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基于粗-细网络模型分步训练的地震数据重建方法

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吉林大学学报（地球科学版） 2024年第4期54卷 1396-1405页

作者：葛康建王长鹏张春霞张讲社熊登长安大学理学院西安710064 西安交通大学数学与统计学院西安710049 东方地球物理公司物探技术研究中心河北涿州072751

由于地形等复杂条件的限制,叠前地震数据在空间上存在不完整或不规则分布的情况,导致数据出现缺失或混淆等现象。近年来,基于卷积神经网络的方法已经广泛应用于缺失地震数据重建工作。然而一步训练过程的网络模型不足以重建具有宽振幅... 详细信息

由于地形等复杂条件的限制,叠前地震数据在空间上存在不完整或不规则分布的情况,导致数据出现缺失或混淆等现象。近年来,基于卷积神经网络的方法已经广泛应用于缺失地震数据重建工作。然而一步训练过程的网络模型不足以重建具有宽振幅范围的缺失地震数据,低振幅缺失部分的重建结果仍需改进。因此本文提出一种具有分步训练过程的粗-细网络模型。该模型由粗网络和细网络组成,分步恢复宽振幅范围内的缺失地震数据。在细网络中引入离散小波变换代替池化操作,其可逆性在上采样阶段有利于保留细节特征。模型采用混合损失函数重建缺失信号的真实细节。粗网络的初步恢复结果经过掩码操作处理后输入到细网络,细网络进一步精确恢复缺失部分的低振幅信号。实验结果表明,与残差网络(ResNet)、U型网络(U-Net)和多级小波卷积神经网络(MWCNN)的重建方法相比,本文方法在合成数据和真实数据上展现出更卓越的重建性能:在缺失75%的合成数据上,信噪比为18.818 5 dB;在缺失50%的真实数据上,信噪比为12.2551 dB。在消融研究中,本文模型重建的均方误差为1.689 3×10^(-4),信噪比为19.284 6 dB,峰值信噪比为43.743 5 dB,结构相似性为0.984 1,均优于其他三组对照实验。

关键词：粗-细网络混合损失离散小波变换地震数据重建

Low-rank representation based robust face recognition by two-dimensional whitening reconstruction

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Frontiers of Computer Science 2020年第4期14卷 211-213页

作者： Shuo FENG changpeng wang Hong SHU Tingyu ZHANG School of Construction Machinery Chang’an UniversityXi’an710064China School of Science Chang’an UniversityXi’an710064China

1 Introduction and main contributions Recently,low-rank representation(LRR)has been introduced and applied to capture the underlying low-dimensional struc-ture of data in pattern recognition and computer *** could detect the corruptions automatically during data recov-ery under mild conditions[1].In the sense of simultaneously optimizing the data representation,LRR is claimed to well capture the global structure of the data[2].

关键词： computer representation rank

济南市高新技术产业开发区工业用地绩效评估及障碍度研究

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自然资源情报 2024年第7期 22-29页

作者：张宁宁于元芬王长鹏济南市勘察测绘研究院山东济南250101

本研究基于济南市高新技术产业开发区的工业企业实地调查数据,从“经济—社会—生态”视角出发,采用绩效评价模型和障碍度诊断模型,对开发区内的工业用地进行绩效评估与障碍度分析。研究表明,济南市高新技术产业开发区内工业用地绩效属... 详细信息

本研究基于济南市高新技术产业开发区的工业企业实地调查数据,从“经济—社会—生态”视角出发,采用绩效评价模型和障碍度诊断模型,对开发区内的工业用地进行绩效评估与障碍度分析。研究表明,济南市高新技术产业开发区内工业用地绩效属于中低水平,绩效平均值为0.30;影响开发区工业用地绩效最重要的障碍因子是经济效益和社会效益;影响开发区工业用地绩效的主要障碍指标为单位面积产值、单位面积营业收入、单位面积上缴税费、容积率。因此,未来应发挥政府主体作用,积极探索低效用地退出机制,提高开发区土地整体利用绩效水平,同时减弱开发区工业用地绩效主导障碍,注意协调均衡发展,推动开发区工业用地绩效的可持续提升。

关键词：工业用地开发区绩效评估障碍度

基于Copula函数的千米尺度综合干旱指数构建与应用——以重庆市为例

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自然资源遥感 2024年第3期36卷 117-127页

作者：杨辰飞吴田军王长鹏杨丽娟骆剑承张新长安大学理学院西安710064 长安大学土地工程学院西安710064 中国科学院空天信息创新研究院遥感科学国家重点实验室北京100101 中国科学院大学资源与环境学院北京100049

干旱是影响农业生产最大的自然灾害之一,开发综合干旱指数对于评估干旱具有现实意义。该文耦合XGBoost算法降尺度后的土壤水分和降水Z指数数据,在空间上以重庆市行政区县边界分区,时间上以旬为单位分段,基于Copula函数构建千米尺度网格... 详细信息

