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Performance of composite foundations with different load transfer platforms and substratum stiffness over silty clay

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Journal of Mountain Science 2024年第5期21卷 1761-1774页

作者： zhang shuming LIU Yan YUAN Shengyang LIU Xianfeng JIANG Guanlu LIU Junyan School of Civil Engineering and Architecture University of JinanJinan 250022China The Engineering Technology Research Center for Urban Underground Engineering Supporting and Risk Monitoring of Shandong Province Jinan 250022China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of High-speed Railway Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China

The semi-rigid pile-supported composite foundation is widely used in highway projects due to its effectiveness in increasing the bearing capacity and stability of foundations.It is crucial to understand the stress distribution across the embankment width and the behaviour of unreinforced foundations.Thus,five centrifuge tests were conducted to examine the bearing and deformation behaviours of NPRS(Non-Connected Piled Raft Systems)and GRPS(GeosyntheticReinforced Pile-Supported systems)with varying substratum stiffness,then a comparative analysis was conducted on embankment settlement,pressures underneath the embankments,and axial forces along the piles.The results indicated that greater substratum stiffness correlates with reduced settlement and deformation at various depths.Deformation occurring 5 meters from the embankment toe includes settlement in NPRS and upward movement in GRPS.The potential sliding surface is primarily located within the embankment in NPRS,whereas it may extend through both the embankment and foundation in GRPS.The pile-soil stress ratio and efficiency in NPRS are higher than in GRPS across the embankment.The axial force borne by end-bearing piles is significantly greater than that by floating piles.As the buried depth increases,the axial force in GRPS initially rises then declines,whereas in NPRS,it remains relatively constant within a certain range before decreasing.This study aids in assessing the applicability of composite foundations in complex railway environments and provides a reference for procedural measures under similar conditions.

关键词： Centrifuge modelling Composite foundation Failure mode Load transfer platform Substratum Stiffness Silty clay

Ni/Pd-based ohmic contacts to p-GaN through p-InGaN/p^(+)-GaN contacting layers

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Journal of Semiconductors 2022年第9期43卷 81-86页

作者： Minglong zhang Masao Ikeda Siyi Huang Jianping Liu Jianjun Zhu shuming zhang Hui Yang School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026China Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of SciencesSuzhou 215123China

Specific contact resistance to p-GaN was measured for various structures of Ni/Pd-based metals and thin(20-30 nm thick)p-InGaN/p^(+)-GaN contacting layers.The effects of surface chemical treatment and annealing temperature were ex-amined.The optimal annealing temperature was determined to be 550°C,above which the sheet resistance of the samples de-graded considerably,suggesting that undesirable alloying had occurred.Pd-containing metal showed~35%lower com-pared to that of single Ni.Very thin(2-3.5 nm thick)p-InGaN contacting layers grown on 20-25 nm thick p^(+)-GaN layers exhib-ited one to two orders of magnitude smaller values of compared to that of p^(+)-GaN without p-InGaN.The current density de-pendence of,which is indicative of nonlinearity in current-voltage relation,was also examined.The lowest achieved through this study was 4.9×10^(-5)Ω·cm^(2)@J=3.4 kA/cm^(2).

关键词： GaN ohmic contact specific contact resistance

基于BP神经网络模型优化Fe_(1-x)O基氨合成催化剂

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化工进展 2024年第3期43卷 1302-1308页

作者：张书铭刘化章浙江工业大学工业催化研究所浙江杭州310014

运用BP神经网络建立了助催化剂含量与催化剂活性之间的预测模型,对Fe_(1-x)O基氨合成催化剂的助催化剂进行优化。首先将前期实验数据整理归纳为含有3、4、5、6和7个助催化剂等5类催化剂,以助催化剂含量(体积分数)为输入变量,以425℃反... 详细信息

运用BP神经网络建立了助催化剂含量与催化剂活性之间的预测模型,对Fe_(1-x)O基氨合成催化剂的助催化剂进行优化。首先将前期实验数据整理归纳为含有3、4、5、6和7个助催化剂等5类催化剂,以助催化剂含量(体积分数)为输入变量,以425℃反应器出口氨浓度(活性)为输出变量,对助催化剂进行优化。结果表明,BP神经网络预测模型拟合值均方误差最高为0.2784,预测值均方误差最高为0.1592,构建的BP神经网络模型准确度较高。在该模型的基础上,运用多种群遗传算法进行极值寻优,求解最优的催化剂配方,并进行实验验证。结果表明,根据优化结果制备5个样品的实验测定值与预测值的相对误差最高为2.88%,优化结果较为准确;含有7个助催化剂的催化剂活性最高为18.83%,比原样本的统计平均活性值(17.52%)高1.31%,相对提高7.48%,助催化剂含量优化取得满意的结果。

