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Lithological Facies Classification Using Attention-Based Gated Recurrent Unit

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Tsinghua science and Technology 2024年第4期29卷 1206-1218页

作者： Yuwen Liu Yulan Zhang Xingyuan Mao Xucheng Zhou Jingwen Chang Wenwei Wang Pan Wang Lianyong Qi College of Computer science and Technology China University of Petroleum(East China)Qingdao 266580China Shandong Provincial University Laboratory for Protected Horticulture Weifang University of Science and TechnologyShouguang 262700China School of Mechanical Electrical and Information EngineeringShandong UniversityWeihai 264209China Shandong Provincial Key Laboratory of Network Based Intelligent Computing University of JinanJinan 250022China School of Modern Posts Nanjing University of Posts and TelecommunicationsNanjing 210023China

Lithological facies classification is a pivotal task in petroleum geology, underpinning reservoir characterization and influencing decision-making in exploration and production operations. Traditional classification methods, such as support vector machines and Gaussian process classifiers, often struggle with the complexity and nonlinearity of geological data, leading to suboptimal performance. Moreover, numerous prevalent approaches fail to adequately consider the inherent dependencies in the sequence of measurements from adjacent depths in a well. A novel approach leveraging an attention-based gated recurrent unit (AGRU) model is introduced in this paper to address these challenges. The AGRU model excels by exploiting the sequential nature of well-log data and capturing long-range dependencies through an attention mechanism. This model enables a flexible and context-dependent weighting of different parts of the sequence, enhancing the discernment of key features for classification. The proposed method was validated on two publicly available datasets. Results demonstrate a considerably improvement over traditional methods. Specifically, the AGRU model achieved superior performance metrics considering precision, recall, and F1-score.

关键词： attention mechanism facies classification GRU MLP(multilayer perceptron)

Possible bias of the constraints on the Hubble constant owing to the quasi-Gaussian distribution of DM_(IGM)in fast radio bursts

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Chinese Physics C 2024年第7期48卷 211-220页

作者：陈贵垚李昕 Department of Physics Chongqing UniversityChongqing 401331China Chongqing Key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China

Fast radio bursts(FRBs)are useful cosmological probes with numerous applications in *** distribution of the dispersion measurement contribution from the intergalactic medium is a key issue.A quasi-Gaussian distribution has been used to replace the traditional Gaussian distribution,yielding promising ***,this study suggests that there may be additional challenges in its *** used 35 well-localized FRBs to constrain the Hubble constant H_(0)along with two FRB-related parameters,yielding H_(0)=■The best-fitting Hubble constant H_(0)is smaller than the value obtained from the Cosmic Microwave Background(CMB),which may be caused by the small sample size of current FRB *** Carlo simulations indicate that a set of 100 simulated FRBs provides a more precise fitting result for the Hubble ***,the precision of the Hubble constant does not improve when further enlarging the FRB *** simulations reveal a systematic deviation in the fitting results of H_(0),attributed to the quasi-Gaussian distribution of the dispersion measure in the intergalactic *** this,the results remain reliable within 1σuncertainty,assuming that a sufficient number of FRB data points are available.

关键词： fast radio bursts Hubble constant cosmological parameters

Three-dimensional structural models,evolution and petroleum geological significances of transtensional faults in the Ziyang area,central Sichuan Basin,SW china

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Petroleum Exploration and Development 2024年第3期51卷 604-620页

作者： TIAN Fanglei GUO Tonglou HE Dengfa GU Zhanyu MENG Xianwu WANG Renfu WANG Ying ZHANG Weikang LU Guo School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Enrichment Mechanism Ministry of EducationBeijing 100083China Sinopec Southwest Oil and Gas Company Chengdu 610031China

