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Guided-yNet: Saliency Feature-Guided Interactive Feature Enhancement Lung tumor Segmentation Network

Computers, Materials and Continua 2024年第3期80卷 4813-4832页

作者： Zhou t. pan y. Lu H. Dang P. Guo y. Wang y. School of Computer Science and Engineering North Minzu University Yinchuan 750021 China Key Laboratory of Image and Graphics Intelligent Processing of State Ethnic Affairs Commission North Minzu University Yinchuan 750021 China School of Medical Information & Engineering Ningxia Medical University Yinchuan 750004 China

Multimodal lung tumor medical images can provide anatomical and functional information for the same lesion. Such as Positron Emission Computed tomography (PEt), Computed tomography (Ct), and PEt-Ct. How to utilize the lesion anatomical and functional information effectively and improve the network segmentation performance are key questions. to solve the problem, the Saliency Feature-Guided Interactive Feature Enhancement Lung tumor Segmentation Network (Guide-yNet) is proposed in this paper. Firstly, a double-encoder single-decoder U-Net is used as the backbone in this model, a single-coder single-decoder U-Net is used to generate the saliency guided feature using PEt image and transmit it into the skip connection of the backbone, and the high sensitivity of PEt images to tumors is used to guide the network to accurately locate lesions. Secondly, a Cross Scale Feature Enhancement Module (CSFEM) is designed to extract multi-scale fusion features after downsampling. thirdly, a Cross-Layer Interactive Feature Enhancement Module (CIFEM) is designed in the encoder to enhance the spatial position information and semantic information. Finally, a Cross-Dimension Cross-Layer Feature Enhancement Module (CCFEM) is proposed in the decoder, which effectively extracts multimodal image features through global attention and multi-dimension local attention. the proposed method is verified on the lung multimodal medical image datasets, and the results show that the Mean Intersection over Union (MIoU), Accuracy (Acc), Dice Similarity Coefficient (Dice), Volumetric overlap error (Voe), Relative volume difference (Rvd) of the proposed method on lung lesion segmentation are 87.27%, 93.08%, 97.77%, 95.92%, 89.28%, and 88.68%, respectively. It is of great significance for computer-aided diagnosis. Copyright © 2024 the Authors. Published by.tech Science Press.

关键词： cross-dimension feature enhancement cross-modal feature enhancement Medical image segmentation saliency feature guidance U-Net

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Editorial for Multiscale&Multifield Coupling in Geomechanics

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1919-1921页

作者： Min Wang Pengzhi pan Andrew H.C.Chan y.t.Feng t-3 Fluid Dynamics and Solid Mechanics Theoretical DivisionLos Alamos National LaboratoryNew MexicoUSA Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhanChina School of Engineering University of TasmaniaTasmaniaAustralia College of Engineering Swansea UniversityWalesUK

We are delighted to serve as guest editors for this special issue in the Journal of Rock Mechanics and Geotechnical *** purpose of this special issue is dedicated to gathering the latest research work on Multiscale&Multifield Coupling in Geomechanics,where we delve into the intricate interplay of various fields and scales that govern the behavior of *** total,30 manuscripts from USA,China,UK,Germany,Canada,India and United Arab Emirates are selected to be included in this issue.

关键词： materials. gathering mechanics

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基于极限分析上限法的地震作用下分层地基盾构隧道开挖面稳定性研究

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岩土力学 2024年第4期45卷 1201-1213页

作者：张治国罗杰朱正国 pan y.t 孙苗苗上海理工大学环境与建筑学院上海200093 石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室河北石家庄050043 新加坡国立大学土木与环境工程系新加坡119077 浙大城市学院土木工程系浙江杭州310015 浙大城市学院城市基础设施智能化浙江省工程研究中心浙江杭州310015

目前针对盾构隧道开挖面稳定性的研究还较少考虑土体分层特性和地震作用的耦合影响,因此构建了一种在分层土体中考虑地震作用的开挖面三维对数螺旋破坏模型进行研究。首先,将地震引起的动态响应通过拟静力法简化为水平和竖直两个方向上... 详细信息

