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Seismic data reconstruction based on low dimensional manifold model

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Petroleum Science 2022年第2期19卷 518-533页

作者： Nan-ying Lan Fan-Chang Zhang xing-Yao yin School of Geosciences China University of Petroleum(East China)QingdaoShandong 266580China

Seismic data reconstruction is an essential and yet fundamental step in seismic data processing workflow,which is of profound significance to improve migration imaging quality,multiple suppression effect,and seismic inversion *** methods play a central role in solving the underdetermined inverse problem of seismic data *** this paper,a novel regularization approach is proposed,the low dimensional manifold model(LDMM),for reconstructing the missing seismic *** work relies on the fact that seismic patches always occupy a low dimensional ***,we exploit the dimension of the seismic patches manifold as a regularization term in the reconstruction problem,and reconstruct the missing seismic data by enforcing low dimensionality on this *** crucial procedure of the proposed method is to solve the dimension of the patches *** this,we adopt an efficient dimensionality calculation method based on low-rank approximation,which provides a reliable safeguard to enforce the constraints in the reconstruction *** experiments performed on synthetic and field seismic data demonstrate that,compared with the curvelet-based sparsity-promoting L1-norm minimization method and the multichannel singular spectrum analysis method,the proposed method obtains state-of-the-art reconstruction results.

关键词： Seismic data reconstruction Low dimensional manifold model Regularization Low-rank approximation

Fluid discrimination incorporating amplitude variation with angle inversion and squirt flow of the fluid

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Petroleum Science 2022年第4期19卷 1592-1604页

作者： Yu-Rong Wang Zhao-Yun Zong xing-Yao yin China University of Petroleum QingdaoShandong266580China Shandong Provincial Key Laboratory of Deep Oil and Gas QingdaoShandong266580China Pilot National Laboratory for Marine Science and Technology(Qingdao) Shandong266580China

Pre-stack seismic inversion is an important method for fluid identification and reservoir characterization in exploration geophysics. In this study, an effective fluid factor is initially established based on Biot poroelastic theory, and a pre-stack seismic inversion method based on Bayesian framework is used to implement the fluid identification. Compared with conventional elastic parameters, fluid factors are more sensitive to oil and gas. However, the coupling effect between rock porosity and fluid content is not considered in conventional fluid factors, which may lead to fuzzy fluid identification results. In addition,existing fluid factors do not adequately consider the physical mechanisms of fluid content, such as squirt flow between cracks and pores. Therefore, we propose a squirt fluid factor(SFF) that minimizes the fluid and pore mixing effects and takes into account the squirt flow. On this basis, a novel P-wave reflection coefficient equation is derived, and the squirt fluid factor is estimated by amplitude variation with offset(AVO) inversion method. The new reflection coefficient equation has sufficient accuracy and can be utilized to estimate the parameters. The effectiveness and superiority of the proposed method in fluid identification are verified by the synthetic and field examples.

关键词： Fluid discrimination Poroelasticity theory Linearized seismic reflectivity Pre-stack seismic inversion Squirt flow of fluid

Estimation of daily PM2.5 concentration and its relationship with meteorological conditions in Beijing

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Journal of Environmental Sciences 2016年第10期28卷 161-168页

作者： qian yin Jinfeng Wang Maogui Hu Hoting Wong LREIS Institute of Geographic Sciences and Nature Resources Research Chinese Academy of Sciences Beijing 100101 China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023 China

When investigating the impact of air pollution on health, particulate matter less than 2.5μm in aerodynamic diameter （PM2.5） is considered more harrnful than particulates of other sizes. Therefore, studies of PM2.5 have attracted more attention. Beijing, the capital of China, is notorious for its serious air pollution problem, an issue which has been of great concern to the residents, government, and related institutes for decades. However, in China, significantly less time has been devoted to observing PM2.5 than for PM10. Especially before 2013, the density of the PM2.5 ground observation network was relatively low, and the distribution of observation stations was uneven. One solution is to estimate PM2.5 concentrations from the existing data on PM10. In the present study, by analyzing the relationship between the concentrations of PM2.5 and PM10, and the meteorological conditions for each season in Beijing from 2008 to 2014, a U-shaped relationship was found between the daily maximum wind speed and the daily PM concentration, including both PM2.5 and PM10. That is, the relationship between wind speed and PM concentration is not a simple positive or negative correlation in these wind directions; their relationship has a complex effect, with higher PM at low and high wind than for moderate winds. Additionally, in contrast to previous studies, we found that the PM2.5/PM10 ratio is proportional to the mean relative humidity （MRH）. According to this relationship, for each season we established a multiple nonlinear regression （MNLR） model to estimate the PM2.5 concentrations of the missing periods.

