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Time-Domain Full Waveform Inversion Using the Gradient Preconditioning Based on Transmitted Wave Energy

Journal of Ocean University of China 2019年第4期18卷 859-867页

作者： SONG Peng TAN Jun LIU Zhaolun ZHANG Xiaobo LIU Baohua YU Kaiben LI Jinshan XIA Dongming xie chuang College of Marine Geo-Sciences Ocean University of China Qingdao 266100 China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Qingdao 266100 China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of Education Ocean University of China Qingdao 266100 China Physical Science and Engineering Division (PSE) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia National Deep Sea Center Qingdao 266100 China

The gradient preconditioning approach based on seismic wave energy can effectively avoid the huge memory consumption of the gradient preconditioning algorithms based on the Hessian matrix. However, the accuracy of this approach is prone to be influ- enced by the energy of reflected waves. To tackle this problem, the paper proposes a new gradient preconditioning method based on the energy of transmitted waves. The approach scales the gradient through a precondition factor, which is calculated by the ‘ap- proximate transmission wavefield’ simulation based on the nonreflecting acoustic wave equation. The method requires no computing nor storing of the Hessian matrix and its inverse matrix. Furthermore, the proposed method can effectively eliminate the effects of geometric spreading and disproportionality in the gradient illumination. The results of model experiments show that the time-domain full waveform inversion (FWI) using the gradient preconditioning based on transmitted wave energy can achieve higher inversion accuracy for deep high-velocity bodies and their underlying strata in comparison with the one using the gradient preconditioning based on seismic wave energy. The field marine seismic data test shows that our proposed method is also highly applicable to the FWI of field marine seismic data.

关键词： full waveform inversion gradient preconditioning transmitted wave nonreflecting acoustic wave equation

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Internal Multiple Prediction Based on Imaging Profile Prediction and Kirchhoff Demigration

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Journal of Ocean University of China 2019年第6期18卷 1360-1370页

作者： QIU Binhuang TAN Jun DAN Zhiwei YU Jiashun YAN Hongyan LIU Baohua YU Kaiben SONG Peng xie chuang College of Geophysics Chengdu University of TechnologyChengdu 610059China Laboratory for Marine Mineral Resource Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China CNOOC EnerTech-Drilling&Production Co. Data Processing Co.Zhanjiang 524057China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationQingdao 266100China College of Marine Geo-sciences Ocean University of ChinaQingdao 266100China National Deep Sea Center Qingdao 266100China

This paper introduces an internal multiple prediction method based on imaging profile prediction and Kirchhoff ***,based on an inputted prestack time migration profile,the method predicts the prestack time migration profile that only includes internal multiples by inverse scattering series ***,the method uses velocity-weighted Kirchhoff demigration to create shot gathers that contains only internal *** multiple prediction based on the prestack time migration profile effectively reduces the computational cost of multiple predictions,and the internal-multiple shot gathers created by Kirchhoff demigration remarkably reduces the complexity of the practical *** multiple elimination can be conducted through the combined adaptive multiple subtraction based on event *** and field data tests show that the method effectively predicts internal multiples and possesses considerable potential in field data processing,particularly in areas where internal multiples develop seriously.

关键词： internal multiple prediction inverse scattering series method Kirchhoff demigration Kirchhoff prestack time migration

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Gelation Mechanism of Erythromycin Ethylsuccinate During Crystallization

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Transactions of Tianjin University 2019年第2期25卷 110-117页

作者： Xiandong Su Zhenguo Gao Ying Bao Miao Guan Sohrab Rohani Qiuxiang Yin Hongxun Hao chuang xie Jingkang Wang School of Chemical Engineering and Technology Tianjin University Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin) Department of Chemical and Biochemical Engineering Western University

In this paper, the gelation mechanism of erythromycin ethylsuccinate(EES) during crystallization is investigated for the first time. The generated semisolid gel-like phase exhibited a 3D fibrillar network morphology and the typical rheological properties of gels. The fibers inside the gel-like phase were confirmed to be new types of EES solvates using powder X-ray diffraction, thermogravimetric analysis/differential scanning calorimetry, and gas chromatography. The gelation and crystallization regions in EES-1-propanol solid–liquid phase diagram were determined. Analyses of solvent parameters showed that moderate solvent polarity may promote EES gelation. Fourier transform infrared spectra, nuclear magnetic resonance spectra, and scanning electron microscopy analyses indicated that through intermolecular hydrogen bonds, EES and solvent molecules assembled into fibers via crystallographic mismatch branching growth. The fibers intertwined into a 3D network microstructure and formed a gel-like phase, completely immobilizing the solution.