关键词： Fe_(1-x)O 催化剂助催化剂神经网络遗传算法优化

MultiTrans:Multi-scale feature fusion transformer with transfer learning strategy for multiple organs segmentation of head and neck CT images

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Medicine in Novel Technology and Devices 2023年第2期18卷 181-190页

作者： Yufang He Fan Song Wangjiang Wu Suqing Tian Tianyi zhang shuming zhang Peng zhang Chenbin Ma Youdan Feng Ruijie Yang Guanglei zhang Beijing Advanced Innovation Center for Biomedical Engineering School of Biological Science and Medical EngineeringBeihang UniversityBeijing100191China Department of Radiation Oncology Cancer CenterPeking University Third HospitalBeijing100191China

Radiotherapy with precise segmentation of head and neck organs at risk(OARs)is one of the important treatment methods for head and neck cancer.In routine clinical practice,OARs are manually segmented by doctors to avoid irreversible adverse reactions caused by radiotherapy,which is time-consuming and laborious.To assist doctors in OARs segmentation,a MultiTrans framework with a multi-scale feature fusion module was proposed in this paper.In the multi-scale feature fusion module,the original image and the feature map of CNN were fused together to form a compound feature map for more complete high-resolution global information.In addition,the global information was also fully utilized in MultiTrans by using the feature map restored from the compound feature map in the skip connection.The multi-scale interactive high-resolution information can make full use of medical image information and obtain features more comprehensively,thus improve the segmentation accuracy.Experiments showed that MultiTrans had an average Dice score coefficient(DSC)of 74.01%in all organs,effectively improved segmentation accuracy.In addition,we proposed a transfer learning strategy for small organs by transferring the weight parameters of organs with a large amount of data to organs with a small amount of data to speed up the convergence of MultiTrans and reduce the demand for data volume in the MultiTrans.With this strategy,the average DSC of small organs was obviously increased,making the segmentation of small organs more accurate.The proposed framework and transfer learning strategy have the potential of assisting doctors in OARs delineation.

关键词： Head and neck cancer Deep learning CT images Organ segmentation

Effect of microstructure of Au80Sn20 solder on the thermal resistance TO56 packaged GaN-based laser diodes

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Journal of Semiconductors 2020年第10期41卷 29-32页

作者： Hao Lin Deyao Li Liqun zhang Pengyan Wen shuming zhang Jianping Liu Hui Yang School of Materials Science and Engineering Shanghai UniversityShanghai 201900China Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of SciencesSuzhou 215123China

Au80Sn20 alloy is a widely used solder for laser diode packaging.In this paper,the thermal resistance of Ga N-based blue laser diodes packaged in TO56 cans were measured by the forward voltage method.The microstructures of Au80Sn20 solder were then investigated to understand the reason for the difference in thermal resistance.It was found that the microstructure with a higher content of Au-rich phase in the center of the solder and a lower content of(Au,Ni)Sn phase at the interface of the solder/heat sink resulted in lower thermal resistance.This is attributed to the lower thermal resistance of Au-rich phase and higher thermal resistance of(Au,Ni)Sn phase.

关键词： Au80Sn20 laser diodes package thermal resistance

A new type of anionic surfactant with four carboxylates for the preparation of mesoporous materials

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Frontiers of Materials Science 2012年第3期6卷 268-277页

作者： Lin-Hao SUN Song WANG Wei-Lin SHI shuming zhang Xi CHEN Qiang CAI Department of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Department of Materials Science and Engineering WhitingSchoolof EngineeringJohns Hopkins University3400 N.Charles St.BaltimoreMD 21218USA

In this paper, a new type of anionic surfactant containing four carboxylates was synthesized by a four-step synthetic reaction including bromination reaction and primary amide protective reaction. Intermediates and final products of each step in the whole synthetic process were characterized by IH NMR and MS. Purification of the anionic surfactant was accomplished through combination of recrystallization and silica gel column chromatography. The structure and the critical micelle concentration （CMC） of this surfactant at different temperatures were also investigated. Unlike traditional mono- carboxylate surfactant easy to form lamellar mesostructure, this surfactant has the hexagonal mesophase structure and comparatively low CMC, hopefu.lly to be applied in the preparation of mesoporous metal oxides.