干旱是影响农业生产最大的自然灾害之一,开发综合干旱指数对于评估干旱具有现实意义。该文耦合XGBoost算法降尺度后的土壤水分和降水Z指数数据,在空间上以重庆市行政区县边界分区,时间上以旬为单位分段,基于Copula函数构建千米尺度网格化的综合干旱指数(meteorology-agriculture composite standardized dranght index,CSDI M-A),评估干旱的时空特征。结果表明,降尺度提高了遥感产品的空间连续性,为后续构建千米尺度的CSDI M-A提供支持;广义极值分布和t位置尺度分布分别适用于拟合重庆市大多数区县土壤水分和降水变量数据分布,Frank-copula函数适用于拟合旬尺度下二元变量的联合分布;基于土壤墒情数据验证构建的CSDI M-A比降水Z指数能更好地反映干旱信息,基于各区县得到CSDI M-A的空间分布与实际旱情资料相符,说明所构建的CSDI M-A可为干旱评估提供参考。

关键词：干旱土壤水分降水Z指数降尺度综合干旱指数

Mechanical Properties of TiN Coating on Nanocrystalline Surface Layer of 304 Stainless Steel

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稀有金属材料与工程 2012年第S1期41卷 85-88页

作者： wang changpeng Zhou Yimin Zhu Xiaodong Fu Tao Ma Shengge Xi An Jiao Tong Univ Sch Life Sci & Technol State Key Lab Mech Behav Mat Xian 710049 Peoples R China Xi An Jiao Tong Univ Minist Educ Key Lab Biomed Informat Engn Xian 710049 Peoples R China Shenzhen 863 Program Mat Surface Technol R&D Ctr Shenzhen 518029 Peoples R China

Surface nanocrystallization(SNC)can markedly improve surface mechanical properties of metallic materials and accelerate thermal diffusion of elemental *** this work we study the effects of SNC on structure and mechanical properties of TiN coating on 304 stainless steel *** steel was subjected to 15 min surface mechanical attrition treatment(SMAT)to obtain a nanocrystalline surface layer with thickness about 30μ*** coating was deposited on the surface nanocrystallized and the coarse-grained steel substrates by multi-arc ion plating.X-ray diffraction shows that TiN(111)orientation of the coating is much reduced due to SNC *** tests show that the nanocrystalline surface layer has obviously increased surface hardness of the coating system;toughness and adhesion of the coating,impact resistance of the coating system are also *** of SNC-hard coating processing over the conventional duplex treatment consisting of thermal diffusion process-hard coating are shortly discussed.

关键词： surface nanocrystallization stainless steel hard coating duplex treatment

双主相混合稀土基RE-Fe-B磁体的磁性能和抗腐蚀性改进

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稀有金属材料与工程 2024年第3期53卷 660-666页

作者：连昕丽周建军李仕林赵院红王长鹏王印刘飞章明左建华白锁刘艳丽李柱柏李永峰内蒙古科技大学理学院内蒙古包头014010 内蒙古科技大学材料与冶金学院内蒙古包头014010 中科院赣江创新研究院江西赣州341000

为了实现稀土资源的平衡应用且降低RE-Fe-B稀土永磁材料的价格,针对混合稀土基永磁材料进行研究,分别采用单、双主相工艺制备了名义成分[(Pr,Nd)_(1-x)MM_(x)]30.3(Fe,Co)balM_(0.73)B_(0.98)(x=0.3,0.5和0.7,质量分数)的磁体,对比研究... 详细信息

为了实现稀土资源的平衡应用且降低RE-Fe-B稀土永磁材料的价格,针对混合稀土基永磁材料进行研究,分别采用单、双主相工艺制备了名义成分[(Pr,Nd)_(1-x)MM_(x)]30.3(Fe,Co)balM_(0.73)B_(0.98)(x=0.3,0.5和0.7,质量分数)的磁体,对比研究其磁性能和抗腐蚀性。研究发现:双主相工艺制备的磁体相比单主相工艺制备的同成分磁体展现了优越的磁性能和抗腐蚀性。当x=0.5,双主相磁体的磁性能为B_(r)=1.308 T,H_(cj)=799.98 kA/m和(BH)_(max)=325.6436 kJ/m^(3),远高于同成分的单主相磁体的性能(B_(r)=1.297 T,H_(cj)=746.8868 kA/m和(BH)_(max)=317.8428 kJ/m^(3))。这种改进源于富稀土相分布的改进以及主相晶粒间和晶粒内部耦合作用的增强。当双主相磁体暴露在湿热环境下时,磁体中不仅存在富稀土相腐蚀,也存在主相晶粒的腐蚀成粉现象,这主要是由于富稀土相与水蒸气和氧气反应时产生氢气,导致主相晶粒被氢化,由于主相晶粒间和晶粒内部的镧铈分布差异,产生大的应力,导致其表现出区别于单主相磁体的腐蚀行为。

关键词：混合稀土双主相工艺磁性能抗腐蚀性稀土的非均匀分布

Microstructure Evolution and Grain Coarsening Behaviour During Partial Remelting of Cyclic Extrusion Compression Formed AZ61 Magnesium Alloy