目前针对盾构隧道开挖面稳定性的研究还较少考虑土体分层特性和地震作用的耦合影响,因此构建了一种在分层土体中考虑地震作用的开挖面三维对数螺旋破坏模型进行研究。首先,将地震引起的动态响应通过拟静力法简化为水平和竖直两个方向上的惯性力作用;其次,在均质土体中的三维对数螺旋破坏机制的基础上,将其改进为适用于分层土体的三维对数螺旋破坏机制;再次,根据上限定理,在虚功率方程中引入地震惯性力所做功率,得到考虑土体分层特性和地震作用条件下的盾构隧道开挖面支护力的上限解;最后,将上限理论解与三维数值模拟结果和既有模型试验结果进行对比,得到了较好的一致性。此外,针对水平地震加速度系数和地层厚度对关键物理特征进行了影响因素分析。结果表明,当比例系数ζ>0时,极限支护力随水平地震加速度系数的增大显著增大;当ζ<0时,极限支护力随水平地震加速度系数增大而增大的趋势减弱。当水平地震加速度系数kh=0时,即在无地震作用情况下,归一化极限支护力不随ζ的变化而变化;在上硬下软土层中,下部土层厚度比的增大会引起极限支护力的增大,在上软下硬土层中,下部土层厚度比的增大会引起极限支护力的减小。

关键词：盾构隧道开挖面稳定性地震作用分层土体上限定理

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波流耦合影响下分层海床隧道周围砂土渗流孔压及液化分析

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岩土工程学报 2024年第4期46卷 683-693页

作者：张治国陈金芃朱正国 pan y.t 孙苗苗上海理工大学环境与建筑学院上海200093 石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室河北石家庄050043 国家海洋局北海预报中心山东省海洋生态环境与防灾减灾重点实验室山东青岛266061 新加坡国立大学土木与环境工程系新加坡119077 浙大城市学院土木工程系浙江杭州310015 城市基础设施智能化浙江省工程研究中心浙江杭州310015

目前针对波浪作用下海底盾构隧道周围渗流场的既有理论研究一般将衬砌考虑为不透水介质,较少考虑隧道衬砌的渗透性,尤其是较少考虑波浪与海流共同作用对隧道的影响。此外,既有理论一般将海床视为均质且各向同性工况,忽略了实际情况下分... 详细信息

目前针对波浪作用下海底盾构隧道周围渗流场的既有理论研究一般将衬砌考虑为不透水介质,较少考虑隧道衬砌的渗透性,尤其是较少考虑波浪与海流共同作用对隧道的影响。此外,既有理论一般将海床视为均质且各向同性工况,忽略了实际情况下分层海床的影响。首先,基于波流共同作用下的海床表面的动力边界条件,采用传递-反射矩阵法得到波流共同作用下自由分层海床的孔压响应;其次,采用镜像法建立了由于隧道存在引起的砂土摄动压力控制方程,并利用砂土与衬砌间渗流连续条件获得了该方程的Fourier级数展开解析解;接着,采用叠加原理得到了波流共同作用下分层海床中隧道周围砂土的渗流压力响应及液化判定解答。最后,将理论解析解与数值结果及已有的试验结果进行对比,获得了较好的一致性。此外,针对海床渗透性和隧道衬砌渗透性进行了影响因素分析。结果表明:海流顺流会增大海床中的孔压和液化程度,逆流会减小海床中的孔压并抑制海床的液化,且流速相同时海床对逆流响应的相对差异总体上也大于顺流;当分层海床上层渗透系数较大时(k+s>1×10^(-2)m/s),海床整体孔压较大,且第一次分层处孔压变化明显;当隧道衬砌渗透系数较小时(k+l<1×10^(-6)m/s),隧道对超静孔隙水压在海床内传播“阻挡”效应明显。

关键词：海底盾构隧道分层海床波流耦合渗流孔压传递-反射矩阵法

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Microstructure and Mechanical Property of the Large Cross-Sectioned Mg-Gd-y-Zn-Zr Alloy Produced by Small Extrusion Ratio

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 999-1006页

作者： Sen Wang Hucheng pan Caixia Jiang Zhihao Zeng Zhen pan Weineng tang Chubin yang yuping Ren Gaowu Qin Key Laboratory for Anisotropy and texture of Materials(Ministry of Education) College of Materials Science and EngineeringNortheastern UniversityShenyang110819China Mg and Mg Alloy Institute Technology CenterBaosteel Metal Co.LtdChina Baowu Steel GroupShanghai200940China Jiangxi Provincial Engineering Research Center for Magnesium Alloy Gannan Normal UniversityGanzhou341000China