关键词： surfactant four carboxylates hexagonal mesosphase critical micelleconcentration （CMC）

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基于高效通道注意力的多阶段图像去雨网络

电光与控制 2024年第4期31卷 109-114,120页

作者：李国金张书铭林森陶志勇辽宁工程技术大学电子与信息工程学院辽宁葫芦岛125000 沈阳理工大学自动化与电气工程学院沈阳110000

针对现有图像去雨算法不能更好地保留图像背景细节的问题,提出一种基于高效通道注意力的多阶段图像去雨网络。首先,网络使用3×3卷积提取雨图的浅层特征并传递给高效通道注意力模块,为不同的特征通道分配不同的权重;然后,传递给3个并行... 详细信息

针对现有图像去雨算法不能更好地保留图像背景细节的问题,提出一种基于高效通道注意力的多阶段图像去雨网络。首先,网络使用3×3卷积提取雨图的浅层特征并传递给高效通道注意力模块,为不同的特征通道分配不同的权重;然后,传递给3个并行阶段,在前2个阶段中,使用编码-解码器进行多尺度特征提取,减少雨纹信息丢失,其中使用Transformer模块抑制无用信息传递;最后,在第3个阶段使用初始分辨率模块代替编码-解码器,从而保留输出图像的精细特征。实验结果表明,所提算法在Rain800、Rain12、Rain100L和Rain100H公开测试集上的结构相似性分别为0.830、0.968、0.960和0.944,峰值信噪比分别为27.33 dB、35.27 dB、36.79 dB和28.94 dB。所提算法相比于经典和新颖的图像去雨算法,在去除雨纹和恢复背景细节上具有更好的效果。

关键词：深度学习图像去雨多阶段网络 Transformer模块通道注意力机制

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Al-free cladding-layer blue laser diodes with a low aspect ratio in far-field beam pattern

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Journal of Semiconductors 2018年第8期39卷 57-61页

作者： Meixin Feng Qian Sun Jianping Liu Zengcheng Li Yu Zhou Hongwei Gao shuming zhang Hui Yang Key Laboratory of Nano-Devices and Applications Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO) Chinese Academy of Sciences School of Nano Technology and Nano Bionics University of Science and Technology of China

c-plane GaN-based blue laser diodes（LDs） were fabricated with Al-free cladding layers（CLs） and deepened etching depth of mesa structure, so the aspect ratio of the far-field pattern（FFP） of the laser beam can be reduced to as low as 1.7, which is nearly the same as conventional AlGa In P-based red LDs. By using GaN CLs,the radiation angle of the laser beam θ⊥ is only 10.1° in the direction perpendicular to the junction plane. After forming a deeply etched mesa, the beam divergence angle parallel to the junction plane of FFP, θ;, increases from4.9° to 5.8°. After using the modified structure, the operation voltage of LD is effectively reduced by 2 V at an injection current of 50 mA, but the threshold current value increases. The etching damage may be one of the main reasons responsible for the increase of the threshold current.

关键词： Al-free cladding layers far-field beam patterns aspect ratio laser diodes

相山铀矿田西部煌斑岩年代学、地球化学及幔源流体的证据

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中国地质 2024年第3期51卷 898-911页

作者：刘龙张树明饶泽煌张鑫夏寅初万康欧阳军勇吴志春赣东学院江西抚州344000 东华理工大学核资源与环境国家重点实验室江西南昌330013 东华理工大学放射性地质与勘探技术国防重点学科实验室江西南昌330013 江西省核工业地质局261大队江西鹰潭335001

【研究目的】幔源岩浆是探讨深部动力学演化和铀成矿的研究对象,相山铀矿田基性岩脉是探讨区域岩浆演化和铀成矿的关键所在。【研究方法】本文对矿区西部煌斑岩脉进行了系统的岩石学、地质年代学和地球化学综合研究。【研究结果】本区存... 详细信息

【研究目的】幔源岩浆是探讨深部动力学演化和铀成矿的研究对象,相山铀矿田基性岩脉是探讨区域岩浆演化和铀成矿的关键所在。【研究方法】本文对矿区西部煌斑岩脉进行了系统的岩石学、地质年代学和地球化学综合研究。【研究结果】本区存在3期煌斑岩,分别为134 Ma、120~125 Ma和84.5 Ma。该区煌斑岩为钠质碱性煌斑岩,富集LILE和LREE,亏损HFSE,具明显的Ta-Nb-Ti负异常,具有岛弧玄武岩和大陆地壳的微量元素特征。该区煌斑岩为部分熔融和结晶分异共同作用的产物,经历了橄榄石、单斜辉石的结晶分异作用,在岩浆上侵过程中受到明显上地壳物质的混染。该区煌斑岩形成于伸展作用下的板内拉张构造环境,未受到古太平洋板块俯冲作用的影响。其源区应为软流圈亏损地幔与岩石圈富集地幔的混合,且主要体现为软流圈亏损地幔特征。【结论】第一期煌斑岩矿岩时差大,仅为后期铀的沉淀富集提供有利条件;后两期煌斑岩矿岩时差小,不仅为相山矿田铀矿化提供了幔源流体(ΣCO_(2)矿化剂和He),也为铀沉淀富集提供还原障。

关键词：年代学地球化学源区性质煌斑岩相山矿田矿产勘查工程江西