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Oilfield analogy and productivity prediction based on machine learning: Field cases in PL oilfield, china

Petroleum Science 2024年第4期21卷 2554-2570页

作者： Wen-Peng Bai Shi-Qing Cheng Xin-Yang guo Yang Wang Qiao guo Chao-Dong Tan State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing)

In the early time of oilfield development, insufficient production data and unclear understanding of oil production presented a challenge to reservoir engineers in devising effective development plans. To address this challenge, this study proposes a method using data mining technology to search for similar oil fields and predict well productivity. A query system of 135 analogy parameters is established based on geological and reservoir engineering research, and the weight values of these parameters are calculated using a data algorithm to establish an analogy system. The fuzzy matter-element algorithm is then used to calculate the similarity between oil fields, with fields having similarity greater than 70% identified as similar oil fields. Using similar oil fields as sample data, 8 important factors affecting well productivity are identified using the Pearson coefficient and mean decrease impurity（MDI） method. To establish productivity prediction models, linear regression（LR）, random forest regression（RF）, support vector regression（SVR）, backpropagation（BP）, extreme gradient boosting（XGBoost）, and light gradient boosting machine（Light GBM） algorithms are used. Their performance is evaluated using the coefficient of determination（R2）, explained variance score（EV）, mean squared error（MSE）, and mean absolute error（MAE） metrics. The Light GBM model is selected to predict the productivity of 30 wells in the PL field with an average error of only 6.31%, which significantly improves the accuracy of the productivity prediction and meets the application requirements in the field. Finally, a software platform integrating data query,oil field analogy, productivity prediction, and knowledge base is established to identify patterns in massive reservoir development data and provide valuable technical references for new reservoir development.

关键词： Data mining technique Analogy parameters Oilfield analogy Productivity prediction Software platform

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Differentially private SGD with random features

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Applied mathematics(A Journal of Chinese Universities) 2024年第1期39卷 1-23页

作者： WANG Yi-guang guo Zheng-chu Polytechnic Institute of Zhejiang university Zhejiang UniversityHangzhou 310015China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China

In the realm of large-scale machine learning,it is crucial to explore methods for reducing computational complexity and memory demands while maintaining generalization ***,since the collected data may contain some sensitive information,it is also of great significance to study privacy-preserving machine learning *** paper focuses on the performance of the differentially private stochastic gradient descent(SGD)algorithm based on random *** begin,the algorithm maps the original data into a lowdimensional space,thereby avoiding the traditional kernel method for large-scale data storage ***,the algorithm iteratively optimizes parameters using the stochastic gradient descent ***,the output perturbation mechanism is employed to introduce random noise,ensuring algorithmic *** prove that the proposed algorithm satisfies the differential privacy while achieving fast convergence rates under some mild conditions.

关键词： learning theory differential privacy stochastic gradient descent random features reproducing kernel Hilbert spaces

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Existence and Uniqueness of Stationary Solutions of Non-Newtonian Viscous Incompressible Fluids

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Communications in Nonlinear Science and Numerical Simulation 1999年第1期4卷 63-68页

作者： Boling guo* and guoguang LIN**,+ (Institute of Applied Physics and Computational mathematics, Beijing 100088, china) guoguang LIN (Graduate School of china Academy of Engineering Physics, Beijing 100088, china) + (Department of mathematics, yunnan Unive Inst. Appl. Phys. and Compl. Math. Beijing 100088 China Graduate School China Academy of Engineering Physics Beijing 100088 China Department of mathematics Yunnan University Kunming 650091 China

The existence and uniqueness of stationary solution a bipolar incompressible viscous fluids is *** is also obtained that the every solution of the system converges to the stationary solution as time t → ∞.

关键词： non-Newtonian fluid stationary solution, asymptotic behavior bipolar fluid

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Density functional theory study of B- and Si-doped carbons and their adsorption interactions with sulfur compounds

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Carbon Energy 2024年第2期6卷 195-208页

作者： Peng guo Hong Zhang Shuliang Dong Libao An College of Mechanical Engineering North China University of Science and TechnologyTangshanHebeiChina College of Life Sciences North China University of Science and TechnologyTangshanHebeiChina

Understanding the adsorption interactions between carbon materials and sulfur compounds has far-reaching impacts,in addition to their well-known important role in energy storage and conversion,such as lithium-ion *** this paper,properties of intrinsic B or Si single-atom doped,and B-Si codoped graphene(GR)and graphdiyne(GDY)were investigated by using density functional theory-based calculations,in which the optimal doping configurations were explored for potential applications in adsorbing sulfur *** showed that both B or Si single-atom doping and B-Si codoping could substantially enhance the electron transport properties of GR and GDY,improving their surface ***,B and Si atoms displayed synergistic effects for the codoped configurations,where B-Si codoped GR/GDY exhibited much better performance in the adsorption of sulfurcontaining chemicals than single-atom doped *** addition,results demonstrated that,after B-Si codoping,the adsorption energy and charge transfer amounts of GDY with sulfur compounds were much larger than those of GR,indicating that B-Si codoped GDY might be a favorable material for more effectively interacting with sulfur reagents.