With drilling and seismic data of Transtensional(strike-slip)Fault System in the Ziyang area of the central Sichuan Basin,SW china plane-section integrated structural interpretation,3-D fault framework model building,fault throw analyzing,and balanced profile restoration,it is pointed out that the transtensional fault system in the Ziyang 3-D seismic survey consists of the northeast-trending F_(I)19 and F_(I)20 fault zones dominated by extensional deformation,as well as 3 sets of northwest-trending en echelon normal faults experienced dextral shear *** them,the F_(I)19 and F_(I)20 fault zones cut through the Neoproterozoic to Lower Triassic Jialingjiang Formation,presenting a 3-D structure of an“S”-shaped *** before Permian and during the Early Triassic,the F_(I)19 and F_(I)20 fault zones underwent at least two periods of structural ***,the 3 sets of northwest-trending en echelon normal faults are composed of small normal faults arranged in pairs,with opposite dip directions and partially left-stepped *** before Permian,they had formed almost,restricting the eastward growth and propagation of the F_(I)19 fault *** F_(I)19 and F_(I)20 fault zones communicate multiple sets of source rocks and reservoirs from deep to shallow,and the timing of fault activity matches well with oil and gas generation *** there were favorable Cambrian-Triassic sedimentary facies and reservoirs developing on the local anticlinal belts of both sides of the F_(I)19 and F_(I)20 fault zones,the major reservoirs in this area are expected to achieve breakthroughs in oil and gas exploration.

关键词： transtensional(strike-slip)fault three-dimensional structural model structural evolution petroleum geological significance Ziyang area Sichuan Basin

Synthesis and optical properties of highly efficient Na_(3)KMg_(7)(PO_(4))_(6):Eu^(2+)blue phosphor for full-spectrum white-light-emitting diodes:The role of Li_(2)CO_(3)flux

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Journal of Rare Earths 2024年第7期42卷 1217-1223,I0001页

作者： Zihao Wang Sisi Liang Chenyang Zhan Kunyuan Xu Jie Hu Dejian Chen Liping Song Haomiao Zhu School of Physics and Materials science Nanchang UniversityNanchang330000China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341000China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Research Center of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen361021China

Full-spectrum phosphor-converted white-light-emitting diodes(pc-WLED)are emerging as a mainstream technology in semiconductor ***,high-performance blue phosphor which can be excited efficiently by a 400 nm NUV diode chip is still ***,we present a blue-emitting Na_(3)KMg_(7)(PO_(4))6:Eu^(2+)phosphor synthesized by the solid-reaction ***,we find that the using of Li_(2)CO_(3)as flux can significantly improve the crystal quality and thus the emission efficiency of the ***,the excitation peak of the phosphor shifts from 365 to 400 nm,which is pivotal for efficient NUV(400 nm)diode chip *** practical Eu^(2+)concentration is also enhanced by using Li_(2)CO_(3)as flux,and the absorption efficiency is greatly *** phosphor exhibits superior PL thermal stability,namely retains 94%integrated photoluminescence intensity at 150℃of that at 25℃.As a result,the optimized phosphor shows an emission band peaked at 437 nm with a bandwidth of 40 nm and a high external photoluminescence quantum yield of 51.7%.Finally,a pc-WLED was fabricated by using NKMPO:Eu^(2+)blue,Sr_(2)SiO_(4):Eu^(2+)green,CaAlSiN_(3):Eu^(2+)red phosphors,and a 400 nm NUV diode *** shows a high color rendering index of R_(a)=96.4 and a correlated color temperature of 4358 *** results prove that NKMPO:Eu^(2+)is a promising blue phosphor for full-spectrum WLED based on NUV diode chips.

关键词： Eu^(2+) Blue phosphor Na_(3)KMg_(7)(PO_(4))_(6) Full-spectrum white LEDs Rare earths

Evolution of copper species during heat treatment and its effect on CO oxidation reaction on CuCeZrO_(y) catalyst synthesized by a facile solvent-free route

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Journal of Rare Earths 2024年第4期42卷 660-667页

作者： Guangying Fu Dongsen Mao Jun Yu Qiangsheng Guo School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai21418 China The ZeoMat Group Qingdao Institute of Bioenergy and Bioprocess TechnologyCASQingdao26611China