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Acta Metallurgica Sinica(English Letters) 2013年第2期26卷 149-156页

作者： changpeng wang Huasheng MEI Rongqiang LI Difan LI Ling wang Jie LIU Zehui HUA Lijin ZHAO Feifei PEN Hui LI No.59 Institute of China Ordnance Industry

The effects of CEC passes, isothermal holding time and reheating temperature on the microstructure evolution and grain coarsening behaviour of AZ61 magnesium alloy produced by the recrystallisation and partialmelting （RAP） process were investigated. Before partial remelting, as-cast AZ61 alloy was deformed by cyclic extrusion compression （CEC） with one pass and two pass at 330 ℃. After CEC, the microstructure consisted of unrecrystallized grains and deformed eutectic compounds. Increasing isothermal holding time resulted in the formation of spheroidal grains surrounded by liquid films. With increasing the isothermal holding time, the solid grain size increased and the degree of spheroidization was improved. With increasing the reheating temperature, namely increasing liquid fraction, the solid grain size obviously decreased during the period from 560 ℃ to 570 ℃ and then slightly increased after 570 ℃, while the shape factor increased monotonously. During partial remelting, increasing reheating temperature can properly short the isothermal holding time to obtain fine structure. Moreover, increasing the numbers of CEC passes could produce finer semi-solid microstructure. The coarsening behavior of solid grains in the semi-solid state obeys Ostwald ripening and grain coalescence mechanisms. The coarsening rate constant, K, 595 ℃. After CEC plus partial remelting, the ideal and fine was suitable for thixoforming. was 80μm^3.s^-1 for samples partially remelted at semi-solid state structure can be obtained, which

关键词： AZ61 magnesium alloy Cyclic extrusion compression Microstructureevolution Grain coarsening

Degradation mechanisms and stabilization strategies of ruthenium-based catalysts for OER in the proton exchange membrane water electrolyzer

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Progress in Natural Science:Materials International 2024年第1期34卷 207-222页

作者： Ming Yang Hongxiang Wu Zhaoping Shi Yibo wang Jiahao Yang Jing Ni Pengbo wang Yuqing Cheng Ziang wang Meiling Xiao changpeng Liu Wei Xing Laboratory of Advanced Power Sources Changchun Institute of Applied Chemistry Chinese Academy of Sciences School of Applied Chemistry and Engineering University of Science and Technology of China Jilin Province Key Laboratory of Low Carbon Chemical Power Sources State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Designing economical oxygen evolution reaction(OER) electrocatalysts with high activity and long-term stability is essential to promote the scale-up applications of proton exchange membrane water electrolyzer(PEMWE) for hydrogen production. Ruthenium(Ru)-based materials with high intrinsic activity are hailed as the most promising catalysts, but still infeasible for practical application considering their long unresolved poor stability(only dozens of lifespan). Thus, tremendous efforts have been devoted to uncovering the degradation mechanisms and developing stabilization strategies for the Ru-based catalysts. In this review, starting from summarizing the fundamental understanding of deactivation mechanisms, a picture of the stability issue of Ru-based catalysts is proposed, which is followed by a detailed discussion on the recently developed strategies and progress made on enhancing durability. Finally, insights on the prospects for the future development of stable and practical Rubased OER catalysts are provided.

关键词： OER Ru-based catalysts PEMWE Degradation mechanisms Stabilization strategies

Stabilizing high-efficiency iridium single atoms via lattice confinement for acidic oxygen evolution

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Nano Research 2024年第4期17卷 2492-2498页

作者： Yibo wang Jiadong Jiang Zhaoping Shi Hongxiang Wu Jiahao Yang Pengbo wang Shuai Hou Meiling Xiao Junjie Ge changpeng Liu Wei Xing Laboratory of Advanced Power Sources Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026.China State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Jilin Province Key Laboratory of Low Carbon Chemical Power Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Physics and Technology for Advanced Batteries Ministry of EducationCollege of PhysicsJilin UniversityChangchun 130012China

Stable and efficient single atom catalysts(SACs)are highly desirable yet challenging in catalyzing acidic oxygen evolution reaction(OER).Herein,we report a novel iridium single atom catalyst structure,with atomic Ir doped in tetragonal PdO matrix(IrSAs-PdO)via a lattice-confined *** optimized IrSAs-PdO-0.10 exhibited remarkable OER activity with an overpotential of 277 mV at 10 mA·cm^(-2) and long-term stability of 1000 h in 0.5 M H_(2)SO_(4).Furthermore,the turnover frequency attains 1.6 s^(-1) at an overpotential of 300 mV with a 24-fold increase in the intrinsic *** high activity originates from isolated iridium sites with low valence states and decreased Ir–O bonding covalency,and the excellent stability is a result of the effective confinement of iridium sites by Ir–O–Pd ***,we demonstrated for the first time that SACs have great potential in realizing ultralow loading of iridium(as low as microgram per square center meter level)in a practical water electrolyzer.

关键词： lattice confinement iridium single atoms ultralow iridium loading acidic oxygen evolution proton exchange membrane water electrolysis