In this work,the microstructure and mechanical properties of large cross-sectioned Mg-9Gd-3y-1.2Zn-0.5Zr(VWZ931)samples produced by.the small extrusion ratio has been *** as-extruded VWZ931 sample with diameter of~30 mm can exhibit the high yield strength(yS)of 339 MPa,ultimate tensile strength(UtS)of 387 MPa and elongation of 8.2%,*** peak-aged,the yS and UtS of the Mg samples were significantly increased to 435 MPa and 467 *** small extrusion ratio leads to the low fraction of dynamic recry.tallized(DRX)grains in VWZ931 sample,and the texture hardening effect can be fully utilized to achieve high *** combined effect of precipitation strengthening due to the long-period stacking ordered phases and theβ′phase,grain boundary strengthening due to the fine DRX grains,heterogeneous deformation-induced strengthening caused by bimodal microstructure,can together contribute to the high strength of present Mg *** findings can shed light on designing other large-sized Mg wrought alloys with high mechanical performance.

关键词： Mg-RE alloy Mechanical property Bimodal grains texture hardening

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Uphill or downhill?Cropland use change and its drivers from the perspective of slope spectrum

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Journal of Mountain Science 2024年第2期21卷 484-499页

作者： pan Sipei LIANG Jiale CHEN Wanxu PENG yelin College of Land Management Nanjing Agricultural UniversityNanjing 210095China National&Local Joint Engineering Research Center for Rural Land Resources Use and Consolidation Nanjing 210095China Jiangsu Provincial Key Laboratory of Geographic Information technology School of Geography and Ocean ScienceNanjing UniversityNanjing 210023China Key Laboratory of Natural Resources Monitoring and Supervision in Southern Hilly Region Ministry of Natural ResourcesChangsha 410118China yunnan Key Laboratory of Plateau Geographic Processes and Environmental Changes Faculty of GeographyYunnan Normal UniversityKunming 650500China Hubei Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China

the continuous decrease of low-slope cropland resources caused by construction land crowding poses huge threat to regional sustainable development and food *** spectrum analysis of topographic and geomorphic features is considered as a digital terrain analysis method which reflects the macro-topographic features by using micro-topographic ***,pieces of studies have extended the concept of slope spectrum in the field of geoscience to construction land to explore its expansion law,while research on the slope trend of cropland from that perspective remains *** address the gap,in virtue of spatial analysis and geographically weighted regression(GWR)model,the cropland use change in the yangtze River Basin(yRB)from 2000 to 2020 was analyzed and the driving factors were explored from the perspective of slope *** showed that the slope spectrum curves of cropland area-frequency in the yRB showed a first upward then a downward *** change curve of the slope spectrum of cropland in each province(municipality)exhibited various distribution *** analysis of morphological parameters of cropland slope spectrum revealed that the further down the yRB,the stronger the flattening characteristics,the more obvious the *** province experienced the greatest downhill cropland climbing(CLC)was Shannxi,while province experienced the highest uphill CLC was *** most common cropland use change type in the yRB was horizontal expansion *** factors affecting average cropland climbing index(ACCI)were quite stable in different periods,while population density(POP)changed from negative to positive during the study *** research is of practical significance for the rational utilization of cropland at the watershed scale.

关键词： Cropland climbing Land use change Slope spectrum Driving factors Geographically weighted regression yangtze River Basin

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Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： y.X.Wang X.L.Zhu S.M.Weng P.Li X.F.Li H.Ai H.R.pan Z.M.Sheng Key Laboratory for Laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

the generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(tHz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or tHz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or tHz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by.the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and tHz spectral ranges.

