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SegNet-based first-break picking via seismic waveform classification directly from shot gathers with sparsely distributed traces

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Petroleum Science 2022年第1期19卷 162-179页

作者： San-Yi yuan Yue Zhao Tao Xie Jie Qi Shang-Xu Wang State Key Laboratory of Petroleum Resources and Prospecting CNPC Key Laboratory of Geophysical ExplorationChina University of PetroleumBeijing 102249China China Oilfield Services Ltd. TangguTianjin 300452China University of Oklahoma ConocoPhillips School of Geology and GeophysicsNormanOKUSA

Manually picking regularly and densely distributed first breaks(FBs)are critical for shallow velocitymodel building in seismic data ***,it is time *** employ the fullyconvolutional Seg Net to address this issue and present a fast automatic seismic waveform classification method to pick densely-sampled FBs directly from common-shot gathers with sparsely distributed *** feeding a large number of representative shot gathers with missing traces and the corresponding binary labels segmented by manually interpreted fully-sampled FBs,we can obtain a welltrained Seg Net *** any unseen gather including the one with irregular trace spacing is inputted,the Seg Net can output the probability distribution of different categories for waveform *** FBs can be picked by locating the boundaries between one class on post-FBs data and the other on pre-FBs *** land datasets with each over 2000 shots are adopted to illustrate that one well-trained 25-layer Seg Net can favorably classify waveform and further pick fully-sampled FBs verified by the manually-derived ones,even when the proportion of randomly missing traces reaches50%,21 traces are missing consecutively,or traces are missing regularly.

关键词： First-break picking Deep learning Irregular seismic data Waveform classification

Curcumin Interferes with TGF-β1-Induced Fibrosis in NRK-49F Cells by Reversing ADAMTS18 Gene Methylation

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Chinese Journal of Integrative Medicine 2024年第7期30卷 600-607页

作者： XU Ben ZHANG Jia-en YE Lin yuan Chang-wei Department of Urology Peking University First Hospital and Institute of UrologyPeking UniversityNational Urological Cancer CenterBeijing100034China

Objective To explore the molecular mechanism by which curcumin affects renal interstitial fibrosis(RIF)progression by regulating ADAM metallopeptidase with thrombospondin type 1 motif 18(ADAMTS18)*** NRK-49F cells RIF model were induced with transforming growth factorβ1(TGF-β1).Effects of different concentrations of curcumin(0,10,20,and 30μmol/L)on cell proliferation,cell cycle,cell apoptosis as well as cyclin D1 expression were analyzed by cell counting kit-8,flow cytometry and Western blot,***18 methylation levels were determined by methylation-specific polymerase chain ***18,fibronectin(FN),type I collagen(Col-I)and alpha-smooth muscle actin(α-SMA)mRNA and protein expressions were analyzed by real-time PCR(RT-PCR)and Western blot,***,cells were treated with 50 mmol/L 5-aza-2′-deoxycytidine(5-aza-dC,demethylation agent)for 72 *** of curcumin on extracellular matrix(ECM)deposition was evaluated by immunochemical staining and Western ***-49F cells were transfected with ADAMTS18 small interfering RNA and grouped into a normal control,ADAMTS18-knock-out(KO),and ADAMTS18-KO+30μmol/L curcumin groups,and whether curcumin can reverse the effect of ADAMTS18 knockdown on RIF was *** Compared with the control group,TGF-β1 significantly inhibited the proliferation of NRK-49F cells,blocked the G1/G0 phase,promoted cell apoptosis and inhibited cyclin D1 expression(P<0.01).Among the different concentrations of curcumin,30μmol/L curcumin significantly reversed these processes(P<0.01).Immunochemical staining and Western blot results showed that curcumin significantly inhibited the deposition of FN,Col-I andα-SMA(P<0.01).Curcumin and 5-zaz-dC had synergistic effects,promoting ADAMTS18 expression,removing ADAMTS18 methylation,and reducing ECM ***18 knockdown promoted ECM accumulation,and curcumin reversed this process(P<0.01).Conclusion TGF-β1-induced fibrosis in NRK-49F ***

关键词： renal fibrosis curcumin Chinese medicine ADAMTS18 methylation modification

FDI Flows between China and ASEAN:Emerging Factors and Prospect

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China & World Economy 2006年第6期14卷 98-106页

作者： yuan Shu Kaisheng Zeng Professor Sun Yat-Sen University China

Economic relations between China and ASEAN have further intensified since the 1990s. Foreign direct investment (FDI) flows between the two economic giants have reached a new high, attracting the attention of policy-makers and economists. The present paper investigates recent contextual changes and identifies some significant emerging factors that exert influence on the flows of FDl between China and ASEAN. This paper also analyzes the development trend of FDI between the two economies, and it is found that the FDl flows are at a historical turning point.