关键词： adsorption density functional theory doping graphdiyne graphene sulfur compounds

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Presentation of the Berry-Tabor conjecture in Levy plates

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Chinese Physics B 2024年第10期33卷 240-247页

作者： Chao Li guo-Lin Hou School of Mathematical Sciences Inner Mongolia UniversityHohhot 010021China

The Berry-Tabor(BT)conjecture is a famous statistical inference in quantum chaos,which not only establishes the spectral fluctuations of quantum systems whose classical counterparts are integrable but can also be used to describe other wave *** this paper,the BT conjecture has been extended to Lévy *** predicted by the BT conjecture,level clustering is present in the spectra of Lévy *** consequence of level clustering is studied by introducing the distribution of nearest neighbor frequency level spacing ratios P(r),which is calculated through the analytical solution obtained by the Hamiltonian *** work investigates the impact of varying foundation parameters,rotary inertia,and boundary conditions on the frequency spectra,and we find that P(r)conforms to a Poisson distribution in all *** reason for the occurrence of the Poisson distribution in the Lévy plates is the independence between modal frequencies,which can be understood through mode functions.

关键词： Berry-Tabor conjecture frequency spectra Hamiltonian approach Lévy plates

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Impact of Alcian blue and periodic acid Schiff expression on the prognosis of gastric signet ring cell carcinoma

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 687-698页

作者： Juan Lin Zhu-Feng Chen guo-Dong guo Xin Chen Shengli Clinical Medical College Fujian Medical UniversityFuzhou 350001Fujian ProvinceChina Department of Pathology Fujian Provincial HospitalFuzhou 350001Fujian ProvinceChina Department of Internal Medicine Fujian Provincial HospitalFuzhou 350001Fujian ProvinceChina

BACKGROUND The Alcian blue(AB)and periodic acid Schiff(PAS)stains are representative mucus markers in gastric signet ring cell carcinoma(SRCC).They are low-cost special staining methods used to detect acidic mucus and neutral mucus,***,the clinical importance of the special combined AB and PAS stain is *** To investigate AB expression,PAS expression and the AB-to-PAS(A/P)ratio in gastric SRCC patients and to assess patient *** Paraffin-embedded sections from 83 patients with gastric SRCC were stained with AB and PAS,and signet ring cell positivity was assessed ***-histochemical staining for Ki67,protein 53(P53)and human epidermal growth factor receptor 2(HER2)was performed *** cancer-specific survival(CSS)rate was estimated via Kaplan-Meier *** proportional hazards models were used for univariate and multivariate survival *** Kaplan-Meier survival analysis revealed that the 3-year CSS rate was significantly greater in the high-PAS-expression subgroup than in the low-PAS-expression subgroup(P0.5 group(P=0.042).Univariate Cox regression analysis revealed that the factors affecting prognosis included tumor diameter,lymph node metastasis,vessel carcinoma embolus,tumor stage,the A/P ratio and the expression of Ki67,P53 and the *** multivariate regression analysis confirmed that low PAS expression[hazard ratio(HR)=3.809,95%confidence interval(CI):1.563-9.283,P=0.003]and large tumor diameter(HR=2.761,95%CI:1.086-7.020,P=0.033)were independent risk factors for poor *** A/P>0.5 is potentially a risk factor for prognosis,and low PAS expression is an independent risk factor in the prognosis of gastric *** expression and the A/P ratio could help in predicting the clinical prognosis of patients with SRCC.

关键词： Alcian blue Periodic acid-Schiff Prognosis Gastric Signet ring cell carcinoma

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Electronic structure engineering of transition metal dichalcogenides for boosting hydrogen energy conversion electrocatalysts

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Chinese Physics B 2024年第9期33卷 13-28页

作者： Bing Hao Jingjing guo Peizhi Liu Junjie guo Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China

Electrocatalytic water splitting for hydrogen production is an appealing strategy to reduce carbon emissions and generate renewable *** promising process,however,is limited by its sluggish reaction kinetics and high-cost *** two-dimensional(2D)transition metal dichalcogenides(TMDCs)have presented great potential as electrocatalytic materials due to their tunable bandgaps,abundant defective active sites,and good chemical ***,phase engineering,defect engineering and interface engineering have been adopted to manipulate the electronic structure of TMDCs for boosting their exceptional catalytic ***,it is essential to clarify the local structure of catalytically active sites of TMDCs and their structural evolution in catalytic reactions using atomic resolution electron microscopy and the booming in situ technologies,which is beneficial for exploring the underlying reaction *** this review,the growth regulation,characterization,particularly atomic configurations of active sites in TMDCs are *** significant role of electron microscopy in the understanding of the growth mechanism,the controlled synthesis and functional optimization of 2D TMDCs are *** review will shed light on the design and synthesis of novel electrocatalysts with high performance,as well as prompt the application of advanced electron microscopy in the research of materials science.