关键词： PM10 concentrationPM2.5 concentration estimationWind speedWind direction

HIV Cure and HIV Reservoirs

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Biomedical and Environmental Sciences 2014年第6期27卷 478-480页

作者： yin qian qian Shao Yi Ming MA Li ying State Key Laboratory for Infection Disease Prevention and Control National Center for AIDS/STD Control and Prevention (NCAIDS) Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseas Chinese Center for Disease Control and Prevention (China-CDC)

The success of combined antiretroviral therapy （cART） has dramatically improved the clinical outcomes of HIV infection and made HIV infection a chronic disease. Nonetheless, cART alone cannot eliminate viral reservoirs and fully recover patients＇ health, so the patients have to receive this treatment for lifetime. Therefore, researchers have focused their efforts on the cure for HIV infection. In recent years, some intriguing and inspiring cases indicated that the cure of HIV infection （HIV cure） or durable alleviation of HIV infection may not be a dream any more. ＇Berlin Patient＇＇Mississippi Baby＇, and probably ＇Long Beach Baby＇ have brought great hope to the HIV cure. Many scientists believe that the HIV cure is just a question of time.

关键词： HIV Cure and HIV Reservoirs ZFN

Influences of petroleum on accumulation of copper and cadmium in the polychaete Nereis diversicolor

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Journal of Environmental Sciences 2006年第1期18卷 109-114页

作者： SUN Fu-hong ZHOU Qi-xing ZHANG qian-ru Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China College of Environmental Sciences and Engineering Nankai University Tianjin 300071 China

Using the exposure simulation experiment, the action of petroleum affecting the accumulation of the trace metals including copper （Cu） and cadmium （Cd） in littoral polychaete Nereis diversicolor collected from the Shuangtaizi Estuary in Liaoning Province, China was examined. The results showed that there was a markedly non-linear relationship between the accumulation of Cu in worms and the experimental concentration of Cu in exposure solutions when the concentration of petroleum remained at 0, 100, and 220 μl/L, respectively. However, significantly non-linear relationship for worms exposed to Cd was observed only when the concentration of added petroleum was 0 and 220 μl/L. The accumulation of Cu in worms did not differ significantly among the three different levels of petroleum concentrations combined with various concentrations of Cu. So was the accumulation of Cd in worms （p〉0.05）. However, the addition of petroleum in exposure solutions brought about an increase in the accumulation of Cu in Nereis diversicolor, in comparison with single Cu pollution. On the other hand, when the concentration of added petroleum remained at 100 μl/L, the accumulation of Cd in worms was lower than that in worms exposed to various concentrations of only cadmium. However, the worms exposed to Cd and petroleum 220 μl/L did not show obvious and identical increase in the accumulation of Cd, compared with single Cd exposure. The accumulation of both Cu and Cd in worms did not increase significantly with the increases in concentrations of Cu or Cd in exposure solutions combined with petroleum （0, 100, and 220μl/L） under the experimental conditions. Although Nereis diversicolor is exposed to very high Cu and Cd in exposure solutions, accumulation and detoxification mechanisms are sufficient to cope with the extra metal influx in order to survive.

关键词： Nereis diversicolor copper cadmium petroleum combined pollution

Theoretical studies on alloying of germanene supported on Al (111) substrate

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Chinese Physics B 2020年第10期29卷 521-534页

作者： qian-xing Chen Hao Yang Gang Chen Laboratory of Advanced Materials Physics and Nanodevices School of Physics and TechnologyUniversity of JinanJinan 250022China School of Physics and Electronics Shandong Normal UniversityJinan 250358China

Using density functional theory,we study the alloying of the buckled hexagonal germanene superlattice supported on Al(111)-(3×3),the sheet composed of triangular,rhombic,and pentagonal motifs on Al(111)-(3×3),and the buckled geometry on Al(111)-(√7×√7)(19°),which are denoted,respectively,by BHS,TRP,and SRT7,to facilitate the discussion in this *** could be alloyed in the low doping concentration *** stable configurations BHS,TRP,and SRT7 of the pure and alloyed germanenes supported on both Al(111) and its Al2 Ge surface alloy,except the SRT7 pure germanene on Al2 Ge,could re-produce the experimental scanning tunneling microscopy *** relatively stable AlGe alloy species are the Al3 Ge5 BHS-2 T,Al3 Ge5 TRP-2 T,and Al3 Ge3 SRT7-1 T on Al(111) while they are the Al4 Ge4 BHS-1 T,Al3 Ge5 TRP-2 T,and A127 Ge27 SRT7-(3×3)-9 T on Al2 Ge(the n in the nT means that there are n Ge atoms per unit which sit at the top sites and protrude upward).In addition,the Al3 Ge5 BHS-2 T and Al4 Ge4 BHS-1 T are the most stable alloy sheets on Al(111) and Al2 Ge,*** with the experimental studies,there exists no structural transition among these alloyed configurations,which suggests that the experimental conditions play a crucial role in selectively growing the pure or the alloyed germanene sheets,which may also help grow the one-atomic thick honeycomb structure on idea Al(111).

