex environments,the grid method is employed to model AGVs’road *** improved bounded conflict-based search(IBCBS)algorithmtailored to ACT is proposed,leveraging the binary tree principle to resolve conflicts and employing focal search to expand the search *** experiments involving 60 AGVs indicate a reduction in computing time by 37.397%to 64.06%while maintaining the over cost within 1.019%.Numerical experiments validate the proposed algorithm’s efficacy in enhancing efficiency and ensuring solution quality.

关键词： Automated terminals multi-AGV multi-agent path finding(MAPF) conflict based search(CBS) AGV path planning

考虑矿井水流速和时效影响的煤矿地下水库储水系数计算模型

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采矿与安全工程学报 2024年第4期41卷 778-789页

作者：汪北方周铎蒋嘉祺梁冰辽宁工程技术大学矿业学院辽宁阜新123000 煤炭开采水资源保护与利用全国重点实验室北京100011 山东科技大学山东省矿山灾害预防控制重点实验室山东青岛266590 辽宁工程技术大学力学与工程学院辽宁阜新123000

选取神东矿区拟建地下水库22614工作面为研究背景,利用工作面开采相似实验和矿井水浸砂岩加载实验,模拟采场覆岩运动规律和应力分布状态,分析采空区覆岩结构特征,建立考虑矿井水流速和时间效应影响的煤矿地下水库储水系数计算模型。研... 详细信息

选取神东矿区拟建地下水库22614工作面为研究背景,利用工作面开采相似实验和矿井水浸砂岩加载实验,模拟采场覆岩运动规律和应力分布状态,分析采空区覆岩结构特征,建立考虑矿井水流速和时间效应影响的煤矿地下水库储水系数计算模型。研究结果表明:模型工作面开采基本顶初次垮落步距46 cm,基本顶周期垮落步距7~16 cm;采空区覆岩仅存在裂隙带和垮落带,垮落带岩块间存在大量非完全接触的空洞、空隙及欠压实裂缝,是煤矿地下水库最主要的储水空间;采空区岩体承载应力沿走向基本呈“∩”形分布,最大应力趋于1.5 MPa,覆岩位移以走向中心线为对称轴呈“∪”形变化,最大位移为-2.5 cm。基于采空区覆岩关键层运移轨迹构建其底面下沉曲线函数方程,数学量化采空区垮落带体积、垮落带岩体空隙量和吸水量,建立包含岩石碎胀系数等参数构成的煤矿地下水库储水系数计算模型,通过明确砂岩碎胀系数与矿井水流速和时间的数学关系,进一步完善煤矿地下水库储水系数计算模型,并对模型进行实例计算和实验验证,模型计算储水系数0.1965,实验测定储水系数0.2104,证明了计算模型的准确性,可为煤矿地下分布式水库库容设计和储水调度提供重要理论依据。

关键词：关键层岩石碎胀系数矿井水流速度时间效应储水系数

单向碳/碳复合材料拉-拉疲劳寿命及剩余强度预测模型

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复合材料学报 2018年第8期35卷 2293-2301页

作者：朱元林温卫东刘礼华周佳琪黄盛彬江苏法尔胜研发中心有限公司江阴214433 国家金属线材制品工程技术研究中心江阴214433 南京航空航天大学能源与动力学院南京210016

基于预测单向复合材料纵向拉伸强度的随机核模型,引入纤维单丝剩余强度二参数Weibull模型及纤维单丝与基体界面剩余强度模型,研究建立了单向复合材料纵向拉-拉疲劳寿命及剩余强度的预测模型。对经过一定次数拉-拉疲劳载荷循环后的纤维... 详细信息

基于预测单向复合材料纵向拉伸强度的随机核模型,引入纤维单丝剩余强度二参数Weibull模型及纤维单丝与基体界面剩余强度模型,研究建立了单向复合材料纵向拉-拉疲劳寿命及剩余强度的预测模型。对经过一定次数拉-拉疲劳载荷循环后的纤维束抽取其纤维单丝进行剩余强度拉伸试验,建立了纤维单丝剩余强度的二参数Weibull模型,测试单向碳/碳(C/C)复合材料的纤维与基体界面强度。通过单向C/C复合材料算例分析表明,92.5%、90.6%和87.5%应力水平下对数预测寿命与对数试验寿命比值分别为0.79、1.00和1.11,表明所建立的寿命预测模型用于预测单向C/C复合材料疲劳寿命是可行的;纵向拉伸剩余强度预测值与试验值误差在10%以内,吻合较好,表明所提出的剩余强度预测模型具有较高的精度。

关键词：单向复合材料随机核模型疲劳寿命剩余强度预测模型