关键词： TMDCs STEM hydrogen energy conversion active site identification

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Deep genome skimming reveals the hybrid origin of Pseudosasa gracilis (Poaceae: Bambusoideae)

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Plant Diversity 2024年第3期46卷 344-352页

作者： Xiang-Zhou Hu Cen guo Sheng-Yuan Qin De-Zhu Li Zhen-Hua guo Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China university of Chinese Academy of Sciences Beijing 100049China

Pseudosasa gracilis(Poaceae:Bambusoideae)is a temperate woody bamboo species endemic to Southcentral china with a narrow *** phylogenetic studies revealed an unexpected,isolated phylogenetic position of *** we conducted phylogenomic analysis by sampling populations of *** and its sympatric species *** and Sinosasa polytricha reflecting different genomic signals,by deep genome *** molecular evidence from chloroplast genes and genome-wide SNPs,we deciphered the phylogenetic relationships of *** plastid and nuclear data indicate that *** is more closely related to Sinosasa,which is discordant with the taxonomic *** further explore this molecular-morphological conflict,we screened 411“perfect-copy”syntenic genes to reconstruct phylogenies using both the concatenation and coalescent *** observed extensive discordance between gene trees and the putative species tree.A significant hybridization event was detected based on 411 genes from the D subgenome,showing *** was a hybrid descendant between Sinosasa longiligulata and ***,with 63.56%and 36.44%inheritance probabilities of each ***,introgression events were detected in the C subgenome between *** and *** in the same distribution *** findings suggest that sympatric hybridization and introgression play a crucial role in the origin of *** providing an empirical example of bamboo of hybrid origin using comprehensive analyses based on genomic data from different inheritance systems and morphological characters,our study represents a step forward in understanding of reticulate evolution of bamboos.

关键词： Phylogenomics Hybridization Introgression Pseudosasa gracilis Pseudosasa Sinosasa

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Fullerenes and derivatives as electrocatalysts: Promises and challenges

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Green Energy & Environment 2024年第1期9卷 7-27页

作者： Kun guo Ning Li Lipiao Bao Xing Lu State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

Carbon-based metal-free nanomaterials are promising alternatives to precious metals as electrocatalysts of key energy storage and conversion *** paramount signiﬁcance are the establishment of design principles by understanding the catalytic mechanisms and identifying the active *** from sp2-conjugated graphene and carbon nanotube,fullerene possesses unique characteristics that are growingly being discovered and exploited by the electrocatalysis *** instance,the well-deﬁned atomic and molecular structures,the good electron afﬁnity to tune the electronic structures of other substances,the intermolecular self-assembly into superlattices,and the on-demand chemical modiﬁcation have endowed fullerene with incomparable advantages as electrocatalysts that are otherwise not applicable to other carbon *** increasing studies are being reported on this intriguing topic,it is necessary to provide a state-of-the-art overview of the recent *** review takes such an initiative by summarizing the promises and challenges in the electrocatalytic applications of fullerene and its *** content is structured according to the composition and structure of fullerene,including intact fullerene(e.g.,fullerene composite and superlattices)and fullerene derivatives(e.g.,doped,endohedral,and disintegrated fullerene).The synthesis,characterization,catalytic mechanisms,and deﬁciencies of these fullerene-based materials are explicitly *** conclude it by sharing our perspectives on the key aspects that future efforts shall consider.

关键词： Fullerene Fullerene derivative Metal-free catalyst Structural defect Electrocatalyst

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Fluid-structure interaction simulation for multi-body flexible morphing structures

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Chinese Journal of Aeronautics 2024年第2期37卷 137-147页

作者： Wenzhi guo Yongtao SHUI Lu NIE Gang CHEN State Key Laboratory of Strength and Vibration for Mechanic Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China china Academy of Launch Vehicle Technology Beijing 100076China china Academy of Aerospace Science and Innovation Beijing 100086China Shannxi Key Laboratory of Service Environment and Control for Flight Vehicles Xi’an Jiaotong UniversityXi’an 710049China

The multi-body flexible morphing airfoil can improve the aerodynamic characteristics based on different flight missions *** researches have focused on the unsteady aerodynamic characteristics of flexible wings under passive ***,the unsteady aerodynamic characteristics with the fluid-structure interaction effects in the multi-body active actuation process of morphing airfoil deserve further *** this paper,a fluid-structure coupled simulation method for multi-body flexible morphing airfoil with active actuation subsystem was investigated,and the aerodynamic characteristics during deformation were compared with different skin flexibility,flow field environment,actuation mode and actuation *** numerical results show that for the steady aerodynamic,the skin flexibility can improve the stability *** the unsteady process,the change trend of the transient lift coefficient and pitching moment are consistent with those of the active drive characteristics,while the instantaneous lift-drag ratio coefficient is greatly affected by the driving mode and can be improved by increasing the driving duration.

关键词： Fluid-structure interaction Multi-body dynamics modeling Flexible structures Aerodynamics Morphing wings

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