关键词： first-principles calculation alloyed two-dimensional material substrate for two-dimensional material growth two-dimensional nanostructure

Introduction to the Special Issue on Modeling and Simulation of Fluid Flows in Fractured PorousMedia:Current Trends and Prospects

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Computer Modeling in Engineering & Sciences 2021年第2期126卷 437-441页

作者： qian yin Yujing Jiang Richeng Liu State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221116China Key Laboratory of Mining Disaster Prevention and Control Shandong University of Science and TechnologyQingdao266590China School of Engineering Nagasaki UniversityNagasaki8528521Japan

Understanding the fluid flow mechanisms in fractured porous media plays an important role in many engineering activities,such as nuclear waste disposal,geothermal energy extraction,oil and natural gas production,as well as performance and safety of underground projects including coal mines and *** recent years,many methods including numerical simulation,laboratory experiment and theoretical analysis have been employed to investigate the flowing process and permeability response of rock mass and rock fractures,from kilometer scale to ***,the rocks/coals are in deep underground that is very complex and exists some uncertainties.

关键词： underground rock flowing

Nonadiabatic dynamics and geometric phase of an ultrafast rotating electron spin

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Science Bulletin 2019年第6期64卷 380-384页

作者： xing-Yan Chen Tongcang Li Zhang-Qi yin Center for Quantum Information Institute for Interdisciplinary Information Sciences Tsinghua University Max-Planck-Institut für Quantenoptik Fakult?t für Physik Ludwig-Maximilians-Universit?t München Department of Physics and Astronomy Purdue University School of Electrical and Computer Engineering Purdue University Purdue Quantum Center Purdue University Birck Nanotechnology Center Purdue University

The spin in a rotating frame has attracted a lot of attentions recently,as it deeply relates to both fundamental physics such as pseudo-magnetic field and geometric phase,and applications such as gyroscopic ***,previous studies only focused on adiabatic limit,where the rotating frequency is much smaller than the spin *** we propose to use a levitated nano-diamond with a built-in nitrogen-vacancy(NV)center to study the dynamics and the geometric phase of a rotating electron spin without adiabatic *** find that the transition between the spin levels appears when the rotating frequency is comparable to the spin frequency at zero magnetic *** we use Floquet theory to numerically solve the spin energy spectrum,study the spin dynamics and calculate the geometric phase under a finite magnetic field,where the rotating frequency to induce resonant transition could be greatly reduced.

关键词： Nitrogen-vacancy center Nonadiabatic geometric phase Ultrafast rotor Rabi oscillation Optomechanics

Effects of the original state of sodium-based additives on microstructure,surface characteristics and filtration performance of SiC membranes

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Chinese Journal of Chemical Engineering 2023年第11期63卷 1-11页

作者： Yuling Xie Qilin Gu qian Jiang Zhaoxiang Zhong Weihong xing National Engineering Research Center for Special Separation Membrane State Key Laboratory of Materials-Oriented Chemical EngineeringCollege of Chemical EngineeringNanjing Tech UniversityNanjing 210009China School of Environmental Science and Engineering Nanjing Tech UniversityNanjing 211816China

Sodium-contained compounds are promising sintering additives for the low-temperature preparation of reaction bonded SiC *** sodium-based sintering additives in various original states were attempted,their effects on microstructure and surface properties have rarely been *** this work,three types of sodium-based additives,including solid-state NaA zeolite residue(NaA)and liquidstate dodecylbenzene sulfonate(SDBS)and water glass(WG),were separately adopted to prepare SiC membranes,and the microstructure,surface characteristics and filtration performance of these SiC membranes were comparatively *** showed that the SiC membranes prepared with liquid-state SDBS and WG(S-SDBS and S-WG)showed lower open porosity yet higher bending strength compared to those prepared with solid-state NaA(S-NaA).The observed differences in bending strength were further interpreted by analyzing the reaction process of each sintering additive and the composition of the bonding phase in the reaction bonded SiC ***,the microstructural differentiation was correlated to the original state of the *** addition,their surface characteristics and filtration performance for oil-in-water emulsion were examined and correlated to the membrane *** S-NaA samples showed higher hydrophilicity,lower surface roughness(1.80μm)and higher rejection ratio(99.99%)in O/W emulsion separation than those of S-WG and *** can be attributed to the smaller mean pore size and higher open porosity,resulting from the originally solid-state NaA ***,this work revealed the comprehensive effects of original state of sintering additives on the prepared SiC membranes,which could be helpful for the application-oriented fabrication by choosing additives in suitable state.

关键词： SiC membrane Sintering additive Reaction sintering Microstructure Oil-in-water emulsions