Several ternary oxides CuCeZrO_(y)(CCZ)were synthesized by a facile grinding method followed by calcination at high temperatures,and used as catalysts for CO oxidation at low *** influences of calcination temperature(400-600℃)on the physicochemical properties of the assynthesized ternary oxides were investigated by thermogravimetric analysis/differential scanning calorimetry(TGA/DSC),X-ray diffraction(XRD),transmission electron microscopy(TEM),Raman,inductively coupled plasma-optical emission spectrometry(ICP-OES),N_(2) adsorption,H_(2)-temperature programmed reduction(H_(2)-TPR),and X-ray photoelectron spectroscopy(XPS)*** results show that the increase in calcination temperature from 400 to 500℃is conducive to the high dispersion of CuOx on catalyst surface and the incorporation of Cu species into the support to form the Cu-Ce-Zr-O solid *** raising of calcination temperature from 500 to 600℃,however,leads to the segregation of Cu species from the solid solution to aggregate on support surface and growth of highly dispersed CuOx *** highest catalytic activity is acquired over the CCZ calcined at 500℃,which can be ascribed to the largest contents of Cu+species and oxygen vacancies owing to the formation of the maximum amount of Cu-Ce-Zr-O solid solution.

关键词： CuCeZrO_(y)catalyst co oxidation Calcination temperature Grinding method Oxalate precursor Rare earths

Efficient and selective recovery of Gd(Ⅲ)via polyethyleneimine modification of lanthanum-based metal-organic frameworks

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Journal of Rare Earths 2024年第1期42卷 210-219,I0007页

作者： Wenhao Li Lijinhong Huang Bin Xiao Xiaoguang Duan Haike Li Lang Li Wanfu Huang Ganzhou Key Laboratory of Basin Pollution Simulation and Control Jiangxi University of Science and TechnologyGanzhou341000China Innovation Center for Water Quality Security Technology at Ganjiang River Basin Jiangxi University of Science and TechnologyGanzhou341000China Faculty of science and Engineering WA School of Mines:MineralsEnergy and Chemical EngineeringCurtin UniversityWAAustralia School of Architecture and Design Jiangxi University of Science and TechnologyGanzhou341000China School of Resources and Architectural Engineering Gannan University of Science and TechnologyGanzhou341000China School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaideSA5005Australia School of Resource and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou341000China

With the development of the economy and the increasing demand for environmental protection,the efficient and selective recovery of Gd(Ⅲ)from actual wastewater is of critical *** this work,lanthanum-based metal-organic framework(LaBDC)materials were prepared by a hydrothermal method,and then polyethyleneimine(PEI)and LaBDC were combined by an impregnation method to form a novel LaBDC@xPEI *** prepared materials were characterized using Fourier transfo rm infrared spectroscopy(FTIR),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDX),B runauer-Emmett-Teller(BET),thermogravimetric analysis(TGA)and X-ray photoelectron spectroscopy(XPS).Experiments show that LaBDC@50%PEI has the highest adsorption capacity(181.77 mg/g)among lanthanum-based MOFs with different PEI loadings at pH=5.5,which is about 5.1 times that of bare *** adsorption isotherm analysis shows that LaBDC@50%PEI follows the Langmuir *** addition,the adsorption kinetics of LaBDC@50%PEI follows a pseudo-second-order kinetic model,indicating that the adsorption process is chemical *** is worth noting that LaBDC@50%PEI maintains good adsorption performance and stability after three recycling tests,and exhibits excellent selectivity in cation interference ***,the LaBDC@50%PEI composites possess good stability and hold great promises in rapid recovery of Gd(Ⅲ)from practical aqueous environments.