关键词： Gelation Solvate Crystallization Phase diagram Molecular self-assembly

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Compounds from the flowers and fruits of Abelmoschus esculentus (L.) Moench

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Asian Journal of Traditional Medicines 2021年第5期16卷 269-275页

作者： Sihui Mi Rui Guo chuang xie Xiaoxiao Huang Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug Research&Development Liaoning ProvinceSchool of Traditional Chinese Materia MedicaShenyang Pharmaceutical UniversityShenyang 110016China

The Abelmoschus esculentus(L.)Moench was previously reported to have various *** fractionation yielded from the ethanolic extract of the *** ten compounds,including four alkaloids(4-6,8)and six phenolic acids(1-3,7,9-10).The structures of the compounds were elucidated through extensive spectra analyses and comparison of the experimental data with reported *** is worth mentioning that compounds 1,2 and 5-10 were isolated from Abelmoschus esculentus(L.)for the first time.

关键词： Abelmoschus esculentus(L.)Moench phenolic acids alkaloids

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Pedestrian Detection and Location Algorithm Based on Deep Learning

Pedestrian Detection and Location Algorithm Based on Deep Le...

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作者： xie chuang Li Pin Sun Yurong Department of Science Central South University of Forestry and Technology

This paper studies the insufficient extracted image feature in CNN basic network towards large model parameters quantity in convolutional neural network-based target detection ***,it analyzes calculating method and parameter quantity of separable convolution and standard convolution,and processes original image through increasing sampling layer and blocking area extraction layer on ***,original image will be sampled with two different ratios to form image pyramid sequence and splice two-layered pyramid image in order to guarantee the same original image ***,a better learning ability in network can be enhanced under condition without increasing networked scale through multi-scaled training *** experiment shows target detection algorithm in this paper cannot only be superior to traditional algorithm but it can also be superior to YOLO model and SSD model in comprehensive performance.

关键词： pedestrian detection CNN deep learning YOLO

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单溶剂体系中CdSe纳米晶体的形貌调控研究

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人工晶体学报 2009年第1期38卷 215-220页

作者：谢闯陈巍王静康天津大学化工学院天津300072 天津经济技术开发区企业博士后工作站天津300457

采用非水溶液方法,分别在十六胺(HDA)或邻苯二甲酸辛酯(DOP)的单溶剂体系中,通过调节前体加入速度和反应温度制备出六角形、多臂、短棒、长棒状以及四脚架形CdSe纳米晶体,并用透射电镜(TEM)对所得产品进行了表征。结果表明,前体的过饱... 详细信息

采用非水溶液方法,分别在十六胺(HDA)或邻苯二甲酸辛酯(DOP)的单溶剂体系中,通过调节前体加入速度和反应温度制备出六角形、多臂、短棒、长棒状以及四脚架形CdSe纳米晶体,并用透射电镜(TEM)对所得产品进行了表征。结果表明,前体的过饱和度强烈地影响CdSe纳米晶体的形貌,过饱和度的提高有导致六方纤锌矿结构(011-)方向上择向生长的趋势;两种单溶剂体系中在CdSe纳米晶体的形貌调控上有不同的影响;200℃不利于得到高质量的CdSe纳米晶体。

关键词： CdSe 纳米晶体单溶剂体系形貌控制

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Concurrent Structural and Electronic Phase Transitions in V_(2)O_(3)Thin Films with Sharp Resistivity Change

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Chinese Physics Letters 2021年第7期38卷 79-84页

作者： chuang xie Ling Hu Ran-Ran Zhang Shun-Jin Zhu Min Zhu Ren-Huai Wei Xian-Wu Tang Wen-Hai Song Xue-Bin Zhu Yu-Ping Sun Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601China Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China High Magnetic Field Laboratory HFIPSChinese Academy of SciencesHefei 230031China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

The relationship between structural and electronic phase transitions in V_(2)O_(3)thin films is of critical importance for understanding of the mechanism behind metal–insulator transition(MIT)and related technological *** being extensively studied,there are currently no clear consensus and picture of the relation between structural and electronic phase transitions so *** V_(2)O_(3)thin films grown on r-plane Al2O3 substrates,which exhibit abrupt MIT and structural phase transition,we show that the electronic phase transition occurs concurrently with the structural phase transition as revealed by the electrical transport and Raman spectra *** result provides experimental evidence for clarifying this issue,which could form the basis of theoretical studies as well as technological applications in V_(2)O_(3).