关键词： laser ultrashort photon

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Effect of Wave Nonlinearity on the Instantaneous Seabed Liquefaction

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China Ocean Engineering 2024年第1期38卷 93-103页

作者： WANG Zhao-jun SUI ti-ti ZHANG Chi pan Jun-ning Key Laboratory of Port Waterway and Sedimentation Engineering of the Ministry of TransportNanjing Hydraulic Research InstituteNanjing 210024China Key Laboratory of Coastal Disaster and Protection(Hohai University) Ministry of EducationNanjing 210098China the National Key Laboratory of Water Disaster Prevention Nanjing 210098China

the nonlinear variation of wave is commonly seen in nearshore area,and the resulting seabed response and liquefaction are of high concern to coastal *** this study,an analytical formula considering the nonlinear wave skewness and asymmetry is adopted to provide wave pressure on the seabed *** liquefaction depth attenuation coefficient and width growth coefficient are defined to quantitatively characterize the nonlinear effect of wave on seabed *** on the 2D full dynamic model of wave-induced seabed response,a detailed parametric study is carried out in order to evaluate the influence of the nonlinear variation of wave loadings on seabed ***,new empirical prediction formulas are proposed to fast predict the maximum liquefaction under nonlinear *** indicate that(1)Due to the influence of wave nonlinearity.the vertical transmission of negative pore water pressure in the seabed is hindered,and therefore,the amplitude decreases significantly.(2)In general,with the increase of wave nonlinearity.the liquefaction depth of seabed decreases *** under asymmetric and skewed wave loading,the attenuation of maximum seabed liquefaction depth is the most significant among all the nonlinear wave ***,highly skewed wave can cause the liquefaction depth of seabed greater than that under linear wave.(3)the asymmetry of wave pressure leads to the increase of liquefaction width,whereas the influence of skewedness is not significant.(4)Compared with the nonlinear waveform,seabed liquefaction is more sensitive to the variation of nonlinear degree of wave loading.

关键词： nonlinear wave seabed response seabed liquefaction numerical simulation liquefaction prediction

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Fabrication of AZ31/Mg3y Composites with Excellent Strength and Plasticity via Accumulated Rolling Bonding and Diffusion Annealing

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 339-352页

作者： yang Feng Wenhuan Chen Zheng Xu Weijun He Bin Jiang Fusheng pan College of Materials Science and Engineering Chongqing UniversityChongqing400044China International Joint Laboratory for Light Alloys(Ministry of Education) Chongqing UniversityChongqing400044China

AZ31/Mg3y composites with a layer thickness of 100-200μm were fabricated by accumulated rolling bonding(ARB),which was followed by diffusion annealing at 300℃ for 0-32 *** interface layer,containing numerous Al-y precipitates,is formed in the Mg3y layer that is adjacent to the interface as a result of Al diffusing from the AZ31 layers into the Mg3y *** thickness of the interface layer gets increased and more precipitates are formed in the interface layer with the extension of the annealing *** microhardness of the AZ31 and Mg3y layer decreases firstly and then reaches a stable value,while the microhardness of the interface layer increases gradually with the extension of the annealing *** AZ31/Mg3y composites exhibit equivalent strength but increased ductility after diffusion annealing,in comparison to the as-rolled AZ31/Mg3y *** addition,the AZ31/Mg3y composites after annealing always present higher strength and ductility.than AZ31/AZ31 composite,which was fabricated by.the same process as that for the AZ31/Mg3y ***-deformation induced strengthening also plays an important role in the excellent strength and ductility of the annealed AZ31/Mg3y *** study can provide a direction for improving the plasticity and strength of magnesium alloys synergistically.

关键词： AZ31/Mg3y composite Accumulated rolling bonding Diffusion annealing Precipitates Strengthening

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Extraordinary hot extreme in summer 2022 over the yangtze River basin modulated by.the La Nina condition under global warming

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Advances in Climate Change Research 2024年第1期15卷 21-30页

作者： Zhen LIAO yu-Feng yUAN yang CHEN pan-Mao ZHAI State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China

A widespread and prolonged hot extreme hit the yangtze River basin in summer 2022,with 300 sites established new temperature records and nearly 96%stations endured more than 40 hot *** the perspective of the combination effect of the global warming and La Nina condition,potential mechanisms of the hot extreme were *** a record-breaking hot extreme was caused by an extremely strong and westward-shifted western Pacific subtropical high(WPSH).the global warming effect contributed primarily.to the abnormal hot days in the yangtze River basin,coupled with the modulation of the La Nina *** sea surface temperature anomaly pattern under La Nina condition favored more convection activities over the western Pacific,encouraging an enhanced and westward-extended *** addition,an observation-based attribution analysis indicates that anthropogenic warming may increase the probability of such extensively persistent hot extremeby1.8 times.

关键词： Hot extreme the yangtze River basin Global warming tropical Pacific forcing

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