关键词： ASEAN China foreign direct investment regional economy

Algebraic form and analysis of SIR epidemic dynamics over probabilistic dynamic networks

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Control Theory and Technology 2023年第4期21卷 602-611页

作者： Hongxing yuan Zengqiang Chen Zhipeng Zhang Rui Zhu Zhongxin Liu College of Artificial Intelligence Nankai UniversityTianjin300350China School of Artificial Intelligence Tiangong UniversityTianjin300387China

The outbreak of corona virus disease 2019 has profoundly affected people’s way of *** is increasingly necessary to investigate epidemics over social *** paper studies susceptible-infected-removed(SIR)epidemics via the semi-tensor ***,a formal susceptible-infected-removed epidemic dynamic model over probabilistic dynamic networks(SIRED-PDN)is *** on an evolutionary rule,the algebraic form for the dynamics of individual states and network topologies is given,***,the SIRED-PDN can be described by a probabilistic mix-valued logical *** providing an algorithm,all possible final spreading equilibria can be obtained for any given initial epidemic state and network topology by seeking attractors of the *** the shortest time for all possible initial epidemic state and network topology profiles to evolve to the final spreading equilibria can be obtained by seeking the transient time of the ***,an illustrative example is given to show the effectiveness of our model.

关键词： SIR epidemic Probabilistic dynamic networks Final spreading equilibria Semi-tensor product of matrices Algebraic form

Large-scale extraction of check dams and silted fields on the Chinese loess plateau using ensemble learning models

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International Soil and Water Conservation Research 2024年第3期12卷 548-564页

作者： Yunfei Li Jianlin Zhao Ke yuan Gebeyehu Taye Long Li Department of Geology Engineering and Geomatics Changan UniversityYantalu 126Xian710054China Department of Land Resources Management and Environmental Protection Mekelle UniversityP.O.Box231MekellEthiopia Collaborative Innovation Center of Territorial Space Safety&Management School of Public Policy&ManagementChina University of Mining and TechnologyDaxue Road 1Xuzhou221116China Department of Geography Vrje Universiteit BrusselPleinlaan 21050BrusselsBelgium

Check dams have been widely constructed in the Chinese Loess Plateau and has played an important role in controlling soil loss during last 70 ***,the large-scale and automatic mapping of the check dams and the resulting silted fields are *** this study,we present a novel methodological framework to extract silted fields and to estimate the location of the check dams at a pixel level in the Wuding River catchment by remote sensing and ensemble learning *** random under-sampling method and 23 features were used to train and validate three ensemble learning models,namely Random Forest,Extreme Gradient Boosting and EasyEnsemble,based on a large number of *** established optimal model was then applied to the whole study area to map check dams and silted *** results indicate that the imbalance ratio of the samples has a significant impact on the performance of the *** of the results on the testing set show that the F1-score of silted fields of three models is higher than 0.75 at the pixel ***,we produced a map of silted fields and check dams at 10 m-spatial resolution by the optimal model with an accuracy of ca.90%at the object *** proposed framework can be used for the large-scale and high-precision mapping of check dams and silted fields,which is of great significance for the monitoring and management of the dynamics of check dams and the quantitative evaluation of their eco-environmental benefits.

关键词： Sited field Ensemble learning Random under-sampling Imbalanced classification Chinese loess plateau

Causes of a Typical Southern Flood and Northern Drought Event in 2015 over Eastern China

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Advances in Atmospheric Sciences 2023年第11期40卷 2092-2107,I0014,I0015页

作者： Zhuoyuan LI Qing YANG Dian yuan Er LU Zhuguo MA Key Laboratory of Meteorological Disaster Ministry of Education(KLME)Joint International Research Laboratory of Climate and Environment Change(ILCEC)Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science and TechnologyNanjing 210044China Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Xiongan Institute of Innovation Chinese Academy of SciencesXiongan New Area 071800China

The spatial distribution of summer precipitation anomalies over eastern China often shows a dipole pattern,with anti-phased precipitation anomalies between southern China and northern China,known as the“southern flooding and northern drought”(SF-ND)*** 2015,China experienced heavy rainfall in the south and the worst drought since 1979 in the north,which caused huge social and economic *** reanalysis data,the atmospheric circulation anomalies and possible mechanisms related to the summer precipitation anomalies in 2015 were *** results showed that both El Niño and certain atmospheric teleconnections,including the Pacific Japan/East Asia Pacific(PJ/EAP),Eurasia pattern(EU),British–Baikal Corridor pattern(BBC),and Silk Road mode(SR),contributed to the dipole pattern of precipitation *** combination of these factors caused a southwards shift of the western Pacific subtropical high(WPSH)and a weakening of the East Asian summer ***,it was difficult for the monsoon front and associated rain band to migrate northwards,which meant that less precipitation occurred in northern China while more precipitation occurred in southern *** resulted in the SF-ND ***,further analysis revealed that global sea surface temperature anomalies(SSTAs)or sea-ice anomalies were key to stimulating these atmospheric teleconnections.