关键词： structural transition Transition

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一种制备CdSe纳米晶体的方法

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天津大学学报 2007年第3期40卷 280-284页

作者：谢闯陈巍王静康天津大学化工学院天津300072

CdSe纳米晶体因其独特的新颖性质具有广阔应用前景,但常用的非水相方法所用的原料,如三正辛基氧化膦等,价格昂贵且毒性大．为此,引入了价格便宜、环境友好的新溶剂A,在其中合成了CdSe纳米晶体,并利用紫外可见光谱、荧光发射光谱、透射... 详细信息

CdSe纳米晶体因其独特的新颖性质具有广阔应用前景,但常用的非水相方法所用的原料,如三正辛基氧化膦等,价格昂贵且毒性大．为此,引入了价格便宜、环境友好的新溶剂A,在其中合成了CdSe纳米晶体,并利用紫外可见光谱、荧光发射光谱、透射电镜、能量分散X射线谱和X射线衍射对得到的纳米晶体进行了表征．结果表明,在新溶剂中合成的CdSe纳米晶体粒度均匀,粒径可控,具有高的结晶度和良好的光学性质．新溶剂A降低了合成成本,使合成更加符合绿色化学的原则．

关键词：硒化镉半导体纳米晶体非水相方法绿色合成

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Low-frequency swell noise suppression based on U-Net

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Applied Geophysics 2020年第3期17卷 419-431页

作者： Zhang Rui-qi Song Peng Liu Bao-hua Zhang Xiao-bo Tan Jun Zou Zhi-hui xie chuang Wang Shao-wen College of Marine Geosciences Ocean University of ChinaQingdao 266100China. Laboratory for MMR Qingdao National Laboratory for Marine Science and TechnologyQingdao 266100China. Key Laboratory of Submarine Geoscience and Prospecting Techniques Ministry of EducationQingdao 266100China National Deep Sea Center Qingdao 266237China.

Low-frequency band-shaped swell noise with strong amplitude is common in marine seismic *** conventional high-pass fi ltering algorithm widely used to suppress swell noise often results in serious damage of effective *** paper introduces the residual learning strategy of denoising convolutional neural network(DnCNN)into a U-shaped convolutional neural network(U-Net)to develop a new U-Net with more generalization,which can eliminate low-frequency swell noise with high *** results of both model date tests and real data processing show that the new U-Net is capable of effi cient learning and high-precision noise removal,and can avoid the overfi tting problem which is very common in conventional neural network *** new U-Net can also be generalized to some extent and can eff ectively preserve low-frequency eff ective *** with the conventional high-pass fi ltering method commonly used in the industry,the new U-Net can eliminate low-frequency swell noise with higher precision while eff ectively preserving low-frequency eff ective information,which is of great signifi cance for subsequent processing such as amplitude-preserving imaging and full waveform inversion.

关键词： U-Net swell noise noise attenuation residual learning generalization

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壳聚糖亚微粒稳定的Pickering乳液制备pH响应微胶囊

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天津大学学报（自然科学与工程技术版） 2019年第4期52卷 368-374页

作者：张欣谢闯陈峰王静康天津大学化工学院天津300072 天津化学化工协同创新中心天津300072 天津药业研究院有限公司天津300000

采用离子凝胶法制备了壳聚糖-三聚磷酸钠(CS-TPP)亚微米颗粒,并以其为稳定剂,制备了内含聚乳酸-羟基乙酸共聚物(PLGA)和布洛芬(IBU)药物的o/w型Pickering乳液;采用溶剂挥发法制备了CS-TPP亚微米颗粒包覆的载药微胶囊,并通过静电作用包... 详细信息

采用离子凝胶法制备了壳聚糖-三聚磷酸钠(CS-TPP)亚微米颗粒,并以其为稳定剂,制备了内含聚乳酸-羟基乙酸共聚物(PLGA)和布洛芬(IBU)药物的o/w型Pickering乳液;采用溶剂挥发法制备了CS-TPP亚微米颗粒包覆的载药微胶囊,并通过静电作用包覆羧甲基纤维素钠(CMC).利用SEM、光学显微镜、荧光共聚焦显微镜、红外光谱等对载药微胶囊进行了表征.以IBU为模型药物,在模拟胃液(SGF,pH=1.2)和模拟肠液(SIF,pH=6.8)中进行载药微胶囊的体外药物释放实验.结果表明:所得载药微胶囊在SIF中释放速率为其在SGF中的约12倍,表现出良好的pH响应性.

关键词： pH响应载药微胶囊壳聚糖-三聚磷酸钠 Pickering乳液

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