关键词： Wet-impregnation method Polyethylene imine Metaleorganic frameworks Lanthanum Recovery of Gd(Ⅲ) Rare earths

An air combat maneuver pattern extraction based on time series segmentation and clustering analysis

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Defence Technology（防务技术） 2024年第6期36卷 149-162页

作者： Zhifei Xi Yingxin Kou Zhanwu Li Yue Lv You Li Air Force Engineering University No.1 Baling RoadBaqiao DistrictXi'anShaanxi ProvinceChina

Target maneuver recognition is a prerequisite for air combat situation awareness,trajectory prediction,threat assessment and maneuver *** get rid of the dependence of the current target maneuver recognition method on empirical criteria and sample data,and automatically and adaptively complete the task of extracting the target maneuver pattern,in this paper,an air combat maneuver pattern extraction based on time series segmentation and clustering analysis is proposed by combining autoencoder,G-G clustering algorithm and the selective ensemble clustering analysis ***,the autoencoder is used to extract key features of maneuvering trajectory to remove the impacts of redundant variables and reduce the data dimension;Then,taking the time information into account,the segmentation of Maneuver characteristic time series is realized with the improved FSTS-AEGG algorithm,and a large number of maneuver primitives are extracted;Finally,the maneuver primitives are grouped into some categories by using the selective ensemble multiple time series clustering algorithm,which can prove that each class represents a maneuver *** maneuver pattern extraction method is applied to small scale air combat trajectory and can recognize and correctly partition at least 71.3%of maneuver actions,indicating that the method is effective and satisfies the requirements for engineering *** addition,this method can provide data support for various target maneuvering recognition methods proposed in the literature,greatly reduce the workload and improve the recognition accuracy.

关键词： Maneuver pattern extraction Data mining Fuzzy segmentation Selective ensemble clustering

A phase-field model for simulating the propagation behavior of mixed-mode cracks during the hydraulic fracturing process in fractured reservoirs

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 911-930页

作者： Dan ZHANG Liangping YI Zhaozhong YANG Jingqiang ZHANG Gang CHEN Ruoyu YANG Xiaogang LI State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Tarim Oilfield Company PetroChinaBayingolin Mongolian Autonomous Prefecture 841000Xinjiang Uygur Autonomous RegionChina Wuqi Oil Production Plant Shaanxi Yanchang PetroleumXi'an 716000China Exploration Division of Petrochina Southwest Oil and Gasfield Company Chengdu 610041China

A novel phase-field model for the propagation of mixed-mode hydraulic fractures,characterized by the formation of mixed-mode fractures due to the interactions between fluids and solids,is *** this model,the driving force for the phase field consists of both tensile and shear components,with the fluid contribution primarily manifesting in the tension driving *** displacement and pressure are solved simultaneously by an implicit *** numerical solution's iterative format is established by the finite element discretization and Newton-Raphson(NR)iterative *** correctness of the model is verified through the uniaxial compression physical experiments on fluid-pressurized rocks,and the limitations of the hydraulic fracture expansion phase-field model,which only considers mode I fractures,are *** addition,the influence of matrix mode II fracture toughness value,natural fracture mode II toughness value,and fracturing fluid injection rate on the hydraulic fracture propagation in porous media with natural fractures is studied.

关键词： mixed-mode crack hydraulic fracturing poro-elasticity phase-field method(PFM)

Research on modeling and self-excited vibration mechanism in magnetic levitation-collision interface coupling system

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 873-890页

作者： Jinghu TANG Chaofeng LI Jin ZHOU Zhiwei WU School of Mechanical Engineering&Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems of Ministry of Education of china Northeastern UniversityShenyang 110819China School of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The modeling and self-excited vibration mechanism in the magnetic levitation-collision interface coupling system are *** effects of the control and interface parameters on the system's stability are *** frequency range of self-excited vibrations is investigated from the energy point of *** phenomenon of self-excited vibrations is elaborated with the phase *** corresponding control strategies are briefly analyzed with respect to the vibration *** results show that when the levitation objects collide with the mechanical interface,the system's vibration frequency becomes larger with the decrease in the collision gap;when the vibration frequency exceeds the critical frequency,the electromagnetic system continues to provide energy to the system,and the collision interface continuously dissipates energy so that the system enters the self-excited vibration state.

关键词： magnetic levitation coupling system self-excited vibration mechanical interface vibration frequency