关键词： drought flood El Niño atmospheric teleconnection sea surface temperature anomaly

Robust Attitude Tracking Control Scheme for Flexible Spacecraft with Vibration Suspension

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Robust Attitude Tracking Control Scheme for Flexible Spacecr...

Preparation of B_(2)O_(3)/SBA-15 and Application as Matrix Component in Nickel-Tolerant Fluid Catalytic Cracking Catalyst

第25届中国控制与决策会议

作者： SHI Xiaoping yuan Guoping Control and Simulation Center Harbin Institute of Technology

ISBN: (纸本)9781467355339

In this paper, a novel robust control algorithm is proposed to carry out large-angle attitude tracking control of a flexible spacecraft subject to external disturbances. An adaptive scheme based on neural network system is designed to ensure the actual attitude to track the command input in the presence of external disturbances. To reduce adverse effects caused by the elastic vibration on the closed-loop performance of the flexible spacecraft, an active vibration controller with independent modal space method is added to the overall control algorithm. Moreover, for achieving perfect control performance and constructing systematic tuning procedure for controller parameters, genetic algorithm is applied to search the optimal values of active vibration controller. Stability of the whole closed-loop system is proved via Laypunov theory and simulation results confirm the effectiveness of the proposed method.

关键词： Attitude Maneuver Flexible Spacecraft Active Vibration Control Neural Network Genetic Algorithm

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China Petroleum Processing & Petrochemical Technology 2023年第1期25卷 144-150页

作者： yuan Chengyuan Ju Guannan Chen Qiang Yan Tao Li Zhongfu School of Materials Science and Engineering Shandong University of TechnologyZiboShandong 255000China Shanxi Tengmao Technology Co. Ltd.HejinShanxi 043300China

Fluid catalytic cracking(FCC)is still a key process in the modern refining industry,in which nickel contamination of the FCC catalyst can significantly increase the dry gas and coke yields and thus seriously affect the stability of the FCC ***,in this work,B_(2)O_(3)-modified SBA-15 molecular sieves(B_(2)O_(3)/SBA-15)with different B_(2)O_(3) contents were prepared,characterized,and further used as matrix component in the preparation of Ni-tolerant FCC *** characterization results indicated that the B_(2)O_(3)/SBA-15 samples possessed excellent Ni passivation ability and kept the characteristic structure of the parent SBA-15 such as highly ordered mesopores,large surface area,and high pore volume,which enabled the B_(2)O_(3)/SBA-15 sample to greatly improve the Ni tolerance of the prepared FCC *** heavy oil catalytic cracking tests indicated that,under the same Ni contamination conditions,the dry gas,coke,and heavy oil yields of the FCC catalyst containing B_(2)O_(3)/SBA-15 decreased by 0.92%,1.65%,and 1.26%,respectively,compared with those of conventional FCC catalyst,while the total liquid yield increased by 3.83%.

关键词： Ni tolerance B_(2)O_(3)modification SBA-15 FCC catalyst

Feature Construction and Identification of Convective Wind from Doppler Radar Data

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Journal of Meteorological Research 2022年第1期36卷 79-92页

作者： Yuchen BAO Juntao XUE Di WANG Yue yuan Ping WANG School of Electrical and Information Engineering Tianjin UniversityTianjin 300072

Convective wind is one of the common types of severe convective *** and Forecasting of convective wind are *** this paper,five kinds of features are firstly constructed from characteristics of typical convective wind-related echo phenomena based on Doppler radar *** features include storm motion,high-value reflectivity,high-value velocity,velocity shear,and velocity texture.A severe convectiye wind(SCW)identification model is then built by applying the above features to the random forest *** convective wind samples collected over 13 cities of China in June-August 2016,it is found that the probability of detection(POD)of SCW is 78.9%,the false alarm ratio(FAR)is 26.4%,and the critical success index(CSI)is 61.5%.For the convective wind samples that cary typical echo features,the POD,FAR,and CSI range from 89.4%to 99.3%,4.2%to 16.0%,and 76.4%to95.1%,***,the POD and negative-case POD of samples without typical echo features are 66.8%and 85.4%,*** experimental results demonstrate that the SCW identification model can classify nonSCW effectively,and performs better with SCW samples carrying typical echo features than without.

关键词： convective wind identification radial velocity shear features texture features machine learning